Report on Human Biomonitoring of Environmental Chemicals in Canada

8. Results by Chemical Group

Contents

8.1 Metals and Trace Elements

8.1.1 Antimony (CASRN 7440-36-0)

Antimony (Sb) is a naturally occurring element that comprises a small fraction of the Earth's crust. It is classified as a metalloid, exhibiting both metallic and non-metallic characteristics. It can exist as an uncombined metal as well as in various oxidation states (-3, 0, +3, +5) and forms (ATSDR, 1992).

Antimony is released into the environment primarily through industrial processes. It may enter the aquatic environment by way of effluents from mining and manufacturing operations, as well as through industrial and municipal leachate discharges, and it is released into the air as stack dust from industrial sources, such as coal-fired power plants, inorganic chemical plants, and metal smelters (Health Canada, 1997). However, it is also found in the environment naturally due to natural weathering of rocks, runoff from soils, emissions from volcanic eruptions, sea spray, and forest fires. Antimony can be obtained from mining or produced from smelting and refining of scrap metals (ATSDR, 1992; Health Canada, 1997). Antimony is used in the production of semi-conductors, infrared detectors, and diodes; as a component in alloys for batteries, cable sheathing, plumbing solder, ammunition and fireworks, flame retardant and anti-friction materials; and as an additive in paint pigments, glass, and ceramic products (Health Canada, 1997; NTP, 2005; ATSDR, 1992). Some forms of antimony are used in pharmaceutical products or to induce vomiting following poisonings (WHO, 2003).

Canadians are exposed to antimony mainly from ingestion of food but also to some extent from water, air, dust, or direct dermal contact with consumer products containing antimony (EURAR, 2008). Concentrations of antimony in meat, freshwater fish, poultry, cereals, fruit, and vegetables appear to range from about 1 to 10 ng/g wet weight; significantly higher levels have been measured in marine organisms (Health Canada, 1997). However, the amount of antimony present in the body is generally low for those not exposed occupationally. Antimony is most commonly measured in blood and urine and this measurement is reflective of exposure to antimony and antimony-related compounds, such as antimony oxide (ATSDR, 1992). An elimination half-life of approximately 95 hours has been estimated after occupational exposures (Kentner et al., 1995). The absorption, distribution, and excretion of antimony depend on both the route of administration and its oxidation state. After inhalation, tissue distribution studies show that the trivalent form accumulates more rapidly than the pentavalent form in the liver, whereas pentavalent antimony is found preferentially in the skeleton. Following ingestion in animals, liver, kidney, bone, lung, spleen, and thyroid are the major sites of accumulation outside the gastrointestinal tract (Health Canada, 1997). In humans, urine accounts for 1.2-3.6 µg of daily antimony excretion. Approximately 0.3-0.9 µg per day (µg/day) is excreted in feces, and less than 1 µg/day is excreted by other routes (Health Canada, 1997). Pentavalent antimony tends to be more readily excreted in the urine than the trivalent form (Elinder & Friberg, 1986).

The low levels of antimony to which the general population is exposed are not expected to cause any adverse health effects (ATSDR, 1992). Chronic occupational exposure to lower doses of antimony compounds is primarily associated with myocardial effects (Health Canada, 1997). Chronic occupational exposure to antimony via inhalation causes damage to the lungs, known as "antimony pneumoconiosis," involving airway obstruction, bronchospasm, and hyperinflation, as well as respiratory irritation and interstitial inflammation. These effects are believed to be primarily due to physiological responses to antimony dust accumulating within the respiratory tract (ATSDR, 1992).

Health Canada and Environment Canada are jointly reviewing and assessing chemical substances as part of the Chemicals Management Plan under the Canadian Environmental Protection Act, 1999. Antimony oxide (CAS 1309-64-4) was identified as a high-priority substance under the Chemicals Management Plan, and a draft screening assessment was published in March 2010 (Government of Canada, 2009; Environment Canada and Health Canada, 2010). The proposed conclusion of the Government of Canada's draft screening assessment is that antimony oxide is not of concern to the environment or to human health at current levels of exposure (Environment Canada & Health Canada, 2010). The International Agency for Research on Cancer (IARC) has classified antimony trioxide as Group 2B (a possible human carcinogen) and antimony trisulphide as Group 3 (not classifiable as to its carcinogenicity to humans) (IARC, 1999). The European Commission has classified antimony trioxide as a Category 3 carcinogenic substance (causes concern for humans owing to possible carcino­genic effects) with "limited evidence for a carcinogenic effect" (EURAR, 2008; ESIS, 2009).

Health Canada (1997) has established a tolerable daily intake of 0.2 µg/kg body weight/day for antimony. Chronic oral exposure to this dose is not expected to lead to significant adverse health effects. A Guideline for Canadian Drinking Water Quality of 0.006 mg/L (6 µg/L) has been established, considering both toxicity and analytical capabilities (Health Canada, 1997).

In a study carried out in 2001 in the region of Québec City, on 500 participants aged 18-65, the 90th percentile value of antimony in urine was 0.28 µg/L. The geometric mean and 90th percentile values of antimony in blood were 5.40 µg/L and 6.22 µg/L, respectively (INSPQ, 2004).

Antimony was measured in the urine of all Canadian Health Measures Survey participants aged 6-79 years and is presented as µg/L urine and µg/g creatinine (Tables 8.1.1a, 8.1.1b). Finding a measurable amount of antimony in urine is an indicator of exposure to antimony or antimony-related compounds and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for urinary levels of antimony in the Canadian population.

Table 8.1.1a
Antimony - Arithmetic and geometric means, and selected percentiles of urine concentrations (µg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 22.40 0.08 0.04 <LOD 0.03 0.05 0.08 0.13 0.18
0.06 - 0.09 0.04 - 0.05 0.02 - 0.03 0.05 - 0.05 0.07 - 0.08 0.12 - 0.14 0.17 - 0.20
6-11 1034 17.99 0.07 0.05 <LOD 0.03 0.06 0.08 0.13 0.18
0.06 - 0.08 0.05 - 0.05 0.03 - 0.04 0.05 - 0.06 0.08 - 0.09 0.10 - 0.16 0.14 - 0.21
12-19 983 12.92 0.09 0.06 <LOD 0.04 0.07 0.10 0.15 0.20
0.07 - 0.11 0.05 - 0.07 0.03 - 0.04 0.06 - 0.07 0.09 - 0.11 0.13 - 0.17 0.17 - 0.23
20-39 1169 25.66 0.09 0.04 <LOD 0.02 0.05 0.08 0.13 0.19
0.05 - 0.12 0.04 - 0.05 <LOD - 0.03 0.04 - 0.05 0.07 - 0.09 0.11 - 0.15 0.15 - 0.23
40-59 1223 27.80 0.07 0.04 <LOD <LOD 0.05 0.07 0.14 0.18
0.05 - 0.09 0.04 - 0.04 0.04 - 0.05 0.07 - 0.08 0.12 - 0.15 0.16 - 0.21
60-79 1083 25.58 0.06 0.04 <LOD <LOD 0.04 0.07 0.11 0.14
0.05 - 0.06 0.04 - 0.04 0.04 - 0.04 0.06 - 0.07 0.10 - 0.12 0.12 - 0.16
Males 
Total,
age 6-79
2662 15.63 0.09 0.05 <LOD 0.03 0.06 0.09 0.14 0.20
0.08 - 0.10 0.05 - 0.06 0.03 - 0.03 0.05 - 0.06 0.08 - 0.10 0.13 - 0.16 0.17 - 0.22
6-11 524 14.12 0.08 0.05 <LOD 0.03 0.06 0.09 0.14 0.18
0.06 - 0.09 0.04 - 0.06 0.03 - 0.04 0.05 - 0.06 0.07 - 0.10 0.09 - 0.19 0.13 - 0.23
12-19 505 8.51 0.10 0.07 0.03 0.04 0.07 0.10 0.16 0.21
0.07 - 0.14 0.06 - 0.07 0.02 - 0.03 0.04 - 0.05 0.06 - 0.08 0.09 - 0.12 0.13 - 0.19 0.14 - 0.27
20-39 514 18.68 0.08 0.05 <LOD 0.03 0.05 0.09 0.14 0.20
0.07 - 0.10 0.04 - 0.06 0.02 - 0.03 0.05 - 0.06 0.08 - 0.11 0.11 - 0.18 0.15 - 0.25
40-59 578 18.34 0.10 0.05 <LOD 0.03 0.05 0.09 0.15 0.21
0.06 - 0.14 0.05 - 0.06 0.03 - 0.04 0.05 - 0.06 0.08 - 0.10 0.13 - 0.18 0.15 - 0.26
60-79 541 17.93 0.07 0.05 <LOD 0.03 0.05 0.08 0.12 0.16
0.06 - 0.08 0.04 - 0.05 0.03 - 0.03 0.04 - 0.05 0.07 - 0.09 0.11 - 0.13 0.12 - 0.20
Females
Total,
age 6-79
2830 28.76 0.06 0.04 <LOD <LOD 0.04 0.07 0.11 0.17
0.04 - 0.08 0.03 - 0.04 0.04 - 0.04 0.06 - 0.07 0.10 - 0.13 0.14 - 0.19
6-11 510 21.96 0.06 0.05 <LOD 0.03 0.05 0.08 0.12 0.17
0.06 - 0.07 0.04 - 0.05 0.02 - 0.04 0.05 - 0.06 0.07 - 0.09 0.11 - 0.13 0.13 - 0.21
12-19 478 17.57 0.07 0.05 <LOD 0.04 0.06 0.09 0.15 0.20
0.06 - 0.08 0.05 - 0.06 0.03 - 0.04 0.06 - 0.07 0.08 - 0.11 0.12 - 0.18 0.15 - 0.24
20-39 655 31.15 0.09 0.04 <LOD <LOD 0.04 0.07 0.11 0.18
0.02 - 0.15 0.04 - 0.04 0.04 - 0.05 0.06 - 0.08 0.09 - 0.13 0.11 - 0.26
40-59 645 36.28 0.05 0.03 <LOD <LOD 0.03 0.06 0.11 0.15
0.04 - 0.06 0.03 - 0.04 0.03 - 0.04 0.05 - 0.07 0.08 - 0.14 0.13 - 0.18
60-79 542 33.21 0.04 0.03 <LOD <LOD 0.03 0.05 0.09 0.12
0.04 - 0.05 0.03 - 0.03 0.03 - 0.04 0.05 - 0.06 0.08 - 0.11 0.10 - 0.14
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.1b
Antimony (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (µg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 22.45 0.08 0.05 <LOD 0.04 0.05 0.07 0.12 0.16
0.07 - 0.09 0.05 - 0.06 0.03 - 0.04 0.05 - 0.05 0.07 - 0.08 0.10 - 0.13 0.14 - 0.18
6-11 1031 18.04 0.09 0.08 <LOD 0.05 0.07 0.11 0.15 0.22
0.09 - 0.10 0.07 - 0.08 0.05 - 0.05 0.07 - 0.08 0.10 - 0.12 0.13 - 0.18 0.16 - 0.28
12-19 982 12.93 0.07 0.05 <LOD 0.04 0.05 0.07 0.10 0.12
0.05 - 0.08 0.05 - 0.06 0.03 - 0.04 0.05 - 0.05 0.06 - 0.08 0.09 - 0.11 0.10 - 0.15
20-39 1165 25.75 0.08 0.05 <LOD 0.03 0.05 0.07 0.12 0.17
0.05 - 0.11 0.05 - 0.05 <LOD - 0.03 0.05 - 0.05 0.06 - 0.08 0.10 - 0.13 0.13 - 0.20
40-59 1218 27.91 0.08 0.05 <LOD <LOD 0.05 0.07 0.12 0.17
0.06 - 0.09 0.05 - 0.06 0.05 - 0.05 0.07 - 0.08 0.10 - 0.15 0.15 - 0.19
60-79 1083 25.58 0.07 0.05 <LOD <LOD 0.05 0.07 0.11 0.14
0.06 - 0.07 0.05 - 0.06 0.05 - 0.05 0.07 - 0.08 0.10 - 0.12 0.13 - 0.16
Males 
Total,
age 6-79
2653 15.68 0.08 0.05 <LOD 0.03 0.05 0.07 0.11 0.16
0.07 - 0.08 0.05 - 0.05 0.03 - 0.04 0.05 - 0.05 0.07 - 0.08 0.10 - 0.13 0.13 - 0.19
6-11 522 14.18 0.10 0.08 <LOD 0.05 0.08 0.11 0.16 0.24
0.09 - 0.11 0.08 - 0.09 0.05 - 0.06 0.07 - 0.08 0.10 - 0.12 0.12 - 0.20 0.11 - 0.36
12-19 504 8.53 0.07 0.06 0.03 0.04 0.06 0.07 0.10 0.12
0.05 - 0.10 0.05 - 0.06 0.03 - 0.03 0.04 - 0.04 0.05 - 0.06 0.07 - 0.08 0.08 - 0.11 0.10 - 0.15
20-39 512 18.75 0.07 0.05 <LOD 0.03 0.04 0.07 0.12 0.16
0.06 - 0.07 0.04 - 0.05 0.03 - 0.03 0.04 - 0.05 0.06 - 0.08 0.10 - 0.13 0.12 - 0.21
40-59 574 18.47 0.08 0.05 <LOD 0.03 0.05 0.07 0.10 0.16
0.05 - 0.11 0.05 - 0.06 0.03 - 0.04 0.05 - 0.06 0.06 - 0.08 0.08 - 0.13 0.11 - 0.21
60-79 541 17.93 0.06 0.05 <LOD 0.03 0.05 0.07 0.10 0.14
0.06 - 0.07 0.05 - 0.05 0.03 - 0.04 0.04 - 0.05 0.06 - 0.07 0.09 - 0.12 0.11 - 0.16
Females
Total,
age 6-79
2826 28.80 0.08 0.06 <LOD <LOD 0.05 0.07 0.12 0.17
0.06 - 0.10 0.05 - 0.06 0.05 - 0.06 0.07 - 0.08 0.10 - 0.14 0.14 - 0.20
6-11 509 22.00 0.09 0.07 <LOD 0.05 0.07 0.10 0.14 0.19
0.08 - 0.10 0.07 - 0.08 0.05 - 0.06 0.07 - 0.07 0.08 - 0.11 0.12 - 0.17 0.15 - 0.23
12-19 478 17.57 0.06 0.05 <LOD 0.03 0.05 0.06 0.09 0.12
0.05 - 0.07 0.04 - 0.05 0.03 - 0.04 0.04 - 0.05 0.05 - 0.07 0.08 - 0.11 0.05 - 0.19
20-39 653 31.24 0.09 0.05 <LOD <LOD 0.05 0.07 0.11 0.17
0.04 - 0.14 0.05 - 0.06 0.05 - 0.05 0.07 - 0.08 0.09 - 0.14 0.09 - 0.24
40-59 644 36.34 0.07 0.06 <LOD <LOD 0.05 0.07 0.13 0.17
0.06 - 0.08 0.05 - 0.06 0.05 - 0.06 0.06 - 0.08 0.11 - 0.16 0.14 - 0.20
60-79 542 33.21 0.07 0.06 <LOD <LOD 0.06 0.08 0.11 0.15
0.06 - 0.08 0.05 - 0.06 0.05 - 0.06 0.07 - 0.09 0.10 - 0.12 0.12 - 0.17
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.2 Arsenic (CASRN 7440-38-2)

Arsenic (As) is a naturally occurring element that comprises a small fraction of the Earth's crust (ATSDR, 2007). It is classified as a metalloid, exhibiting properties of both a metal and a non-metal. Arsenic has oxidation states of -3, 0, +3, and +5, and is commonly found as an inorganic sulphide complexed with other metals (CCME, 1997). Arsenic also forms stable organic compounds in its trivalent (+3) and pentavalent (+5) states.

The primary anthropogenic sources of arsenic released to the environment are the smelting of metal ores, the use of arsenical pesticides, and the burning of fossil fuels. Arsenic may enter lakes, rivers, or groundwater naturally, when mineral deposits or rocks containing arsenic dissolve. In Canada, gold ores are the primary anthropogenic source of arsenic (Environment Canada & Health Canada, 1993). Arsenic is used in the manufacture of transistors, lasers, and semi-conductors, and in the processing of glass, pigments, textiles, paper, metal adhesives, ceramics, wood preservatives, ammunition, and explosives. Historical uses of arsenic include application of lead arsenate as a pesticide in apple orchards and vineyards, and arsenic trioxide as a herbicide (Health Canada, 2006; ATSDR, 2007). Chromated copper arsenate was formerly used as a wood preservative in residential construction projects such as playground structures and decks; however, it is now used only for industrial purposes and for domestic wood foundations (PMRA, 2005).

The public is exposed to arsenic in food, drinking water, soil, and ambient air, with food (particularly meat and fish) representing the major source of intake (Environment Canada & Health Canada, 1993). Exposure may also arise from indoor house dust, as levels in dust can exceed levels in soil (Rasmussen et al., 2001). Although shellfish and marine species have been found to bioconcentrate arsenic, it is not biomagnified through the food chain (ATSDR, 2007). Exposure to arsenic may be elevated in populations residing in the vicinity of industrial and geological sources. Arsenic can be found in both surface water and groundwater sources, with levels generally higher in groundwater. Drinking water is considered to be the major source of exposure to arsenic only in populations living near a source of arsenic (either a natural geological source or a site of contamination). Smokers are also exposed to arsenic in cigarettes, although it is considered to be of minor importance for arsenic absorption (Schneider & Krivan, 1993).

Arsenic compounds are readily absorbed in the gastrointestinal tract (~45-90%) (Pomroy et al., 1980; Yamauchi et al., 1986). Following oral ingestion, inorganic arsenic appears rapidly in the circulation, where it binds primarily to hemoglobin. Within 24 hours, it is found mainly in the liver, kidneys, lungs, spleen, and skin. Skin, bone, and muscle represent the major storage sites. In cases of chronic exposure, arsenic will preferentially accumulate in tissues rich in keratin and/or sulfhydryl (thiol) groups, such as hair, nails, skin, and other protein-containing tissues (Human Biomonitoring Commission of the German Federal Environmental Agency, 2003). The half-life of inorganic arsenic in humans is estimated to be between two and 40 days (Health Canada, 2006). A considerable portion of inorganic arsenic is eliminated from the body by the rapid urinary excretion of non-methylated arsenic in both trivalent and pentavalent forms and by sequential methylation of arsenic (+3) to monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA) in the liver (WHO, 1996).

Measurements of arsenic in urine are useful biological indicators of exposure (ATSDR, 2007). Measurement of urinary arsenic levels is generally accepted as the most reliable indicator of recent arsenic exposure, since arsenic absorbed from the lungs or the gastrointestinal tract is excreted in the urine within one to two days, while arsenic is cleared from blood within a few hours (ATSDR, 2007). Measurements of arsenic in urine have been used to identify recent arsenic ingestion or above-average exposures in populations living near industrial point sources of arsenic. Arsenic levels can also be measured in the blood; however, blood arsenic levels are not as well correlated with drinking water concentrations as are urine arsenic levels (Valentine et al., 1979).

While the majority of assessments on the toxicity of arsenic have concentrated on the inorganic forms, recent studies have highlighted the potential for organic arsenic compounds, in particular the trivalent monomethylated arsenic (MMAIII), to also exert adverse health effects (Cohen et al., 2006; Schwedtle et al., 2003). Further research is required to confirm these findings (Health Canada, 2006). Inhalation of inorganic arsenic has been associated with respiratory cancer for workers in smelters and production facilities for arsenical pesticides (Environment Canada & Health Canada, 1993). Chronic ingestion of arsenic has also been associated with non-cancer effects on the skin (Environment Canada & Health Canada, 1993), cardiovascular effects including increased incidence of high blood pressure and circulatory problems, and decreased lung function (ATSDR, 2007).

Health Canada and Environment Canada concluded that current concentrations of inorganic arsenic in Canada may be harmful to the environment and to human health (Environment Canada & Health Canada, 1993). Arsenic is classified as a human carcinogen (Group I) by Health Canada (2006) and other international agencies (IARC, 2004; US EPA, 1998). Health Canada has established a maximum acceptable concentration for arsenic in drinking water of 0.010 mg/L based on the incidence of internal (lung, bladder, and liver) cancers in humans and taking into consideration the ability of currently available technologies to remove arsenic from drinking water (Health Canada, 2006).

In a study carried out in British Columbia to assess the levels of trace elements in 61 non-smoking adults aged 30-65, the geometric mean concentration and 95th percentile of total arsenic in urine were 27.8 µg/g creatinine and 175.5 µg/g creatinine, respectively (Clark et al., 2007). In a separate study carried out in the region of Québec City on 500 adults aged 18-65, the geometric mean and 90th percentile values of total arsenic in urine were 12.73 µg/L and 65.18 µg/L, respectively. The geometric mean and 90th percentile values of arsenic in blood were 0.95 µg/L and 2.82 µg/L, respectively (INSPQ, 2004).

Total arsenic was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey (CHMS) and is presented as µg/L in blood and as both µg/L and µg/g creatinine in urine (Tables 8.1.2a, 8.1.2b, 8.1.2c). Finding a measurable amount of arsenic in blood or urine is an indicator of exposure to arsenic and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for blood and urinary levels of total arsenic in the Canadian population.

Table 8.1.2a
Arsenic - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 7.24 1.41 0.89 0.31 0.54 0.86 1.48 2.70 4.08
1.11 - 1.72 0.74 - 1.06 <LOD - 0.41 0.42 - 0.66 0.72 - 1.01 1.20 - 1.76 1.94 - 3.46 2.94 - 5.23
6-11 910 10.77 0.85 0.59 <LOD 0.38 0.66 0.98 1.51 2.16
0.72 - 0.98 0.48 - 0.74 0.24 - 0.52 0.52 - 0.79 0.84 - 1.12 1.14 - 1.88 1.16 - 3.15
12-19 945 10.90 0.89 0.59 <LOD 0.38 0.66 0.96 1.51 1.83
0.57 - 1.21 0.46 - 0.75 0.29 - 0.48 0.50 - 0.81 0.73 - 1.19 1.09 - 1.93 0.99 - 2.66
20-39 1165 6.78 1.28 0.86 0.30 0.54 0.86 1.48 2.45 3.57
1.01 - 1.55 0.72 - 1.04 <LOD - 0.39 0.43 - 0.66 0.71 - 1.01 1.15 - 1.81 1.63 - 3.27 2.50 - 4.64
40-59 1220 4.84 1.63 0.99 0.34 0.60 0.95 1.61 3.04 4.70
1.18 - 2.08 0.81 - 1.20 <LOD - 0.47 0.47 - 0.73 0.79 - 1.11 1.28 - 1.93 2.05 - 4.03 2.48 - 6.93
60-79 1079 4.26 1.77 1.12 0.41 0.63 1.06 1.95 3.56 5.11
1.31 - 2.22 0.91 - 1.38 0.29 - 0.53 0.51 - 0.75 0.82 - 1.31 1.37 - 2.54 2.52 - 4.60 3.51 - 6.71
Males 
Total,
age 6-79
2576 6.72 1.43 0.89 0.31 0.54 0.85 1.48 2.72 3.97
1.11 - 1.74 0.75 - 1.06 <LOD - 0.40 0.44 - 0.65 0.70 - 1.00 1.18 - 1.78 1.93 - 3.50 2.76 - 5.17
6-11 459 11.11 0.76 0.56 <LOD 0.35 0.62 0.92 1.34 1.89
0.56 - 0.97 0.41 - 0.75 <LOD - 0.51 0.44 - 0.80 0.69 - 1.16 0.77 - 1.91 1.28 - 2.50
12-19 489 11.66 0.88 0.58 <LOD 0.38 0.64 0.95 1.49 1.66
0.43 - 1.34 0.44 - 0.75 0.29 - 0.48 0.48 - 0.79 0.66 - 1.24 1.09 - 1.89 0.24 - 3.08
20-39 514 4.67 1.22 0.85 0.31 0.55 0.84 1.46 2.25 3.37
0.96 - 1.48 0.70 - 1.03 0.23 - 0.39 0.43 - 0.66 0.69 - 0.99 1.08 - 1.83 1.31 - 3.20 2.11 - 4.62
40-59 577 4.33 1.77 1.03 0.39 0.61 0.96 1.62 3.25 5.01
1.20 - 2.34 0.87 - 1.23 0.27 - 0.52 0.50 - 0.73 0.77 - 1.16 1.30 - 1.94 2.38 - 4.12 2.24 - 7.79
60-79 537 2.98 1.76 1.16 0.41 0.66 1.13 1.98 3.55 4.97
1.35 - 2.16 0.96 - 1.40 0.31 - 0.52 0.52 - 0.79 0.83 - 1.43 1.42 - 2.54 2.46 - 4.65 3.49 - 6.46
Females
Total,
age 6-79
2743 7.73 1.40 0.88 0.29 0.53 0.89 1.48 2.67 4.19
1.09 - 1.71 0.73 - 1.07 <LOD - 0.41 0.40 - 0.67 0.74 - 1.03 1.21 - 1.76 1.84 - 3.50 2.89 - 5.49
6-11 451 10.42 0.94 0.64 <LOD 0.40 0.68 1.03 1.65 3.13
0.80 - 1.09 0.54 - 0.75 0.27 - 0.52 0.56 - 0.81 0.94 - 1.13 0.98 - 2.32 1.71 - 4.55
12-19 456 10.09 0.90 0.61 <LOD 0.39 0.66 0.96 1.54 1.96
0.65 - 1.14 0.47 - 0.78 0.27 - 0.50 0.50 - 0.83 0.75 - 1.16 1.07 - 2.00 1.40 - 2.52
20-39 651 8.45 1.35 0.88 0.30 0.53 0.88 1.47 2.56 4.00
0.99 - 1.70 0.71 - 1.07 <LOD - 0.41 0.39 - 0.66 0.69 - 1.07 1.17 - 1.78 1.62 - 3.51 2.23 - 5.77
40-59 643 5.29 1.49 0.95 0.33 0.57 0.95 1.57 2.83 4.49
1.12 - 1.86 0.75 - 1.20 <LOD - 0.46 0.38 - 0.76 0.78 - 1.11 1.15 - 1.99 1.73 - 3.93 2.52 - 6.46
60-79 542 5.54 1.77 1.09 0.40 0.62 1.04 1.90 3.57 5.28
1.22 - 2.33 0.86 - 1.39 0.24 - 0.57 0.50 - 0.73 0.82 - 1.26 1.16 - 2.64 2.26 - 4.87 2.90 - 7.65
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.2b
Arsenic - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 0.18 23.07 12.00 3.20 5.85 11.67 23.77 44.18 70.63
17.67 - 28.48 10.16 - 14.17 2.90 - 3.49 5.06 - 6.64 9.26 - 14.07 18.59 - 28.95 36.80 - 51.57 51.87 - 89.39
6-11 1034 0.10 18.65 9.66 2.46 4.82 9.63 18.59 35.42 51.31
13.82 - 23.48 8.16 - 11.44 1.83 - 3.08 3.80 - 5.83 7.66 - 11.61 14.85 - 22.33 28.37 - 42.47 27.81 - 74.81
12-19 983 0.31 22.58 11.88 3.51 6.61 11.37 21.44 37.40 55.57
9.91 - 35.25 9.96 - 14.16 2.74 - 4.27 5.73 - 7.49 9.05 - 13.68 15.11 - 27.76 23.86 - 50.94 30.29 - 80.86
20-39 1169 0.09 22.47 12.08 3.03 5.86 12.06 25.04 45.11 66.97
17.82 - 27.12 10.44 - 13.99 2.60 - 3.45 5.04 - 6.67 10.17 - 13.94 17.88 - 32.20 37.50 - 52.71 47.15 - 86.79
40-59 1223 0.41 24.99 12.60 3.26 6.08 12.18 24.95 44.94 77.68
18.10 - 31.89 10.45 - 15.19 2.85 - 3.68 4.81 - 7.34 9.07 - 15.29 19.53 - 30.38 37.25 - 52.62 46.76 - 108.61
60-79 1083 0.00 22.59 11.85 3.59 5.66 11.27 22.73 46.02 72.72
16.08 - 29.11 9.30 - 15.10 3.01 - 4.18 4.38 - 6.95 7.34 - 15.20 16.96 - 28.49 27.21 - 64.83 48.74 - 96.69
Males 
Total,
age 6-79
2662 0.23 24.73 13.31 3.73 6.82 12.62 25.82 46.92 73.44
18.02 - 31.43 11.08 - 15.99 3.36 - 4.10 5.66 - 7.97 9.39 - 15.85 19.27 - 32.38 38.23 - 55.61 50.40 - 96.49
6-11 524 0.19 18.39 9.61 2.48 5.21 9.64 17.67 33.32 50.89
10.30 - 26.49 7.12 - 12.99 1.23 - 3.73 3.72 - 6.70 7.14 - 12.14 11.62 - 23.72 20.80 - 45.83 26.10 - 75.69
12-19 505 0.40 23.44 11.79 3.81 6.82 10.90 20.51 33.41 52.73
2.33 - 44.55 9.48 - 14.67 2.99 - 4.62 6.10 - 7.54 8.36 - 13.44 15.23 - 25.78 20.64 - 46.18 6.60 - 98.85
20-39 514 0.19 21.68 13.06 3.59 6.13 12.67 28.04 48.54 66.70
17.36 - 26.00 11.09 - 15.39 2.97 - 4.20 4.96 - 7.31 9.79 - 15.55 18.71 - 37.38 36.15 - 60.93 47.65 - 85.75
40-59 578 0.35 29.07 15.01 4.17 7.89 14.46 29.87 47.53 94.70
18.93 - 39.22 11.96 - 18.83 3.00 - 5.35 6.21 - 9.58 9.96 - 18.95 22.21 - 37.52 30.65 - 64.41 48.42 - 140.99
60-79 541 0.00 25.42 13.65 3.84 6.84 13.61 25.66 47.27 75.45
16.90 - 33.95 10.29 - 18.12 2.84 - 4.85 4.80 - 8.87 9.11 - 18.10 18.97 - 32.35 21.82 - 72.73 44.85 - 106.05
Females
Total,
age 6-79
2830 0.14 21.42 10.81 2.80 5.12 10.81 21.98 41.43 67.50
16.86 - 25.99 9.27 - 12.61 2.36 - 3.24 4.44 - 5.79 8.84 - 12.78 18.07 - 25.88 33.99 - 48.88 49.41 - 85.58
6-11 510 0.00 18.92 9.72 2.21 4.42 9.51 19.78 35.89 52.47
13.88 - 23.97 8.21 - 11.50 1.50 - 2.93 3.44 - 5.40 7.13 - 11.90 16.00 - 23.57 28.73 - 43.05 9.29 - 95.66
12-19 478 0.21 21.64 11.98 3.08 5.87 12.05 23.59 42.57 57.19
14.38 - 28.90 9.79 - 14.66 1.43 - 4.74 4.09 - 7.65 9.09 - 15.01 14.56 - 32.63 27.61 - 57.53 37.45 - 76.93
20-39 655 0.00 23.26 11.17 2.37 5.12 11.48 22.26 43.16 67.61
16.58 - 29.93 9.49 - 13.15 1.73 - 3.00 3.96 - 6.29 10.04 - 12.92 17.17 - 27.35 33.96 - 52.36 35.93 - 99.29
40-59 645 0.47 20.95 10.60 2.88 4.68 9.78 22.71 41.24 70.71
15.85 - 26.06 8.97 - 12.53 2.40 - 3.37 3.83 - 5.53 7.30 - 12.26 18.54 - 26.88 34.72 - 47.75 46.91 - 94.51
60-79 542 0.00 20.00 10.40 3.24 5.07 9.35 20.05 38.62 70.46
14.69 - 25.30 8.14 - 13.30 2.30 - 4.19 3.95 - 6.19 6.03 - 12.67 14.73 - 25.37 20.18 - 57.07 46.01 - 94.92
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.2c
Arsenic (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 0.18 25.82 14.24 4.74 7.45 13.07 24.43 46.49 67.76
18.00 - 33.65 11.44 - 17.72 3.93 - 5.54 5.93 - 8.97 10.09 - 16.05 18.70 - 30.16 33.74 - 59.24 45.70 - 89.82
6-11 1031 0.10 25.35 14.76 5.41 7.85 13.22 24.51 42.59 59.33
18.41 - 32.29 12.23 - 17.80 4.60 - 6.22 6.15 - 9.55 10.10 - 16.33 19.02 - 29.99 33.60 - 51.58 15.61 - 103.05
12-19 982 0.31 15.95 9.82 3.73 5.51 9.25 16.05 29.06 35.75
7.06 - 24.85 7.68 - 12.56 3.09 - 4.36 4.31 - 6.71 6.91 - 11.60 11.49 - 20.60 19.19 - 38.94 20.15 - 51.35
20-39 1165 0.09 22.01 13.35 4.57 7.03 12.52 23.64 42.92 60.29
16.54 - 27.49 10.80 - 16.50 3.84 - 5.30 5.72 - 8.34 9.41 - 15.63 17.84 - 29.45 30.82 - 55.02 39.57 - 81.00
40-59 1218 0.41 31.34 15.72 5.11 8.47 14.26 25.98 50.88 75.15
17.30 - 45.37 12.47 - 19.81 3.72 - 6.51 6.90 - 10.03 10.83 - 17.68 20.79 - 31.17 32.15 - 69.61 15.17 - 135.13
60-79 1083 0.00 28.55 16.57 5.41 7.88 14.86 29.82 56.24 86.85
20.16 - 36.95 12.60 - 21.78 4.41 - 6.42 5.10 - 10.67 9.64 - 20.08 17.51 - 42.13 39.53 - 72.96 57.07 - 116.63
Males 
Total,
age 6-79
2653 0.23 25.11 12.85 4.49 6.82 11.50 22.05 38.39 60.03
15.59 - 34.63 10.34 - 15.96 3.68 - 5.29 5.46 - 8.18 8.66 - 14.34 17.14 - 26.96 25.59 - 51.18 41.58 - 78.47
6-11 522 0.19 25.11 14.34 5.52 7.43 12.45 23.16 42.80 56.29
13.72 - 36.50 11.30 - 18.20 4.61 - 6.43 5.71 - 9.15 8.43 - 16.47 16.52 - 29.79 28.70 - 56.90 11.90 - 100.69
12-19 504 0.40 16.61 9.47 3.47 5.14 8.98 15.78 29.69 35.21
2.63 - 30.60 7.25 - 12.36 2.61 - 4.32 3.70 - 6.57 6.88 - 11.07 11.03 - 20.54 19.13 - 40.24 20.28 - 50.14
20-39 512 0.20 17.88 11.73 4.10 6.65 10.82 21.40 33.17 48.48
13.83 - 21.93 9.42 - 14.60 2.91 - 5.29 5.06 - 8.25 8.06 - 13.59 15.96 - 26.83 23.71 - 42.63 39.11 - 57.86
40-59 574 0.35 35.23 14.36 4.74 7.56 12.57 23.65 44.13 70.40
13.86 - 56.60 11.27 - 18.29 3.42 - 6.06 5.97 - 9.14 9.04 - 16.11 18.25 - 29.04 20.99 - 67.27 <LOD - 143.82
60-79 541 0.00 24.23 14.40 5.15 7.31 12.98 23.80 47.22 72.72
17.40 - 31.06 11.22 - 18.47 4.27 - 6.03 5.58 - 9.05 8.83 - 17.13 16.86 - 30.74 29.09 - 65.36 41.06 - 104.37
Females
Total,
age 6-79
2826 0.14 26.54 15.78 5.07 8.18 14.55 27.31 50.89 79.61
19.77 - 33.30 12.61 - 19.75 4.14 - 6.01 6.45 - 9.92 11.25 - 17.85 19.62 - 35.00 37.06 - 64.72 53.80 - 105.43
6-11 509 0.00 25.60 15.20 5.31 8.40 13.73 25.38 41.66 61.26
18.45 - 32.75 12.59 - 18.36 4.08 - 6.54 6.50 - 10.29 10.77 - 16.69 19.15 - 31.61 31.55 - 51.77 <LOD - 128.24
12-19 478 0.21 15.24 10.23 4.06 5.74 9.41 16.40 29.06 38.71
10.73 - 19.75 7.89 - 13.26 3.33 - 4.79 4.39 - 7.08 6.51 - 12.31 11.41 - 21.38 19.19 - 38.93 22.74 - 54.67
20-39 653 0.00 26.18 15.21 4.88 7.61 14.26 26.96 48.78 79.61
17.98 - 34.39 12.10 - 19.12 4.06 - 5.70 6.31 - 8.90 11.29 - 17.22 18.03 - 35.88 32.70 - 64.87 42.95 - 116.26
40-59 644 0.47 27.50 17.19 5.66 9.51 15.95 28.05 53.24 85.99
19.67 - 35.33 13.54 - 21.82 3.78 - 7.55 6.88 - 12.14 11.55 - 20.34 21.82 - 34.27 37.99 - 68.49 35.84 - 136.14
60-79 542 0.00 32.53 18.85 5.78 9.32 17.13 36.96 64.77 95.97
22.15 - 42.90 13.83 - 25.70 4.15 - 7.40 5.80 - 12.83 10.20 - 24.07 23.41 - 50.50 47.58 - 81.97 57.56 - 134.39
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.3 Cadmium (CASRN 7440-43-9)

Cadmium (Cd) is a naturally occurring soft, silvery white, blue tinged metal. It is among the least abundant trace metals and often occurs in zinc ores. Canadian zinc ores typically contain 0.001-0.067% recoverable cadmium (Environment Canada, 1972). Common forms of cadmium include soluble and insoluble species, which may also be found as particulate matter in the atmosphere (CCME, 1996; ATSDR, 1999).

Most of the cadmium released into the environment is the result of anthropogenic activities; however, cadmium also enters the environment as a result of natural processes, including forest fires, volcanic emissions, and weathering of soil and bedrock. The main sources of cadmium emitted into the atmosphere are from industrial base-metal smelting and refining processes, and combustion processes, such as coal-fired electrical plants and waste incineration where cadmium is released as a by-product (CCME, 1996).

Cadmium is primarily used in manufacture of nickel-cadmium batteries. It is also used in industrial coatings and electroplating, in pigments, and as a plastic stabilizer in PVC plastics. Cadmium is present in metal alloy sheets, wires, rods, solders, and shields for various industrial applications (Environment Canada & Health Canada, 1994). It is frequently an impurity in galvanized pipes and can leach into drinking water (Health Canada, 1986). Cadmium is sometimes used as a pigment in ceramic glazes. In Canada, the leachable cadmium content of glazed ceramics and glassware is regulated under the Hazardous Products Act (Health Canada, 2006). The Act also limits the leachable cadmium content of paints and other surface coatings on toys and other products for use by a child in learning or play to 1000 mg/kg (Health Canada, 2009).

Inhalation of cigarette smoke is the major source of cadmium exposure in smokers. The tobacco of one typical Canadian cigarette contains approximately 1 µg of cadmium, of which 6-20% may be transferred in mainstream smoke (Hammond & O'Connor, 2008). Smoking 20 cigarettes per day can therefore result in an additional daily exposure of approximately 1.2-4 µg of cadmium. Non-smokers are primarily exposed to cadmium through food, although occupational exposure can also be a significant source. Cadmium can also be present in drinking water; other minor exposure pathways include inhalation and leaching/releases from consumer products (Environment Canada & Health Canada, 1994; ATSDR, 1999).

Absorption of cadmium in the body depends on the levels of other components of the diet, such as iron, calcium, and protein. The total amount absorbed by humans has been estimated to be between 0.2 and 0.5 µg/day. Absorbed cadmium accumulates mainly in the renal cortex and liver, with concentrations in the renal cortex approximately 5-20 times those in the liver. Only a small proportion of absorbed cadmium is eliminated, mainly in the urine and feces, although small amounts are also eliminated through hair, nails, and sweat. The biological half-life of cadmium has been estimated to be approximately 10-12 years (Amzal et al., 2009; Lauwerys et al., 1994).

Cadmium can be measured in blood, urine, feces, liver, kidney, and hair, among other tissues. Cadmium concentrations in urine best reflect the total body burden of cadmium (i.e., cumulative exposure), although they fluctuate slightly due to recent exposures. American studies indicate that non-smokers have urinary cadmium concentrations of approximately 0.35 μg/g creatinine in the absence of high environmental or occupational exposure (ATSDR, 1999). Concentrations of cadmium in blood reflect both recent and cumulative exposures (CDC, 2005). Typical concentrations in blood are approximately 0.4 to 1 μg/L for non-smokers. Smoking and occupational exposures can elevate blood concentrations (ATSDR, 1999).

Health Canada and Environment Canada concluded that inorganic cadmium compounds are a concern for human health (Environment Canada and Health Canada, 1994). Cadmium and its compounds have been classified as human carcinogens (Group 1) by the International Agency for Research on Cancer (IARC, 1997), with exposure to high levels by inhalation primarily associated with lung cancer. Cadmium is also a respiratory irritant when high concentrations are present in workplace air, and chronic inhalation exposure has been associated with lung effects, including emphysema, and kidney effects. Oral exposure to high doses of cadmium may cause severe gastrointestinal irritation and kidney effects (ATSDR, 1999). On the basis of health considerations, Health Canada has established a maximum acceptable concentration (MAC) of 0.005 mg/L (5 µg/L) cadmium in drinking water (Health Canada, 1986).

In a study carried out in the region of Québec City on adults aged 18-65, the geometric mean and 90th percentile values of cadmium in urine were 0.54 µg/L and 1.26 µg/L, respectively. The geometric mean and 90th percentile values of cadmium in blood were 0.69 µg/L and 3.43 µg/L, respectively (INSPQ, 2004).

Cadmium was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L in blood and as both µg/L and µg/g creatinine in urine (Tables 8.1.3a, 8.1.3b, 8.1.3c). Finding a measurable amount of cadmium in blood or urine is an indicator of exposure to cadmium and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for blood and urinary levels of cadmium in the Canadian population.

Table 8.1.3a
Cadmium - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 2.91 0.77 0.35 0.10 0.15 0.28 0.63 2.42 3.63
0.69 - 0.84 0.32 - 0.38 0.09 - 0.11 0.14 - 0.17 0.25 - 0.30 0.55 - 0.71 2.01 - 2.83 3.14 - 4.12
6-11 910 9.12 0.11 0.10 0.05 0.08 0.10 0.14 0.19 0.23
0.10 - 0.13 0.09 - 0.11 <LOD - 0.06 0.07 - 0.08 0.09 - 0.11 0.12 - 0.15 0.16 - 0.22 0.19 - 0.26
12-19 945 3.92 0.35 0.17 0.07 0.11 0.15 0.22 0.52 1.45
0.17 - 0.53 0.14 - 0.21 0.05 - 0.09 0.09 - 0.12 0.13 - 0.16 0.19 - 0.24 0.07 - 0.97 <LOD - 3.05
20-39 1165 1.55 0.81 0.35 0.10 0.15 0.24 0.68 2.63 3.43
0.71 - 0.91 0.31 - 0.39 0.09 - 0.12 0.13 - 0.16 0.22 - 0.27 0.43 - 0.93 2.10 - 3.15 3.11 - 3.76
40-59 1220 0.90 1.00 0.49 0.14 0.21 0.37 1.00 3.16 4.21
0.86 - 1.13 0.44 - 0.54 0.12 - 0.16 0.19 - 0.23 0.32 - 0.41 0.71 - 1.28 2.34 - 3.97 3.71 - 4.71
60-79 1079 0.56 0.73 0.45 0.18 0.25 0.39 0.71 1.73 2.76
0.63 - 0.84 0.42 - 0.49 0.17 - 0.19 0.24 - 0.26 0.38 - 0.41 0.60 - 0.83 1.20 - 2.26 2.26 - 3.25
Males 
Total,
age 6-79
2576 3.34 0.73 0.31 0.09 0.14 0.23 0.58 2.35 3.48
0.62 - 0.83 0.28 - 0.35 0.08 - 0.10 0.12 - 0.15 0.20 - 0.25 0.44 - 0.73 1.90 - 2.80 2.89 - 4.07
6-11 459 9.59 0.11 0.09 0.05 0.07 0.10 0.13 0.19 0.21
0.10 - 0.13 0.08 - 0.10 <LOD - 0.07 0.07 - 0.08 0.09 - 0.11 0.12 - 0.15 0.16 - 0.22 0.16 - 0.27
12-19 489 3.48 0.37 0.16 0.06 0.10 0.14 0.21 0.51 1.54
0.14 - 0.60 0.13 - 0.20 0.04 - 0.08 0.08 - 0.12 0.12 - 0.16 0.18 - 0.24 <LOD - 1.18 <LOD - 3.80
20-39 514 2.14 0.85 0.33 0.09 0.13 0.21 0.77 2.86 3.63
0.72 - 0.98 0.27 - 0.41 0.06 - 0.11 0.11 - 0.15 0.16 - 0.26 0.39 - 1.14 2.10 - 3.62 3.17 - 4.09
40-59 577 1.73 0.88 0.40 0.12 0.18 0.28 0.86 2.83 3.87
0.65 - 1.10 0.33 - 0.49 0.09 - 0.14 0.15 - 0.21 0.24 - 0.31 0.33 - 1.38 1.74 - 3.91 2.84 - 4.91
60-79 537 0.74 0.67 0.41 0.16 0.23 0.35 0.66 1.68 2.73
0.53 - 0.81 0.35 - 0.48 0.14 - 0.18 0.21 - 0.24 0.31 - 0.39 0.44 - 0.89 0.96 - 2.41 1.86 - 3.60
Females
Total,
age 6-79
2743 2.52 0.81 0.39 0.11 0.18 0.33 0.65 2.52 3.73
0.72 - 0.89 0.36 - 0.42 0.10 - 0.12 0.16 - 0.20 0.29 - 0.37 0.57 - 0.74 2.06 - 2.98 3.11 - 4.35
6-11 451 8.65 0.12 0.10 0.05 0.08 0.11 0.14 0.19 0.23
0.10 - 0.13 0.09 - 0.11 <LOD - 0.07 0.07 - 0.09 0.10 - 0.11 0.12 - 0.15 0.15 - 0.23 0.19 - 0.27
12-19 456 4.39 0.33 0.18 0.08 0.11 0.16 0.23 0.56 1.32
0.19 - 0.46 0.15 - 0.22 0.07 - 0.10 0.09 - 0.12 0.13 - 0.18 0.20 - 0.27 0.20 - 0.91 0.05 - 2.59
20-39 651 1.08 0.77 0.36 0.11 0.17 0.27 0.63 2.49 3.24
0.63 - 0.90 0.32 - 0.41 0.10 - 0.13 0.14 - 0.19 0.23 - 0.32 0.45 - 0.81 1.93 - 3.05 2.74 - 3.75
40-59 643 0.16 1.12 0.58 0.19 0.27 0.44 1.12 3.70 4.43
0.95 - 1.29 0.51 - 0.66 0.16 - 0.22 0.24 - 0.31 0.37 - 0.50 0.66 - 1.58 2.86 - 4.55 3.92 - 4.94
60-79 542 0.37 0.79 0.49 0.19 0.28 0.43 0.76 1.77 2.75
0.65 - 0.93 0.44 - 0.56 0.17 - 0.22 0.25 - 0.31 0.37 - 0.48 0.65 - 0.88 0.97 - 2.57 1.90 - 3.59
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.3b
Cadmium - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5491 9.71 0.55 0.35 0.09 0.20 0.38 0.68 1.16 1.65
0.52 - 0.58 0.32 - 0.38 <LOD - 0.11 0.17 - 0.22 0.35 - 0.41 0.63 - 0.72 1.06 - 1.27 1.54 - 1.75
6-11 1033 14.71 0.31 0.22 <LOD 0.13 0.25 0.42 0.59 0.72
0.26 - 0.37 0.19 - 0.26 0.10 - 0.16 0.21 - 0.29 0.38 - 0.47 0.52 - 0.65 0.60 - 0.85
12-19 983 10.48 0.37 0.27 <LOD 0.18 0.32 0.48 0.68 0.89
0.32 - 0.42 0.24 - 0.31 0.15 - 0.21 0.28 - 0.36 0.43 - 0.54 0.58 - 0.78 0.65 - 1.13
20-39 1169 13.17 0.43 0.28 <LOD 0.17 0.32 0.54 0.92 1.20
0.39 - 0.47 0.25 - 0.31 0.14 - 0.20 0.28 - 0.36 0.49 - 0.59 0.83 - 1.01 1.04 - 1.35
40-59 1223 7.36 0.67 0.42 0.11 0.25 0.46 0.81 1.51 2.10
0.62 - 0.72 0.38 - 0.47 <LOD - 0.14 0.21 - 0.28 0.40 - 0.51 0.74 - 0.88 1.35 - 1.68 1.75 - 2.44
60-79 1083 3.14 0.77 0.50 0.14 0.28 0.52 0.99 1.61 2.30
0.69 - 0.85 0.45 - 0.56 0.11 - 0.17 0.24 - 0.32 0.47 - 0.57 0.88 - 1.09 1.41 - 1.81 1.93 - 2.67
Males 
Total,
age 6-79
2661 8.27 0.55 0.36 0.10 0.21 0.39 0.69 1.16 1.58
0.51 - 0.59 0.33 - 0.39 <LOD - 0.12 0.19 - 0.23 0.36 - 0.43 0.63 - 0.75 1.05 - 1.28 1.44 - 1.73
6-11 523 13.00 0.31 0.23 <LOD 0.15 0.26 0.42 0.60 0.71
0.26 - 0.36 0.19 - 0.27 0.12 - 0.18 0.19 - 0.33 0.37 - 0.48 0.54 - 0.65 0.59 - 0.83
12-19 505 8.12 0.35 0.27 0.10 0.20 0.31 0.45 0.62 0.77
0.31 - 0.40 0.24 - 0.31 <LOD - 0.11 0.16 - 0.23 0.27 - 0.35 0.39 - 0.52 0.50 - 0.74 0.55 - 0.99
20-39 514 11.87 0.41 0.29 <LOD 0.17 0.33 0.54 0.92 1.14
0.38 - 0.45 0.25 - 0.33 0.14 - 0.21 0.28 - 0.39 0.47 - 0.62 0.82 - 1.02 0.99 - 1.29
40-59 578 6.57 0.67 0.44 0.12 0.26 0.49 0.82 1.56 1.94
0.59 - 0.74 0.39 - 0.50 <LOD - 0.15 0.22 - 0.30 0.43 - 0.56 0.71 - 0.92 1.33 - 1.78 1.52 - 2.36
60-79 541 2.22 0.81 0.57 0.20 0.34 0.59 1.04 1.64 2.32
0.69 - 0.93 0.50 - 0.65 0.15 - 0.24 0.29 - 0.38 0.53 - 0.65 0.87 - 1.20 1.36 - 1.92 1.77 - 2.87
Females
Total,
age 6-79
2830 11.06 0.56 0.34 <LOD 0.19 0.36 0.66 1.16 1.71
0.52 - 0.59 0.30 - 0.37 0.16 - 0.21 0.33 - 0.39 0.60 - 0.73 1.00 - 1.32 1.54 - 1.88
6-11 510 16.47 0.32 0.22 <LOD 0.12 0.25 0.42 0.56 0.73
0.24 - 0.40 0.18 - 0.26 <LOD - 0.16 0.21 - 0.29 0.36 - 0.48 0.44 - 0.68 0.57 - 0.88
12-19 478 12.97 0.39 0.28 <LOD 0.17 0.34 0.52 0.73 0.98
0.33 - 0.46 0.23 - 0.33 0.12 - 0.21 0.29 - 0.39 0.42 - 0.62 0.60 - 0.86 0.68 - 1.27
20-39 655 14.20 0.44 0.27 <LOD 0.16 0.29 0.53 0.91 1.32
0.37 - 0.51 0.24 - 0.32 0.13 - 0.19 0.23 - 0.36 0.44 - 0.62 0.71 - 1.12 0.90 - 1.74
40-59 645 8.06 0.67 0.41 0.10 0.23 0.41 0.79 1.48 2.33
0.62 - 0.72 0.35 - 0.46 <LOD - 0.15 0.18 - 0.27 0.34 - 0.49 0.71 - 0.87 1.33 - 1.63 1.86 - 2.80
60-79 542 4.06 0.73 0.45 0.12 0.23 0.46 0.90 1.56 2.21
0.63 - 0.84 0.38 - 0.52 0.09 - 0.15 0.18 - 0.28 0.40 - 0.52 0.73 - 1.07 1.22 - 1.90 1.80 - 2.61
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.3c
Cadmium (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5478 9.73 0.57 0.42 0.17 0.25 0.39 0.69 1.15 1.60
0.54 - 0.60 0.40 - 0.44 <LOD - 0.18 0.24 - 0.27 0.37 - 0.41 0.63 - 0.75 1.06 - 1.24 1.47 - 1.73
6-11 1030 14.76 0.42 0.34 <LOD 0.24 0.34 0.47 0.70 0.86
0.33 - 0.51 0.31 - 0.38 0.22 - 0.27 0.30 - 0.37 0.41 - 0.53 0.58 - 0.82 0.71 - 1.01
12-19 982 10.49 0.28 0.24 <LOD 0.17 0.24 0.32 0.42 0.53
0.24 - 0.31 0.22 - 0.26 0.15 - 0.19 0.22 - 0.26 0.29 - 0.34 0.35 - 0.49 0.41 - 0.66
20-39 1165 13.22 0.38 0.31 <LOD 0.21 0.30 0.46 0.69 0.83
0.35 - 0.42 0.30 - 0.33 0.19 - 0.23 0.28 - 0.32 0.43 - 0.49 0.62 - 0.77 0.68 - 0.97
40-59 1218 7.39 0.71 0.54 0.22 0.34 0.52 0.86 1.42 1.94
0.67 - 0.74 0.51 - 0.58 <LOD - 0.26 0.31 - 0.36 0.47 - 0.56 0.78 - 0.95 1.24 - 1.59 1.67 - 2.21
60-79 1083 3.14 0.88 0.70 0.31 0.43 0.69 1.11 1.64 2.18
0.80 - 0.96 0.64 - 0.77 0.28 - 0.33 0.39 - 0.47 0.62 - 0.76 0.98 - 1.25 1.52 - 1.75 1.87 - 2.49
Males 
Total,
age 6-79
2652 8.30 0.46 0.36 0.16 0.22 0.34 0.54 0.93 1.22
0.42 - 0.49 0.34 - 0.38 <LOD - 0.17 0.21 - 0.24 0.32 - 0.36 0.49 - 0.60 0.79 - 1.06 1.09 - 1.34
6-11 521 13.05 0.40 0.34 <LOD 0.25 0.34 0.46 0.71 0.83
0.36 - 0.45 0.32 - 0.37 0.23 - 0.27 0.31 - 0.36 0.41 - 0.51 0.57 - 0.85 0.68 - 0.97
12-19 504 8.13 0.27 0.23 0.13 0.16 0.23 0.31 0.43 0.53
0.23 - 0.30 0.21 - 0.25 <LOD - 0.14 0.14 - 0.18 0.21 - 0.25 0.27 - 0.36 0.36 - 0.50 0.31 - 0.75
20-39 512 11.91 0.30 0.26 <LOD 0.18 0.26 0.37 0.53 0.65
0.28 - 0.32 0.25 - 0.28 0.17 - 0.19 0.23 - 0.28 0.34 - 0.41 0.46 - 0.60 0.53 - 0.77
40-59 574 6.62 0.54 0.43 0.18 0.29 0.42 0.70 1.04 1.24
0.49 - 0.59 0.40 - 0.48 <LOD - 0.21 0.24 - 0.33 0.38 - 0.47 0.59 - 0.80 0.90 - 1.17 0.99 - 1.50
60-79 541 2.22 0.75 0.60 0.27 0.39 0.56 1.00 1.47 1.76
0.63 - 0.86 0.52 - 0.69 0.24 - 0.29 0.34 - 0.43 0.48 - 0.65 0.74 - 1.27 1.25 - 1.70 1.48 - 2.04
Females
Total,
age 6-79
2826 11.08 0.68 0.50 <LOD 0.29 0.46 0.80 1.42 2.02
0.63 - 0.72 0.47 - 0.53 0.27 - 0.31 0.42 - 0.51 0.74 - 0.86 1.23 - 1.61 1.77 - 2.27
6-11 509 16.50 0.45 0.34 <LOD 0.24 0.33 0.47 0.70 0.91
0.30 - 0.59 0.29 - 0.40 <LOD - 0.27 0.29 - 0.38 0.39 - 0.56 0.56 - 0.83 0.68 - 1.13
12-19 478 12.97 0.29 0.25 <LOD 0.19 0.25 0.32 0.42 0.53
0.24 - 0.33 0.22 - 0.27 0.17 - 0.21 0.24 - 0.27 0.29 - 0.34 0.34 - 0.50 0.39 - 0.68
20-39 653 14.24 0.47 0.37 <LOD 0.25 0.35 0.55 0.79 1.11
0.40 - 0.53 0.34 - 0.41 0.22 - 0.28 0.31 - 0.38 0.49 - 0.61 0.65 - 0.93 0.81 - 1.41
40-59 644 8.07 0.87 0.67 0.28 0.40 0.66 1.11 1.87 2.29
0.82 - 0.92 0.64 - 0.71 <LOD - 0.33 0.37 - 0.44 0.60 - 0.72 1.00 - 1.23 1.59 - 2.14 2.10 - 2.47
60-79 542 4.06 1.00 0.81 0.36 0.52 0.80 1.23 1.88 2.43
0.91 - 1.10 0.75 - 0.88 0.32 - 0.40 0.47 - 0.57 0.71 - 0.89 1.03 - 1.44 1.63 - 2.14 2.08 - 2.78
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.4 Copper (CASRN 7440-50-8)

Copper (Cu) is the twenty-sixth most abundant element in the Earth's crust and occurs naturally in rock, soil, sediment, water, plants, and animals (CCME, 1997). Pure copper is a reddish, lustrous, malleable, and ductile metal, while many copper compounds have a blue-green colour (CCME, 1997). Copper is commonly found in the form of various sulphide minerals. It is considered an essential element required for the maintenance of health. Copper is needed for many physiological processes, including cellular respiration, iron metabolism, antioxidant defence, connective tissue development, and neurotransmitter production (WHO, 1998).

Copper is released from natural sources, including volcanoes, decaying vegetation, and forest fires, or from anthropogenic sources, such as mining, farming, manufacturing operations, and combustion of fuels and other materials containing copper. Copper is mined extensively for use in the manufacture of brass, bronze, gunmetal, and Monel metal alloys. Copper alloys are used in sheet metal, piping, and electrical conductors, with electrical wire and other electronic applications accounting for 65% of global copper use. Copper and copper alloys are also used in cooking utensils, coins, antifouling paint, dental amalgams, plumbing fixtures and pipes, and architecturalapplications such as roofing, guttering, and flashing. In addition, copper compounds are important chemicals in the textile, petroleum refining, wood preservative, and agricultural industries (CCME, 1997; ATSDR, 2004; WHO, 1998; Health Canada, 2007).

For the general population, most exposure to copper originates from food (CCME, 1997), although additional exposure may result from inhalation of dust particles, from ingestion of drinking water that contains copper, or by hand-to-mouth activity after skin contact with soil, water, and other copper-containing substances. Copper is an essential nutrient for humans and functions mainly as a catalytic co-factor for enzymes, and therefore a certain amount is required for growth and proper functioning of physiological processes. The estimated average requirement (EAR) for copper ranges from 260 μg/day for young children to 1000 μg/day during lactation, and the recommended dietary allowance (RDA) ranges from 340 μg/day for young children to 1300 μg/day during lactation; the adequate intake (AI) for infants (0-12 months) ranges from 200 to 220 µg/day (Health Canada, 2005; IOM, 2001). Overt copper deficiency is relatively rare, but has been associated with effects such as anaemia, neutropenia, and bone abnormalities (WHO, 1998).

Approximately 24-60% of copper is absorbed following oral ingestion; absorption is affected by a number of factors, including the amount of copper in thediet, presence of other metals such as zinc, iron, molybdenum, lead, and cadmium, and age (ATSDR, 2004; WHO, 1998). Following ingestion, absorbed copper is bound to plasma protein carriers such as ceruloplasmin and is transported to the liver. Copper is then re-distributed from the liver to other tissues, where it is stored bound to metallothionein and amino acids (ATSDR, 2004). Bile is the major excretory route for copper; up to 70% of orally ingested copper may be excreted in the feces. Normally 0.5-3.0% of daily copper intake is excreted in the urine (ATSDR, 2004). Exposure to copper can lead to increased copper concentrations in whole blood, serum, urine, hair and the liver. Copper concentrations in serum have been observed to decrease rapidly after exposure, indicating that they may only reflect recent exposures. Copper concentrations in hair and fingernails/toenails have also been used to evaluate exposure, and may reflect exposure over longer periods of time (ATSDR, 2004).

High doses of copper may result in adverse effects, although toxic effects from copper are rare in the general population. Hemodialysis patients, individuals with the genetic disorder Wilson's disease, and those with chronic liver disease may be more susceptible to copper toxicity (WHO, 1998). Acute oral exposure to high doses of copper has been associated with nausea, vomiting, and diarrhea. When inhaled, copper is a respiratory tract irritant. Metal fume fever has been associated with exposure to high concentrations of metal fumes, including copper, generally in an industrial setting. Eye irritation from exposure tocopper dust has also been reported (ATSDR, 2004; WHO, 1998). The International Agency for Research on Cancer (IARC) has not reviewed copper for its carcinogenic potential; the US Environmental Protection Agency (US EPA, 1988) concluded that there were o human data and inadequate animal data to assess the carcinogenicity of copper and copper compounds.

Health Canada (2006) has adopted tolerable Upper Intake Levels (UL) for copper that are based on liver damage as the critical adverse effect. The ULs for copper are 1 mg/day for children 1 to 3 years old, 3 mg/day for children 4 to 8 years old, 5 mg/day for children 9 to 13 years old, 8 mg/day for adolescents (14-18 years old), and 10 mg/day for adults (IOM, 2001). Health Canada (1992) has established an aesthetic objective for drinking water of ≤1 mg/L based on palatability and staining of laundry and plumbing fixtures; this guideline was also deemed protectiveof adverse health effects.

In a study carried out in British Columbia, 61 non-smoking participants aged 30-65 were assessed for the levels of various trace elements in blood and urine. The geometric mean and 95th percentile values of copper in urine were 10.67 µg/g creatinine and 19.66 µg/g creatinine, respectively (Clark et al., 2007).

Copper was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L in blood and as both µg/L and µg/g creatinine in urine (Tables 8.1.4a, 8.1.4b, 8.1.4c). Finding a measurable amount of copper in blood or urine is an indicator of exposure to copper and does not necessarily meanthat an adverse health effect will occur. Because copper is an essential nutrient for the maintenance of health its presence is expected. These data provide reference ranges for blood and urinary levels of copper in the Canadian population.

Table 8.1.4a
Copper - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5318 0.00 927.91 912.76 747.93 812.91 887.56 994.68 1138.95 1256.11
912.55 - 943.28 898.08 - 927.68 736.30 - 759.57 797.98 - 827.84 870.76 - 904.35 975.29 - 1014.08 1119.15 - 1158.74 1225.82 - 1286.41
6-11 909 0.00 981.59 972.64 824.63 892.74 971.55 1050.89 1139.73 1197.71
959.10 - 1004.07 950.95 - 994.82 789.91 - 859.36 864.92 - 920.57 959.29 - 983.82 1025.79 - 1075.99 1092.73 - 1186.72 1149.07 - 1246.36
12-19 945 0.00 914.10 894.17 724.29 780.04 855.45 968.19 1169.56 1374.50
887.04 - 941.17 871.18 - 917.76 701.74 - 746.85 761.94 - 798.14 843.30 - 867.61 925.76 - 1010.62 1088.16 - 1250.96 1179.28 - 1569.72
20-39 1165 0.00 939.88 917.24 732.21 792.57 868.89 999.12 1238.05 1417.19
921.60 - 958.17 900.63 - 934.16 715.69 - 748.72 773.59 - 811.55 845.35 - 892.43 965.91 - 1032.33 1195.39 - 1280.71 1336.55 - 1497.83
40-59 1220 0.00 912.09 902.34 757.61 817.21 882.49 981.04 1080.33 1166.46
894.92 - 929.27 885.60 - 919.39 738.65 - 776.56 793.62 - 840.81 866.34 - 898.63 958.60 - 1003.48 1052.20 - 1108.46 1131.25 - 1201.67
60-79 1079 0.00 926.19 915.59 769.50 829.39 901.40 996.42 1101.17 1182.98
906.71 - 945.67 897.32 - 934.23 748.33 - 790.68 811.53 - 847.25 881.65 - 921.15 971.09 - 1021.75 1055.32 - 1147.02 1118.82 - 1247.14
Males 
Total,
age 6-79
2575 0.00 856.94 849.49 722.24 779.36 844.39 909.55 1007.64 1059.89
840.12 - 873.76 833.41 - 865.87 707.97 - 736.52 767.52 - 791.20 830.58 - 858.19 889.73 - 929.37 975.77 - 1039.51 1023.34 - 1096.44
6-11 458 0.00 1002.59 994.49 843.62 921.11 987.64 1059.46 1154.93 1220.83
979.22 - 1025.97 972.69 - 1016.79 820.25 - 866.98 907.96 - 934.26 972.54 - 1002.74 1028.63 - 1090.29 1093.78 - 1216.08 1143.37 - 1298.29
12-19 489 0.00 841.19 833.49 700.69 761.33 824.91 892.17 1003.67 1083.43
822.65 - 859.73 815.88 - 851.47 677.03 - 724.34 740.76 - 781.89 803.99 - 845.84 866.51 - 917.82 951.26 - 1056.07 1020.94 - 1145.91
20-39 514 0.00 827.54 821.64 704.68 755.78 816.43 879.94 946.30 1016.39
806.19 - 848.89 801.92 - 841.84 682.87 - 726.50 741.65 - 769.92 795.78 - 837.09 855.47 - 904.41 893.05 - 999.56 942.92 - 1089.87
40-59 577 0.00 855.07 848.90 732.66 781.18 849.63 898.92 986.31 1029.77
837.59 - 872.56 831.63 - 866.53 705.98 - 759.33 766.77 - 795.58 835.66 - 863.61 877.06 - 920.78 941.64 - 1030.97 1003.02 - 1056.53
60-79 537 0.00 869.67 862.59 737.75 796.64 863.66 918.74 997.32 1056.03
849.62 - 889.71 843.65 - 881.95 722.61 - 752.89 778.11 - 815.18 841.63 - 885.69 895.70 - 941.79 952.40 - 1042.24 998.36 - 1113.70
Females
Total,
age 6-79
2743 0.00 999.38 981.24 795.67 860.53 954.60 1071.92 1245.00 1396.58
983.35 - 1015.41 966.43 - 996.27 774.63 - 816.70 846.58 - 874.49 941.08 - 968.11 1051.51 - 1092.33 1219.78 - 1270.21 1321.55 - 1471.62
6-11 451 0.00 959.34 950.01 789.13 867.92 955.36 1024.10 1123.17 1189.36
934.22 - 984.46 924.85 - 975.86 745.66 - 832.60 832.86 - 902.97 934.75 - 975.98 990.48 - 1057.73 1076.96 - 1169.38 1145.93 - 1232.78
12-19 456 0.00 994.17 965.89 757.13 813.55 918.91 1102.16 1376.63 1552.75
948.01 - 1040.32 926.76 - 1006.67 740.77 - 773.49 774.49 - 852.60 886.81 - 951.00 999.60 - 1204.72 1177.55 - 1575.72 1395.75 - 1709.75
20-39 651 0.00 1056.06 1027.82 796.60 860.77 981.17 1196.40 1419.10 1575.72
1032.68 - 1079.44 1006.59 - 1049.51 754.42 - 838.77 835.34 - 886.21 959.00 - 1003.35 1145.98 - 1246.82 1337.39 - 1500.81 1457.55 - 1693.88
40-59 643 0.00 968.72 958.75 801.61 868.91 951.29 1042.72 1152.34 1222.73
949.06 - 988.38 939.80 - 978.07 766.86 - 836.37 849.43 - 888.40 931.45 - 971.13 1011.11 - 1074.33 1110.20 - 1194.47 1166.99 - 1278.47
60-79 542 0.00 977.94 966.97 819.51 871.75 952.53 1041.69 1144.88 1251.24
956.44 - 999.44 947.32 - 987.02 802.07 - 836.96 851.57 - 891.93 934.36 - 970.69 1018.34 - 1065.03 1077.90 - 1211.87 1190.79 - 1311.70
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.4b
Copper - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 0.29 11.89 8.98 3.04 5.64 9.99 15.51 21.51 26.67
11.28 - 12.50 8.24 - 9.79 2.48 - 3.60 4.87 - 6.42 9.29 - 10.69 14.61 - 16.40 19.92 - 23.10 25.10 - 28.24
6-11 1034 0.29 13.86 10.48 3.77 7.06 11.92 17.44 23.07 27.48
12.35 - 15.37 9.37 - 11.72 2.93 - 4.62 5.83 - 8.30 10.67 - 13.17 16.18 - 18.70 19.86 - 26.28 25.39 - 29.57
12-19 983 0.31 15.90 12.17 4.38 8.65 13.78 19.50 27.67 32.47
15.04 - 16.75 10.93 - 13.55 3.13 - 5.64 6.95 - 10.36 12.77 - 14.79 18.19 - 20.81 25.17 - 30.17 30.00 - 34.95
20-39 1169 0.43 11.45 8.60 3.01 5.54 9.45 15.20 20.78 25.64
10.55 - 12.36 7.57 - 9.78 2.25 - 3.76 4.53 - 6.56 8.33 - 10.56 14.16 - 16.23 19.23 - 22.32 23.03 - 28.25
40-59 1223 0.41 10.82 8.16 2.68 4.85 9.17 14.49 20.26 24.44
10.01 - 11.63 7.42 - 8.97 2.17 - 3.19 3.93 - 5.76 8.40 - 9.93 13.43 - 15.55 18.82 - 21.71 22.33 - 26.54
60-79 1083 0.00 11.34 9.00 3.48 5.68 9.80 14.29 20.27 24.37
10.59 - 12.08 8.39 - 9.66 2.87 - 4.08 5.00 - 6.37 9.11 - 10.50 13.50 - 15.09 18.08 - 22.45 21.35 - 27.38
Males 
Total,
age 6-79
2662 0.23 12.75 10.07 3.84 6.90 11.37 16.46 22.58 27.12
11.98 - 13.53 9.31 - 10.91 3.15 - 4.52 6.15 - 7.64 10.73 - 12.01 15.37 - 17.54 20.75 - 24.40 25.65 - 28.59
6-11 524 0.00 13.67 10.71 3.89 7.20 12.18 17.47 23.86 27.14
11.23 - 16.11 8.85 - 12.97 2.49 - 5.30 5.45 - 8.94 10.12 - 14.23 15.64 - 19.30 19.76 - 27.95 25.35 - 28.93
12-19 505 0.40 14.45 11.80 4.77 9.09 13.53 17.85 25.21 28.74
13.14 - 15.76 10.25 - 13.60 3.34 - 6.19 7.44 - 10.74 12.46 - 14.60 16.11 - 19.59 22.69 - 27.72 25.98 - 31.49
20-39 514 0.19 12.09 9.46 3.33 6.48 10.36 16.52 21.76 26.33
10.91 - 13.27 8.20 - 10.92 1.69 - 4.98 5.17 - 7.80 8.95 - 11.77 15.03 - 18.01 19.32 - 24.21 23.42 - 29.24
40-59 578 0.52 12.42 9.63 3.62 6.29 11.41 15.93 22.35 27.22
11.11 - 13.74 8.63 - 10.74 2.95 - 4.28 5.45 - 7.13 10.26 - 12.56 14.11 - 17.74 18.82 - 25.88 23.12 - 31.32
60-79 541 0.00 13.05 10.82 4.78 7.74 11.25 15.96 22.08 27.54
11.97 - 14.14 9.94 - 11.77 4.18 - 5.38 7.01 - 8.46 10.17 - 12.33 14.08 - 17.85 19.41 - 24.76 23.50 - 31.59
Females
Total,
age 6-79
2830 0.35 11.03 8.01 2.78 4.79 8.84 14.31 20.62 25.43
10.34 - 11.72 7.26 - 8.84 2.39 - 3.17 4.11 - 5.47 7.97 - 9.72 13.51 - 15.11 19.32 - 21.92 23.18 - 27.67
6-11 510 0.59 14.07 10.23 3.59 6.81 11.69 17.43 22.64 28.06
12.66 - 15.47 9.39 - 11.14 2.77 - 4.40 5.60 - 8.02 10.65 - 12.73 16.12 - 18.73 20.38 - 24.90 23.75 - 32.38
12-19 478 0.21 17.48 12.58 3.81 7.95 15.03 22.44 30.86 34.46
15.05 - 19.90 10.87 - 14.56 2.16 - 5.46 5.41 - 10.49 13.19 - 16.87 19.72 - 25.15 28.56 - 33.16 30.26 - 38.67
20-39 655 0.61 10.81 7.82 2.92 5.08 8.60 13.73 19.46 23.89
9.79 - 11.84 6.86 - 8.91 2.45 - 3.39 4.36 - 5.79 7.16 - 10.04 12.62 - 14.85 17.98 - 20.93 20.17 - 27.60
40-59 645 0.31 9.23 6.93 2.30 3.92 7.60 12.61 19.07 21.87
8.33 - 10.14 6.12 - 7.85 1.77 - 2.84 2.91 - 4.93 6.33 - 8.87 11.27 - 13.95 17.22 - 20.91 18.50 - 25.24
60-79 542 0.00 9.76 7.61 2.87 4.54 8.08 12.53 16.92 23.03
8.85 - 10.67 6.80 - 8.51 2.35 - 3.39 3.88 - 5.20 6.70 - 9.46 11.54 - 13.53 15.34 - 18.50 20.36 - 25.70
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.4c
Copper (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 0.29 12.44 10.86 7.38 8.69 10.62 13.04 16.85 20.42
11.60 - 13.27 10.46 - 11.28 7.08 - 7.68 8.43 - 8.95 10.36 - 10.88 12.65 - 13.43 16.34 - 17.36 19.50 - 21.33
6-11 1031 0.29 20.03 16.09 11.61 13.41 15.75 18.85 22.32 26.92
11.16 - 28.89 15.23 - 17.01 11.00 - 12.21 12.80 - 14.02 15.05 - 16.45 17.87 - 19.83 20.17 - 24.47 23.68 - 30.16
12-19 982 0.31 12.17 10.60 7.41 8.54 10.11 12.42 15.84 20.03
10.78 - 13.55 10.20 - 11.01 7.01 - 7.81 8.25 - 8.82 9.62 - 10.61 11.83 - 13.00 14.95 - 16.73 17.46 - 22.59
20-39 1165 0.43 11.02 9.60 6.70 7.93 9.52 11.31 13.78 15.68
10.14 - 11.89 9.12 - 10.11 6.35 - 7.05 7.64 - 8.23 9.12 - 9.93 10.84 - 11.77 13.03 - 14.54 14.25 - 17.11
40-59 1218 0.41 11.56 10.46 7.45 8.75 10.42 12.32 14.78 17.43
10.46 - 12.66 9.92 - 11.04 7.09 - 7.80 8.33 - 9.16 9.93 - 10.91 11.87 - 12.78 13.88 - 15.67 16.58 - 18.29
60-79 1083 0.00 13.69 12.59 8.67 10.15 12.13 14.76 19.36 22.46
13.15 - 14.22 12.22 - 12.97 8.10 - 9.25 9.83 - 10.46 11.61 - 12.64 14.05 - 15.48 18.09 - 20.64 19.15 - 25.77
Males 
Total,
age 6-79
2653 0.23 11.41 9.95 6.92 7.95 9.58 11.83 15.34 18.49
10.04 - 12.78 9.50 - 10.42 6.64 - 7.19 7.69 - 8.21 9.26 - 9.91 11.44 - 12.23 14.47 - 16.22 17.67 - 19.31
6-11 522 0.00 21.84 16.23 11.69 13.13 15.61 18.58 22.67 27.34
4.55 - 39.13 15.34 - 17.16 11.24 - 12.15 12.20 - 14.05 15.05 - 16.17 17.49 - 19.67 18.96 - 26.38 22.86 - 31.82
12-19 504 0.40 10.70 9.95 7.20 8.21 9.61 12.18 15.24 17.91
10.06 - 11.33 9.31 - 10.65 6.79 - 7.62 7.84 - 8.58 9.11 - 10.11 11.28 - 13.07 13.58 - 16.90 15.81 - 20.01
20-39 512 0.20 9.41 8.67 6.41 7.29 8.51 10.19 11.77 13.23
8.46 - 10.36 8.15 - 9.22 6.11 - 6.71 6.82 - 7.77 7.98 - 9.05 9.61 - 10.76 10.66 - 12.87 11.99 - 14.47
40-59 574 0.52 10.64 9.49 7.09 7.98 9.47 11.19 13.18 16.47
8.77 - 12.50 8.83 - 10.20 6.76 - 7.42 7.62 - 8.33 9.01 - 9.92 10.80 - 11.59 12.10 - 14.26 13.72 - 19.21
60-79 541 0.00 12.56 11.41 7.74 9.21 10.94 13.37 17.00 20.48
11.51 - 13.61 10.78 - 12.07 7.19 - 8.29 8.70 - 9.71 10.26 - 11.61 12.59 - 14.15 15.10 - 18.89 17.03 - 23.94
Females
Total,
age 6-79
2826 0.35 13.46 11.86 8.19 9.68 11.49 14.01 17.95 21.80
12.71 - 14.21 11.42 - 12.31 7.72 - 8.65 9.36 - 9.99 11.18 - 11.81 13.53 - 14.49 17.05 - 18.86 20.32 - 23.28
6-11 509 0.59 18.12 15.95 11.35 13.52 16.08 19.11 22.32 25.20
16.18 - 20.05 14.73 - 17.28 10.11 - 12.59 12.94 - 14.10 15.14 - 17.01 18.19 - 20.04 20.79 - 23.85 21.98 - 28.41
12-19 478 0.21 13.77 11.35 7.73 9.00 10.57 12.63 16.76 25.20
10.60 - 16.94 10.82 - 11.90 7.17 - 8.28 8.31 - 9.70 9.95 - 11.20 12.02 - 13.24 13.63 - 19.88 17.43 - 32.98
20-39 653 0.61 12.64 10.64 7.75 9.00 10.72 12.33 15.30 18.60
10.74 - 14.54 9.99 - 11.34 7.31 - 8.20 8.59 - 9.40 10.19 - 11.25 11.82 - 12.85 14.31 - 16.28 14.57 - 22.63
40-59 644 0.31 12.47 11.53 8.22 9.75 11.37 13.24 16.01 19.94
11.70 - 13.24 10.98 - 12.10 7.46 - 8.97 9.30 - 10.20 10.79 - 11.94 12.69 - 13.79 14.12 - 17.90 16.21 - 23.67
60-79 542 0.00 14.72 13.78 9.96 11.35 13.08 16.06 20.38 24.45
14.16 - 15.28 13.25 - 14.34 9.21 - 10.71 10.99 - 11.71 12.43 - 13.72 14.92 - 17.21 18.98 - 21.78 20.87 - 28.03
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.5 Lead (CASRN 7439-92-1)

Lead (Pb) is a naturally occurring element found in rock and soil. It is a heavy metal and can exist in various oxidation states and in both inorganic and organic forms. Inorganic lead includes substances such as elemental lead, lead sulphate, lead carbonates and oxycarbonates, lead oxides, and lead halides. Organic lead compounds include tetra-, tri-, and dialkyl lead compounds.

Lead is currently used in the refining and manufacturing of products such as lead acid car batteries, lead shot and fishing weights, sheet lead, solder, some brass and bronze products, pipes, artists' paints (other than paints for use by children), and some ceramic glazes. Other uses of lead include dyes in paints and pigments, medical equipment (e.g., radiation shields), scientific equipment, and military equipment (ATSDR, 2007; WHO, 2000).

Lead enters the environment from a variety of natural and human sources. Natural processes, such as soil weathering, erosion, and volcanic activity, release lead, but these processes rarely result in elevated concentrations in the environment, with the exceptionof areas with naturally enriched soils. However, human industrial activities release more lead and frequently result in sites of local contamination. Lead released from industrial emissions into the atmosphere can be a major source of environmental contamination, especially near "point sources" such as smelters or refineries. Historical use of leaded motor fuels also resulted in the ubiquitous distribution of lead throughout the environment (WHO, 2000).

Everyone is exposed to trace amounts of lead through soil, household dust, food, drinking water, and air due to lead's natural abundance in the environment and its widespread use for much of the twentieth century. Lead exposure in Canada has decreased substantially since the early 1970s, mainly because leaded gasoline and lead-based paints were phased out and the use of lead solder in food cans was virtually eliminated (Health Canada, 2008). Current potential sources of lead exposure include ingestion of chips and dust from lead-based paints on interior and exterior surfaces of older buildings; ingestion of water from drinking water distribution systems containing lead pipes, lead plumbing fittings, or lead-based solder; ingestion of food grown in areas with high levels of lead in air, water, or soil, (e.g., near base metal smelters, combustion sources, roads, or in cities); and mouthing of toys or other consumer products containing lead or coated with lead-based paints or glazes (Health Canada, 2007).

While only about 10% of the lead ingested by adults is absorbed from the intestine into the blood, about 40% of ingested lead is absorbed by the bodies of preschool children (Health Canada, 2002). Once absorbed by the human body, lead circulates in the bloodstream and either accumulates in tissues (especially in bone) or is excreted from the body as waste. Some lead may also be absorbed into soft tissues such as the liver, kidneys, pancreas, and lungs. Whereas approximately 70% of the total body burden of lead is located in the bones of children, more than 90% of the total body burden of lead is found in the bones in human adults (US EPA, 2006). Blood and soft tissues represent the active pool for lead, while bone acts as a storage pool; thus, bone lead is considered a biomarker of long-term exposure (ATSDR, 2007). Bone lead can be re-mobilized into the circulating pool of lead, particularly during physiological states of stress associated with increased bone resorption, such as pregnancy, lactation, menopause, extended bed rest, hyperparathyroidism, and osteoporosis (Health Canada, 2002; Rothenberg et al., 2000). In pregnant women, lead stored in bone can act as a source of fetal lead exposure (Rothenberg et al., 2000). Lead is also present in breast milk and can be transferred from lactating mothers to infants (ATSDR, 2007; US EPA, 2006). Blood lead concentrations decrease slowly after exposure, with ahalf-life of about two to six weeks (Health Canada, 1992). The half-life for lead accumulated in the body, such as in bone, is around 25 to 30 years (Health Canada, 2007; ATSDR, 2007). Blood lead is thepreferred method of evaluating human exposure to lead, although other matrices such as urine, bone, hair, and teeth have also been used (CDC, 2005; ATSDR, 2007).

Due to the ability of lead to persist in the body, it is considered a cumulative general poison, with infants, toddlers, children, fetuses, and pregnant women being most susceptible to adverse health effects (US EPA, 2006; Health Canada, 2007). Following acute high-level exposure, lead interferes with a variety of metabolic processes and can cause vomiting, diarrhea, convulsion, coma, and death, although severe cases of lead poisoning are rarely reported in Canada (Health Canada, 2007). Symptoms of long-term exposure to lower lead levels are less evident. Chronic low-level exposure may affect both the central and peripheral nervous systems (ATSDR, 2007). Lead has also been associated with effects on the cardiovascular system (e.g., blood pressure), kidneys, blood, and the immune system (ATSDR, 2007). Cognitive and neurobehavioral effects have been recognized as major concerns for children exposed to lead. Recently, a pooled analysis of several epidemiological studies suggested that deficits in IQ may be associated with elevated blood lead levels (ATSDR 2007). There is no known threshold for the effects of lead exposure on cognitive function and neurobehavioural development (US EPA, 2006; CDC, 2002). The International Agency for Research on Cancer (IARC) classifies inorganic lead compounds as probable human carcinogens (Group 2A) (IARC, 2004).

Lead is listed on Schedule 1 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the primary federal legislation that deals with industrial chemicals, and this allows the federal government to control the importation, manufacture, distribution, and use of lead and lead compounds in Canada (Health Canada, 2007). CEPA 1999 restricts the use of lead in gasoline and controls its release from secondary lead smelters and steel mills. The use of lead in various toys and other consumer products, which represent a potential risk of lead exposure, is restricted under the Hazardous Products Act and its associated regulations (e.g., Hazardous Products [Glazed Ceramics and Glassware] Regulations, Hazardous Products [Toys] Regulations, Surface Coating Materials Regulations) (Health Canada, 2007). The Guideline for Canadian Drinking Water Quality for lead was established as a maximum acceptable concentration of 0.010 mg/L (10 µg/L) (based on a two-year old child as the sensitive sub-group) (Health Canada, 1992).

In 1994, the Federal-Provincial-Territorial Committee on Environmental and Occupational Health recommended a blood lead intervention level of 10 µg/dL. Recent scientific studies indicate that chronic health effects may be occurring in children at blood lead levels below 10 µg/dL (Health Canada, 2007). In recognition of this, Health Canada has undertaken a comprehensive toxicological assessment of the current science on lead and, concurrently, is developing a risk management approach. The new evidence provided in the toxicological assessment will also provide a basis for Health Canada's review of its blood lead intervention levels.

In a study carried out in the region of Québec City on 441 adults aged 18-65, the geometric mean and 90th percentile blood lead concentrations were 2.15 and 4.21 μg/dL, respectively. The geometric and 90th percentile urine lead concentrations were 0.12 and 0.29 µg/dL, respectively (INSPQ, 2004). Higher lead levels have been found in some northern communities; a geometric mean blood level of 3.9 μg/dL was measured from 917 adults aged 18-74 in Nunavik, Québec in 2004 (Dewailly et al., 2007).

Levels of lead in blood and urine were measured in all participants aged 6-79 years in the Canadian Health Measures Survey and presented as μg/dL in blood and as both μg/L and μg/g creatinine in urine (Tables 8.1.5a, 8.1.5b, 8.1.5c). Finding a measurable amount of lead in blood and urine does not necessarily mean that an adverse health effectwill occur. These data provide reference ranges for blood and urinary levels of lead in the Canadian population.

Table 8.1.5a
Lead - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/dL) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 0.02 1.66 1.34 0.60 0.86 1.30 2.03 3.07 3.79
1.52 - 1.79 1.24 - 1.44 0.56 - 0.65 0.79 - 0.93 1.21 - 1.39 1.83 - 2.22 2.77 - 3.37 3.32 - 4.26
6-11 910 0.00 1.02 0.90 0.53 0.65 0.87 1.19 1.61 1.95
0.91 - 1.13 0.81 - 0.99 0.49 - 0.57 0.59 - 0.70 0.77 - 0.97 1.05 - 1.34 1.47 - 1.76 1.65 - 2.26
12-19 945 0.00 0.89 0.80 0.47 0.57 0.76 1.05 1.34 1.64
0.81 - 0.97 0.74 - 0.85 0.44 - 0.51 0.53 - 0.62 0.70 - 0.83 0.99 - 1.11 1.11 - 1.56 1.47 - 1.82
20-39 1165 0.09 1.37 1.12 0.57 0.76 1.05 1.58 2.35 3.12
1.27 - 1.46 1.04 - 1.21 0.52 - 0.62 0.69 - 0.82 0.99 - 1.11 1.39 - 1.77 2.02 - 2.68 2.75 - 3.49
40-59 1220 0.00 1.87 1.60 0.82 1.15 1.55 2.22 3.17 3.87
1.67 - 2.07 1.46 - 1.75 0.70 - 0.95 1.06 - 1.24 1.43 - 1.67 1.95 - 2.50 2.71 - 3.63 3.16 - 4.57
60-79 1079 0.00 2.49 2.08 1.04 1.44 2.07 3.02 4.17 5.19
2.22 - 2.77 1.90 - 2.29 0.93 - 1.14 1.33 - 1.56 1.90 - 2.24 2.68 - 3.37 3.53 - 4.81 4.20 - 6.18
Males 
Total,
age 6-79
2576 0.00 1.86 1.51 0.71 1.01 1.44 2.21 3.26 4.22
1.69 - 2.03 1.40 - 1.63 0.66 - 0.76 0.95 - 1.08 1.34 - 1.54 2.01 - 2.42 2.87 - 3.66 3.71 - 4.72
6-11 459 0.00 1.04 0.92 0.54 0.66 0.89 1.21 1.64 1.96
0.94 - 1.14 0.85 - 0.99 0.50 - 0.58 0.61 - 0.72 0.79 - 1.00 1.10 - 1.31 1.44 - 1.83 1.78 - 2.13
12-19 489 0.00 0.99 0.88 0.51 0.65 0.87 1.16 1.53 1.79
0.88 - 1.11 0.82 - 0.96 0.46 - 0.55 0.60 - 0.69 0.79 - 0.95 1.05 - 1.27 1.29 - 1.77 1.28 - 2.29
20-39 514 0.00 1.70 1.41 0.75 0.97 1.30 2.00 2.94 3.65
1.56 - 1.85 1.28 - 1.55 0.65 - 0.85 0.87 - 1.07 1.15 - 1.46 1.68 - 2.33 2.59 - 3.30 2.88 - 4.42
40-59 577 0.00 2.01 1.74 0.98 1.25 1.61 2.35 3.31 3.95
1.75 - 2.27 1.57 - 1.92 0.89 - 1.08 1.15 - 1.35 1.46 - 1.77 1.92 - 2.77 2.77 - 3.85 3.02 - 4.88
60-79 537 0.00 2.78 2.31 1.20 1.55 2.24 3.27 4.86 6.17
2.46 - 3.10 2.08 - 2.57 1.07 - 1.34 1.37 - 1.73 1.98 - 2.49 2.86 - 3.68 3.96 - 5.75 4.95 - 7.39
Females
Total,
age 6-79
2743 0.04 1.45 1.18 0.55 0.74 1.14 1.74 2.73 3.50
1.30 - 1.60 1.08 - 1.30 0.50 - 0.60 0.68 - 0.81 1.04 - 1.25 1.51 - 1.97 2.35 - 3.12 3.03 - 3.97
6-11 451 0.00 0.99 0.87 0.51 0.64 0.85 1.16 1.61 1.93
0.85 - 1.13 0.77 - 0.99 0.46 - 0.57 0.57 - 0.70 0.73 - 0.97 0.93 - 1.39 1.37 - 1.86 1.26 - 2.60
12-19 456 0.00 0.77 0.71 0.43 0.53 0.68 0.91 1.16 1.46
0.72 - 0.83 0.66 - 0.77 0.37 - 0.49 0.48 - 0.58 0.62 - 0.75 0.79 - 1.04 0.98 - 1.33 1.25 - 1.67
20-39 651 0.15 1.02 0.89 0.52 0.64 0.86 1.19 1.64 2.05
0.92 - 1.12 0.81 - 0.98 0.46 - 0.57 0.60 - 0.68 0.77 - 0.96 1.08 - 1.30 1.38 - 1.91 1.78 - 2.32
40-59 643 0.00 1.72 1.47 0.71 1.05 1.46 2.11 3.11 3.78
1.51 - 1.94 1.31 - 1.65 0.59 - 0.82 0.90 - 1.19 1.27 - 1.64 1.81 - 2.41 2.49 - 3.74 3.05 - 4.52
60-79 542 0.00 2.23 1.89 0.94 1.34 1.93 2.67 3.69 4.53
1.92 - 2.54 1.69 - 2.12 0.81 - 1.07 1.15 - 1.52 1.69 - 2.18 2.27 - 3.06 3.20 - 4.17 3.81 - 5.25
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.5b
Lead - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 7.54 0.76 0.48 0.13 0.28 0.53 0.92 1.56 2.11
0.68 - 0.84 0.43 - 0.54 0.11 - 0.16 0.24 - 0.32 0.47 - 0.58 0.83 - 1.01 1.37 - 1.76 1.83 - 2.40
6-11 1034 9.28 0.55 0.36 <LOD 0.22 0.41 0.65 1.01 1.31
0.50 - 0.60 0.33 - 0.40 <LOD - 0.16 0.18 - 0.26 0.37 - 0.45 0.57 - 0.73 0.89 - 1.13 1.12 - 1.49
12-19 983 10.17 0.60 0.39 <LOD 0.24 0.43 0.74 1.16 1.55
0.52 - 0.68 0.35 - 0.44 0.21 - 0.28 0.41 - 0.46 0.64 - 0.83 1.02 - 1.29 1.27 - 1.82
20-39 1169 9.50 0.64 0.41 0.11 0.24 0.45 0.75 1.32 1.83
0.58 - 0.71 0.35 - 0.47 <LOD - 0.14 0.19 - 0.29 0.39 - 0.51 0.63 - 0.87 1.10 - 1.55 1.59 - 2.07
40-59 1223 5.97 0.84 0.55 0.17 0.32 0.61 1.02 1.67 2.26
0.70 - 0.98 0.47 - 0.63 0.13 - 0.21 0.26 - 0.38 0.56 - 0.67 0.89 - 1.14 1.31 - 2.02 1.69 - 2.84
60-79 1083 3.14 1.01 0.66 0.20 0.37 0.68 1.28 2.12 2.74
0.90 - 1.12 0.60 - 0.73 0.15 - 0.25 0.32 - 0.42 0.62 - 0.74 1.13 - 1.43 1.82 - 2.43 2.10 - 3.37
Males 
Total,
age 6-79
2662 5.86 0.85 0.55 0.15 0.33 0.60 1.02 1.71 2.27
0.75 - 0.94 0.49 - 0.61 0.11 - 0.19 0.30 - 0.36 0.55 - 0.65 0.92 - 1.12 1.47 - 1.94 1.83 - 2.70
6-11 524 6.87 0.53 0.38 0.12 0.23 0.43 0.69 1.02 1.34
0.45 - 0.61 0.32 - 0.46 <LOD - 0.17 0.17 - 0.29 0.33 - 0.53 0.58 - 0.80 0.83 - 1.21 1.06 - 1.63
12-19 505 9.11 0.56 0.38 <LOD 0.25 0.42 0.69 1.02 1.37
0.46 - 0.65 0.33 - 0.44 0.21 - 0.29 0.38 - 0.46 0.60 - 0.79 0.83 - 1.20 0.93 - 1.81
20-39 514 7.00 0.74 0.47 0.11 0.30 0.53 0.95 1.61 1.99
0.63 - 0.84 0.38 - 0.58 <LOD - 0.15 0.22 - 0.38 0.42 - 0.64 0.77 - 1.14 1.31 - 1.91 1.50 - 2.47
40-59 578 4.67 0.95 0.63 0.18 0.38 0.67 1.12 1.73 2.64
0.76 - 1.15 0.55 - 0.72 0.13 - 0.23 0.28 - 0.47 0.61 - 0.73 0.98 - 1.27 1.19 - 2.26 1.79 - 3.50
60-79 541 2.03 1.18 0.84 0.31 0.51 0.84 1.53 2.25 3.07
1.03 - 1.34 0.74 - 0.95 0.23 - 0.38 0.44 - 0.57 0.67 - 1.00 1.28 - 1.78 1.98 - 2.51 2.61 - 3.54
Females
Total,
age 6-79
2830 9.12 0.67 0.43 0.13 0.23 0.45 0.80 1.36 1.86
0.59 - 0.76 0.37 - 0.48 <LOD - 0.15 0.19 - 0.27 0.39 - 0.51 0.69 - 0.91 1.16 - 1.55 1.55 - 2.17
6-11 510 11.76 0.57 0.34 <LOD 0.20 0.40 0.62 0.99 1.29
0.51 - 0.63 0.31 - 0.38 0.16 - 0.25 0.38 - 0.43 0.56 - 0.69 0.84 - 1.14 1.06 - 1.51
12-19 478 11.30 0.65 0.40 <LOD 0.23 0.44 0.79 1.30 1.62
0.51 - 0.79 0.35 - 0.46 <LOD - 0.17 0.18 - 0.28 0.40 - 0.48 0.68 - 0.91 1.02 - 1.58 0.93 - 2.31
20-39 655 11.45 0.55 0.35 <LOD 0.21 0.39 0.65 0.95 1.34
0.46 - 0.63 0.31 - 0.41 <LOD - 0.14 0.16 - 0.26 0.34 - 0.45 0.55 - 0.76 0.78 - 1.12 1.14 - 1.55
40-59 645 7.13 0.73 0.48 0.15 0.25 0.54 0.95 1.53 2.09
0.61 - 0.84 0.40 - 0.57 0.10 - 0.20 0.18 - 0.32 0.42 - 0.65 0.85 - 1.04 1.14 - 1.93 1.62 - 2.56
60-79 542 4.24 0.85 0.54 0.14 0.28 0.57 1.11 1.76 2.28
0.70 - 1.01 0.45 - 0.64 <LOD - 0.20 0.20 - 0.36 0.45 - 0.69 0.88 - 1.34 1.46 - 2.06 1.25 - 3.32
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.5c
Lead (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 7.56 0.81 0.58 0.24 0.36 0.58 0.94 1.49 1.98
0.74 - 0.88 0.53 - 0.64 0.21 - 0.28 0.33 - 0.39 0.52 - 0.63 0.84 - 1.04 1.35 - 1.64 1.75 - 2.22
6-11 1031 9.31 0.76 0.56 <LOD 0.38 0.54 0.81 1.22 1.60
0.66 - 0.86 0.51 - 0.61 <LOD - 0.30 0.34 - 0.42 0.47 - 0.62 0.72 - 0.91 1.08 - 1.36 1.26 - 1.95
12-19 982 10.18 0.47 0.34 <LOD 0.23 0.34 0.51 0.79 1.06
0.39 - 0.55 0.30 - 0.38 0.20 - 0.26 0.31 - 0.37 0.45 - 0.57 0.66 - 0.93 0.74 - 1.39
20-39 1165 9.53 0.65 0.45 0.21 0.30 0.45 0.70 1.01 1.39
0.58 - 0.72 0.41 - 0.50 <LOD - 0.25 0.27 - 0.32 0.42 - 0.49 0.63 - 0.77 0.87 - 1.15 1.07 - 1.70
40-59 1218 5.99 0.88 0.70 0.31 0.45 0.70 1.11 1.61 2.04
0.78 - 0.98 0.63 - 0.78 0.27 - 0.34 0.42 - 0.49 0.62 - 0.78 0.96 - 1.26 1.35 - 1.88 1.66 - 2.42
60-79 1083 3.14 1.23 0.93 0.41 0.61 0.93 1.43 2.12 2.87
1.08 - 1.37 0.84 - 1.03 0.35 - 0.48 0.55 - 0.67 0.81 - 1.06 1.31 - 1.56 1.80 - 2.44 2.38 - 3.35
Males 
Total,
age 6-79
2653 5.88 0.73 0.54 0.23 0.34 0.53 0.87 1.34 1.82
0.66 - 0.80 0.50 - 0.58 0.20 - 0.26 0.32 - 0.37 0.49 - 0.57 0.77 - 0.96 1.18 - 1.49 1.42 - 2.21
6-11 522 6.90 0.76 0.57 0.27 0.39 0.57 0.85 1.24 1.74
0.61 - 0.90 0.53 - 0.63 <LOD - 0.31 0.35 - 0.44 0.48 - 0.66 0.75 - 0.94 1.05 - 1.42 1.31 - 2.16
12-19 504 9.13 0.43 0.32 <LOD 0.21 0.32 0.51 0.74 0.96
0.36 - 0.50 0.29 - 0.36 0.20 - 0.23 0.28 - 0.35 0.44 - 0.58 0.59 - 0.90 0.59 - 1.33
20-39 512 7.03 0.58 0.43 0.21 0.29 0.44 0.67 1.02 1.34
0.52 - 0.63 0.38 - 0.49 <LOD - 0.26 0.26 - 0.32 0.40 - 0.47 0.58 - 0.76 0.81 - 1.23 0.75 - 1.94
40-59 574 4.70 0.78 0.62 0.29 0.40 0.60 0.94 1.34 1.80
0.66 - 0.90 0.55 - 0.69 0.27 - 0.31 0.36 - 0.45 0.53 - 0.68 0.78 - 1.09 1.04 - 1.64 1.10 - 2.49
60-79 541 2.03 1.14 0.88 0.42 0.59 0.87 1.33 1.84 2.36
1.00 - 1.29 0.82 - 0.96 0.39 - 0.44 0.53 - 0.64 0.77 - 0.97 1.13 - 1.53 1.49 - 2.20 1.56 - 3.17
Females
Total,
age 6-79
2826 9.13 0.89 0.63 0.25 0.39 0.63 1.05 1.64 2.10
0.79 - 0.99 0.56 - 0.71 <LOD - 0.29 0.34 - 0.43 0.55 - 0.71 0.89 - 1.21 1.38 - 1.90 1.75 - 2.44
6-11 509 11.79 0.77 0.54 <LOD 0.38 0.53 0.79 1.17 1.52
0.64 - 0.90 0.48 - 0.61 0.34 - 0.42 0.46 - 0.60 0.68 - 0.90 1.00 - 1.35 1.11 - 1.94
12-19 478 11.30 0.51 0.36 <LOD 0.26 0.35 0.53 0.84 1.08
0.39 - 0.63 0.31 - 0.42 <LOD - 0.22 0.21 - 0.30 0.31 - 0.39 0.42 - 0.64 0.65 - 1.02 0.52 - 1.64
20-39 653 11.49 0.72 0.48 <LOD 0.31 0.46 0.73 0.99 1.44
0.56 - 0.88 0.43 - 0.54 <LOD - 0.24 0.26 - 0.35 0.43 - 0.49 0.63 - 0.82 0.81 - 1.17 1.02 - 1.87
40-59 644 7.14 0.98 0.79 0.35 0.51 0.79 1.27 1.82 2.10
0.85 - 1.11 0.69 - 0.91 0.26 - 0.44 0.43 - 0.58 0.69 - 0.89 1.03 - 1.51 1.56 - 2.08 1.43 - 2.78
60-79 542 4.24 1.30 0.97 0.41 0.63 1.00 1.53 2.35 2.99
1.07 - 1.53 0.83 - 1.14 <LOD - 0.56 0.51 - 0.74 0.78 - 1.21 1.35 - 1.72 1.99 - 2.71 2.33 - 3.65
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.6 Manganese (CASRN 7439-96-5)

Manganese (Mn) is a naturally occurring element that comprises approximately 0.1% of the Earth's crust and is considered to be one of the least toxic elements (Health Canada, 1987). Manganese is an essential nutrient required for the maintenance of human health (ATSDR, 2000). Pure manganese is silver in colour, but manganese in the environment is always found combined with other elements to form a variety of minerals. Manganese can exist in both organic and inorganic forms, with inorganic manganese in the Mn(II), Mn(III), or Mn(IV) oxidation states most often encountered in the environment and in the workplace. Organo-manganese compounds do not occur in nature, but are manufactured for specific uses (ATSDR, 2000).

Metallic manganese is used principally in steel production to improve hardness and strength. Other uses of manganese compounds include production of dry-cell batteries, fireworks, matches, animal feed (to supply essential trace minerals), porcelain and glass-bonding materials, and fertilizers. Potassium permanganate is commonly used in water and waste-treatment plants as a disinfectant and anti-algal agent, but is also used for metal cleaning, tanning, and bleaching (ATSDR, 2000).

The predominant use of organo-manganese compounds is in the form of methylcyclopentadienyl manganese tricarbonyl (MMT), an octane enhancer used by national petroleum refiners prior to 2004 (Health Canada, 2010). Other organo-manganese compounds, such as Maneb or Mancozeb, both of which are currently registered for use in Canada, are used as fungicides for fruits and vegetables, and in seed treatment. Another organo-manganese compound, mangafodipir, is used as a contrast agent in magnetic resonance imaging (MRI) (ATSDR, 2000).

Manganese is ubiquitous in the environment and is naturally occurring in air, soil, water, and biological organisms, including food. Manganese is released to the air from iron, steel, and power plants, from coke ovens, and in dust from mining operations. Food is the main source of manganese exposure for the majority of the population (ATSDR, 2000). Manganese is found in trace amounts in all plant and animal tissues. It is estimated that grain products contribute approximately 37% of manganese intake in the adult diet (IOM, 2001). Concentrations in food range from approximately 0.03 mg/kg in milk to approximately 43.9 mg/kg in wheat flour (Health Canada, 2007). The daily dietary intake of manganese for the Canadian population was estimated to be 56 µg/kg body weight/day in the last Canadian Total Diet Study carried out in 2002 (Health Canada, 2009).

The main routes of absorption for manganese are the respiratory and gastrointestinal tracts. Approximately 3-5% of orally ingested manganese is absorbed from the gastrointestinal tract and enters systemic circulation. Conversely, inhaled manganese enters systemic circulation directly, making the manganese available for distribution to and accumulation in the body's tissues, including the brain (Health Canada, 2008). The ubiquitous presence of manganese in foods along with the essential nature of this element has resulted in the development of homeostatic control mechanisms for dietary manganese. Under conditions of high dietary manganese, adaptive changes include reduced gastrointestinal absorption of manganese, enhanced manganese liver metabolism, and increased biliary and pancreatic excretion of manganese (Davis et al., 1993; Malecki et al., 1996; Finley and Davis, 1999; Dorman et al., 2001; Dorman et al., 2002). Biliary excretionis the main excretory pathway, and once manganese reaches the intestines, a large fraction of the element is ultimately excreted in the feces (Davis et al., 1993; Malecki et al., 1996). Urinary excretion of manganese is low and has been found to be relatively resistant to small changes in dietary manganese intake (Davis & Greger, 1992).

Concentrations in blood and urine can be used to evaluate exposure to manganese. Whole blood is preferred rather than plasma or serum since slight hemolysis of samples can have a significant effect on plasma or serum manganese concentrations (IOM, 2001). Concentrations in blood tend to reflect the overall body burden of manganese, while concentrations in urine are more commonly used to measure levels following an acute exposure to manganese as it is only responsive to significant fluctuations in manganese intake (IOM, 2001). The normal range of manganese concentrations is approximately 4 to 14 µg/L in whole blood, 0.15 to 2.65 µg/L in serum, and 0.97 to 1.07 µg/L in urine (ATSDR, 2000).

Manganese is an essential nutrient involved in the formation of bone, in cellular protection from free radical damage, and in amino acid, cholesterol, and carbohydrate metabolism (IOM, 2001; ATSDR, 2000). Health Canada (2005) has adopted Tolerable Upper Intake Levels (UL) developed by the Institute of Medicine (IOM) for manganese, which account for both its essentiality and its potential toxicity. The ULs for manganese are 2 mg/day for children 1-3 years old, 3 mg/day for children 4-8 years old, 6 mg/day for children 9-13 years old, 9 mg/day for adolescents 14-18 years old, and 11 mg/day for adults. The ULs for pregnant and lactating women are 9 mg/day for women 18 years or younger and 11 mg/day for women 19 years or older (IOM, 2001).

Manganese deficiency in humans is rare; however, excessive exposure to manganese can cause neurological effects (ATSDR, 2000). Very high concentrations of manganese in air, such as those associated with occupational exposures, can result in "metal fume fever," pneumonitis, and manganism (a condition resembling Parkinson's disease) (Health Canada, 1987). Exposure to moderately high levels of manganese in air can result in subtle neurological effects such as poorer fine motor skills. Health Canada has established a reference concentration of 0.05 µg/m3 for manganese in air (Health Canada, 2010). Health Canada (1987) has established an aesthetic objective for drinking water of ≤0.05 mg/L based on palatability and staining of laundry and plumbing fixtures; this guideline was also deemed protective of adverse health effects. The World Health Organization (WHO) has established a health-based drinking water guideline for manganese of <0.4 mg/L (WHO, 2006).

The International Agency for Research on Cancer (IARC) has not published an evaluation of the carcinogenicity of manganese. The United States Environmental Protection Agency classifiedmanganese as not classifiable as to human carcinogenicity based on an absence of human data and inadequate animal data (Group D) (US EPA, 1996).

In a study carried out in British Columbia, 61 non-smoking participants aged 30-65 were assessed for the levels of various trace elements in blood and urine. The geometric mean and 95th percentile values of manganese in blood were 10.75 µg/L and 14.94 µg/L, respectively (Clark et al., 2007). In a separate study carried out in the Québec City region, 500 participants aged 18-65 were assessed for the levels of various trace elements in blood and urine. The geometric mean and 90th percentile values of manganese in blood were 9.33 µg/L and 13.74 µg/L, respectively (INSPQ, 2004). In a study of manganese levels in a non-occupationally exposed adult population in Southwest Québec in 1996, blood samples were obtained from 297 subjects between the age of 20 and 69 years (Baldwin et al., 1999). The geometric mean blood manganese level for this population was 7.1 µg/L. A study investigating the link between manganese levels and convulsive disorders measured blood manganese levels in a reference population of 120 children (Dupont & Tanaka, 1985). Twenty-nine children, aged 2 to17 years, were tested in 1976, and 24 children, aged 2 to 17 years, were tested in 1984. The mean blood manganese level for the 1976 reference population was 14.4 µg/L, while the mean for the 1984 reference population was 14.0 µg/L.

Manganese was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L in blood and as both µg/L and µg/g creatinine in urine (Tables 8.1.6a, 8.1.6b, 8.1.6c). Finding a measurable amount of manganese in blood or urine is an indicator of exposure to manganese and does not necessarily mean that an adverse health effect will occur. Because manganese is an essential nutrient for the maintenance of health, its presence is expected. These data provide reference ranges for blood and urinary levels of manganese in the Canadian population.

Table 8.1.6a
Manganese - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5309 0.00 9.68 9.22 6.34 7.49 9.04 11.19 13.71 15.63
9.43 - 9.94 8.99 - 9.47 6.11 - 6.58 7.29 - 7.70 8.81 - 9.27 10.89 - 11.49 13.18 - 14.24 14.98 - 16.27
6-11 907 0.00 10.28 9.86 6.94 8.08 9.74 11.82 14.14 16.36
9.99 - 10.58 9.59 - 10.14 6.67 - 7.20 7.76 - 8.40 9.38 - 10.10 11.43 - 12.21 13.42 - 14.86 15.49 - 17.22
12-19 942 0.00 10.44 9.97 6.68 8.03 9.96 12.20 14.91 16.31
10.13 - 10.75 9.71 - 10.24 6.44 - 6.93 7.75 - 8.30 9.49 - 10.42 11.51 - 12.88 14.32 - 15.51 15.74 - 16.89
20-39 1162 0.00 9.66 9.17 6.27 7.45 9.00 11.22 13.99 16.09
9.28 - 10.04 8.84 - 9.51 6.03 - 6.52 7.14 - 7.75 8.67 - 9.32 10.87 - 11.58 12.91 - 15.06 14.67 - 17.50
40-59 1219 0.00 9.56 9.13 6.42 7.50 8.90 10.83 13.54 15.28
9.15 - 9.97 8.78 - 9.49 6.07 - 6.76 7.22 - 7.79 8.54 - 9.26 10.51 - 11.14 12.81 - 14.27 14.02 - 16.54
60-79 1079 0.00 9.27 8.83 5.96 7.15 8.82 10.82 12.75 14.30
9.01 - 9.54 8.56 - 9.11 5.55 - 6.37 7.00 - 7.29 8.42 - 9.23 10.43 - 11.22 12.14 - 13.36 13.59 - 15.02
Males 
Total,
age 6-79
2572 0.00 9.17 8.77 6.15 7.20 8.66 10.58 12.83 14.20
8.88 - 9.45 8.51 - 9.04 5.83 - 6.48 6.94 - 7.46 8.36 - 8.96 10.18 - 10.97 12.14 - 13.53 13.47 - 14.92
6-11 458 0.00 9.88 9.46 6.59 7.65 9.35 11.63 13.56 15.44
9.40 - 10.36 9.06 - 9.88 6.09 - 7.10 7.22 - 8.09 8.93 - 9.77 11.03 - 12.23 12.08 - 15.05 13.11 - 17.77
12-19 489 0.00 9.81 9.44 6.46 7.77 9.43 11.43 13.57 14.71
9.30 - 10.31 8.99 - 9.90 6.16 - 6.76 7.40 - 8.14 8.91 - 9.94 10.34 - 12.51 12.57 - 14.56 13.89 - 15.54
20-39 511 0.00 8.96 8.60 6.21 7.12 8.42 10.34 12.43 13.45
8.67 - 9.25 8.31 - 8.89 5.90 - 6.51 6.67 - 7.58 8.02 - 8.82 9.78 - 10.90 11.34 - 13.53 12.17 - 14.74
40-59 577 0.00 9.15 8.77 6.27 7.31 8.69 10.38 12.35 13.97
8.71 - 9.59 8.39 - 9.18 5.61 - 6.93 6.86 - 7.77 8.22 - 9.15 9.92 - 10.83 11.29 - 13.41 12.63 - 15.31
60-79 537 0.00 8.87 8.41 5.65 6.79 8.23 10.29 12.50 14.18
8.48 - 9.25 8.06 - 8.78 5.40 - 5.91 6.58 - 7.00 7.75 - 8.72 9.62 - 10.96 11.61 - 13.38 13.36 - 15.00
Females
Total,
age 6-79
2737 0.00 10.21 9.70 6.62 7.80 9.55 11.75 14.75 16.48
9.93 - 10.49 9.44 - 9.96 6.40 - 6.84 7.54 - 8.06 9.22 - 9.88 11.45 - 12.05 13.90 - 15.59 15.48 - 17.48
6-11 449 0.00 10.71 10.31 7.38 8.54 10.16 12.17 14.73 16.43
10.40 - 11.03 10.00 - 10.62 6.91 - 7.84 8.23 - 8.85 9.64 - 10.69 11.60 - 12.73 13.62 - 15.85 15.55 - 17.31
12-19 453 0.00 11.15 10.60 7.17 8.33 10.78 13.22 16.10 17.28
10.84 - 11.45 10.35 - 10.86 6.65 - 7.69 7.99 - 8.67 10.33 - 11.24 12.10 - 14.33 15.45 - 16.75 16.33 - 18.24
20-39 651 0.00 10.38 9.79 6.61 7.79 9.49 11.97 15.80 17.32
9.67 - 11.09 9.20 - 10.42 6.11 - 7.12 7.26 - 8.32 8.84 - 10.14 11.23 - 12.72 13.89 - 17.72 15.24 - 19.40
40-59 642 0.00 9.98 9.50 6.50 7.73 9.21 11.53 14.08 16.23
9.39 - 10.56 9.03 - 10.00 6.13 - 6.87 7.36 - 8.10 8.61 - 9.81 10.92 - 12.13 12.57 - 15.59 13.66 - 18.81
60-79 542 0.00 9.64 9.23 6.59 7.61 9.39 11.03 12.91 14.34
9.40 - 9.89 9.00 - 9.46 6.30 - 6.88 7.36 - 7.86 9.00 - 9.77 10.63 - 11.43 12.27 - 13.55 13.57 - 15.11
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.6b
Manganese - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5431 35.54 0.15 0.08 <LOD <LOD 0.08 0.16 0.29 0.40
0.12 - 0.18 0.07 - 0.09 0.07 - 0.10 0.14 - 0.19 0.24 - 0.35 0.34 - 0.47
6-11 1032 38.08 0.25 0.08 <LOD <LOD 0.08 0.17 0.30 0.45
0.08 - 0.43 0.07 - 0.09 0.07 - 0.09 0.14 - 0.20 0.26 - 0.35 0.36 - 0.54
12-19 981 32.31 0.17 0.09 <LOD <LOD 0.09 0.17 0.29 0.41
0.12 - 0.22 0.08 - 0.10 0.08 - 0.10 0.14 - 0.19 0.22 - 0.36 0.34 - 0.48
20-39 1153 38.16 0.13 0.08 <LOD <LOD 0.08 0.16 0.31 0.42
0.11 - 0.15 0.07 - 0.09 0.07 - 0.09 0.13 - 0.20 0.23 - 0.39 0.33 - 0.51
40-59 1203 35.91 0.14 0.08 <LOD <LOD 0.08 0.16 0.28 0.38
0.11 - 0.17 0.07 - 0.09 0.07 - 0.10 0.12 - 0.19 0.21 - 0.35 0.31 - 0.45
60-79 1062 32.77 0.16 0.08 <LOD <LOD 0.08 0.17 0.29 0.42
0.13 - 0.18 0.07 - 0.09 0.07 - 0.09 0.13 - 0.20 0.25 - 0.34 0.33 - 0.51
Males 
Total,
age 6-79
2639 38.16 0.15 0.08 <LOD <LOD 0.08 0.15 0.28 0.39
0.11 - 0.19 0.07 - 0.09 0.07 - 0.09 0.12 - 0.19 0.21 - 0.34 0.29 - 0.48
6-11 524 39.89 0.35 0.08 <LOD <LOD 0.08 0.14 0.28 0.39
<LOD - 0.67 0.07 - 0.09 0.07 - 0.09 0.11 - 0.18 0.20 - 0.36 0.26 - 0.51
12-19 505 35.25 0.16 0.08 <LOD <LOD 0.08 0.15 0.26 0.39
0.10 - 0.22 0.07 - 0.09 0.07 - 0.10 0.13 - 0.18 0.20 - 0.33 0.29 - 0.49
20-39 510 40.20 -- -- <LOD <LOD 0.08 0.16 0.33 0.46
0.06 - 0.10 0.11 - 0.21 0.21 - 0.45 0.30 - 0.63
40-59 572 38.64 0.12 0.08 <LOD <LOD 0.08 0.15 0.26 0.37
0.09 - 0.15 0.06 - 0.09 0.06 - 0.10 0.12 - 0.19 0.19 - 0.32 0.25 - 0.48
60-79 528 36.74 0.12 0.07 <LOD <LOD 0.08 0.15 0.26 0.37
0.09 - 0.15 0.06 - 0.09 0.06 - 0.10 0.10 - 0.20 0.20 - 0.32 0.22 - 0.51
Females
Total,
age 6-79
2792 33.06 0.15 0.08 <LOD <LOD 0.09 0.17 0.30 0.41
0.13 - 0.18 0.07 - 0.09 0.08 - 0.10 0.15 - 0.19 0.25 - 0.35 0.37 - 0.45
6-11 508 36.22 0.15 0.08 <LOD <LOD 0.09 0.18 0.32 0.45
0.12 - 0.18 0.07 - 0.10 0.06 - 0.11 0.15 - 0.22 0.24 - 0.39 0.37 - 0.53
12-19 476 29.20 0.18 0.10 <LOD <LOD 0.10 0.19 0.31 0.42
0.10 - 0.26 0.09 - 0.11 0.09 - 0.12 0.16 - 0.22 0.22 - 0.41 0.33 - 0.50
20-39 643 36.55 0.13 0.08 <LOD <LOD 0.08 0.17 0.27 0.40
0.11 - 0.15 0.07 - 0.09 0.06 - 0.10 0.13 - 0.20 0.19 - 0.35 0.32 - 0.47
40-59 631 33.44 0.15 0.08 <LOD <LOD 0.09 0.16 0.31 0.40
0.11 - 0.19 0.07 - 0.10 0.07 - 0.11 0.12 - 0.21 0.24 - 0.38 0.33 - 0.48
60-79 534 28.84 0.19 0.09 <LOD <LOD 0.09 0.18 0.31 0.44
0.14 - 0.24 0.08 - 0.10 0.07 - 0.11 0.15 - 0.21 0.25 - 0.37 0.31 - 0.58
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.6c
Manganese (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5418 35.62 0.22 0.10 <LOD <LOD 0.09 0.19 0.39 0.70
0.18 - 0.26 0.09 - 0.11 0.08 - 0.10 0.16 - 0.23 0.31 - 0.48 0.57 - 0.84
6-11 1029 38.19 0.39 0.12 <LOD <LOD 0.11 0.23 0.51 0.82
0.28 - 0.49 0.11 - 0.14 0.09 - 0.13 0.19 - 0.28 0.41 - 0.61 0.66 - 0.98
12-19 980 32.35 0.18 0.08 <LOD <LOD 0.07 0.14 0.27 0.49
0.11 - 0.26 0.06 - 0.09 0.06 - 0.09 0.11 - 0.17 0.20 - 0.35 0.32 - 0.67
20-39 1149 38.29 0.19 0.09 <LOD <LOD 0.08 0.18 0.34 0.62
0.14 - 0.25 0.07 - 0.10 0.07 - 0.09 0.13 - 0.22 0.24 - 0.44 0.38 - 0.85
40-59 1198 36.06 0.21 0.10 <LOD <LOD 0.09 0.20 0.43 0.78
0.16 - 0.25 0.09 - 0.12 0.08 - 0.11 0.15 - 0.25 0.29 - 0.58 0.57 - 1.00
60-79 1062 32.77 0.24 0.11 <LOD <LOD 0.11 0.23 0.44 0.77
0.20 - 0.27 0.10 - 0.13 0.10 - 0.12 0.22 - 0.25 0.34 - 0.54 0.62 - 0.91
Males 
Total,
age 6-79
2630 38.29 0.17 0.08 <LOD <LOD 0.07 0.14 0.28 0.48
0.13 - 0.21 0.07 - 0.09 0.06 - 0.08 0.11 - 0.18 0.23 - 0.33 0.34 - 0.63
6-11 522 40.04 -- -- <LOD <LOD 0.10 0.21 0.47 0.74
0.08 - 0.12 0.16 - 0.26 0.33 - 0.62 0.50 - 0.98
12-19 504 35.32 0.16 0.07 <LOD <LOD 0.06 0.12 0.23 0.31
0.09 - 0.23 0.06 - 0.08 0.05 - 0.08 0.10 - 0.14 0.18 - 0.28 0.16 - 0.47
20-39 508 40.35 -- -- <LOD <LOD 0.07 0.14 0.29 0.43
0.06 - 0.09 0.08 - 0.20 0.19 - 0.38 0.22 - 0.63
40-59 568 38.91 0.16 0.08 <LOD <LOD 0.07 0.14 0.27 0.55
0.11 - 0.21 0.06 - 0.09 0.05 - 0.09 0.10 - 0.18 0.21 - 0.33 0.23 - 0.86
60-79 528 36.74 0.13 0.08 <LOD <LOD 0.07 0.15 0.31 0.44
0.10 - 0.17 0.06 - 0.10 0.06 - 0.09 0.11 - 0.20 0.24 - 0.38 0.32 - 0.56
Females
Total,
age 6-79
2788 33.11 0.27 0.12 <LOD <LOD 0.12 0.24 0.50 0.85
0.21 - 0.32 0.11 - 0.14 0.11 - 0.13 0.21 - 0.27 0.40 - 0.61 0.70 - 0.99
6-11 507 36.29 0.32 0.13 <LOD <LOD 0.12 0.27 0.55 0.85
0.26 - 0.39 0.11 - 0.15 0.10 - 0.14 0.21 - 0.32 0.42 - 0.67 0.66 - 1.05
12-19 476 29.20 0.21 0.09 <LOD <LOD 0.08 0.16 0.41 0.62
0.09 - 0.33 0.07 - 0.11 0.06 - 0.10 0.11 - 0.20 0.30 - 0.52 0.43 - 0.81
20-39 641 36.66 0.25 0.11 <LOD <LOD 0.10 0.22 0.41 0.73
0.15 - 0.36 0.09 - 0.13 0.09 - 0.12 0.16 - 0.27 0.25 - 0.57 0.21 - 1.24
40-59 630 33.49 0.26 0.14 <LOD <LOD 0.12 0.26 0.54 0.87
0.20 - 0.32 0.12 - 0.16 0.10 - 0.15 0.20 - 0.32 0.40 - 0.68 0.70 - 1.04
60-79 534 28.84 0.33 0.16 <LOD <LOD 0.15 0.28 0.68 1.08
0.26 - 0.39 0.13 - 0.19 0.12 - 0.19 0.23 - 0.32 0.45 - 0.91 0.55 - 1.62
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.7 Mercury (CASRN 7439-97-6)

Mercury (Hg) is a naturally occurring soft, silver-white metal; it is the only metal that is a liquid at room temperature. Its liquid state has a very wide temperature range. It has a relatively high vapour pressure; as a result, it can be present at hazardous concentrations in air as a vapour. Mercury exists in elemental, inorganic, and organic forms (CCME, 1996). The most common organic mercury compounds in nature are methylmercury (monomethylmercury) and dimethylmercury. Mercury can be converted between its elemental, inorganic, and organic forms by a variety of processes, including biological transformation (CCME, 1996; Environment Canada, 2007a).

Use of mercury in consumer products has been limited. Mercury was used in certain products where its unique properties were useful, such as relays and switches, and scientific measuring devices (e.g., flame sensors for older gas-fired appliances, vacuum gauges, thermometers), but it has been phased out of most products, including thermometers and switches. It is still used in some medical devices and some dental fillings (amalgam). Use of mercury in button-cell batteries, which are commonly used in small electronic and hearing aids, has been greatly reduced in recent years (Environment Canada, 2007b).

Mercury is present in many lamps and lights, including all fluorescent lamps, mercury vapour lamps (also known as high intensity discharge or HID lamps), metal halide lamps, and sodium vapour lamps (Environment Canada, 2007a). Use of mercury in light bulbs is increasing because of widespread replacement of incandescent bulbs with compact fluorescent bulbs. Mercury is also used in laboratory reagents and as industrial catalysts. It is used in pharmaceuticals, disinfectants, and embalming solutions. Historically, it was used as an antimicrobial and preservative in paints and in some agricultural applications, including turf fungicides, but these practices have been mostly discontinued. A significant use of inorganic mercury is in dental amalgam; in Canada, dental amalgam is made up of 43-50.5% mercury, but it contributes only a small amount to the total daily exposure of Canadians to mercury (CCME, 1996; Environment Canada, 2007a).

Mercury is found throughout the environment, including in remote Arctic regions, due to its persistence, mobility, and tendency to accumulate in colder climates, although it is uncertain how much is natural and how much is anthropogenic. Anthropogenic sources of inorganic mercury in the environment include metal mining and smelting; combustion of fossil fuels, particularly coal; incineration of municipal wastes; cement production; and sewage sludge and wastewater (CCME, 1996; UNEP, 2002). Inorganic mercury may also be released to the environment following disposal of products containing mercury. Metabolism of inorganic mercury by micro-organisms in the environment creates organic mercury (methylmercury), which can bioaccumulate in terrestrial and aquatic food chains (ATSDR, 1999).

Exposure of the general population is primarily to methylmercury and occurs through the consumption of contaminated fish and seafood (Health Canada, 2007). To a much lesser extent, the general population is exposed to inorganic mercury from sources such as dental amalgams (Health Canada, 2007). Previous studies have shown that inorganic mercury comprises 14-26% of total blood mercury (Kingman et al., 1998; Passos et al., 2007; Oskarsson et al., 1996).

Approximately 95% of organic mercury is absorbed from the gastrointestinal tract following oral ingestion. Following absorption, organic mercury is distributed to all tissues, including hair, with highest accumulation in the kidneys (ATSDR, 1999). Organic mercury is de-methylated in the body to inorganic mercury, which accumulates primarily in the liver and kidneys. Methylmercury is estimated to have a biological half-life of approximately 50 days. The majority of mercury in the body is excreted via the feces, with a small amount excreted as inorganic mercury in the urine (ATSDR, 1999).

Exposure to mercury is commonly evaluated using mercury concentrations in blood and urine, although hair may also be used as a biomarker of mercury exposure (ATSDR, 1999). Typically, blood and urine mercury levels are reported as total mercury, which comprises both inorganic and organic mercury. The concentration of total mercury in blood is accepted as a reasonable biomeasure of methyl mercury exposure. Based on a review of existing data from other countries, the World Health Organization has estimated that the average total blood mercury concentration for the general population is approximately 8 μg/L; however, individuals with high fish consumption can have concentrations in blood as high as 200 μg/L (ATSDR, 1999). Typical total mercury concentrations in urine have been reported to be in the 4 to 5 μg/L range. Both blood and urine concentrations primarily reflect recent exposures to mercury; urinary mercury levels are also commonly used for assessment of long-term exposure to inorganic mercury (ATSDR, 1999).

Mercury is known to be toxic to both humans and the environment. The toxic effects of mercury depend on the form and the exposure route. Exposure to low concentrations or doses may not result in any observable symptoms (Health Canada, 2007). Inhalation of mercury vapour may cause respiratory, cardiovascular, kidney, and neurological effects. Exposure to elemental mercury is hazardous because of its potential release of toxic mercury vapour, which is readily absorbed into the body through inhalation. Elemental mercury is poorly absorbed through the digestive tract or the skin (ATSDR, 1999). Low-level exposure to inorganic mercury from dental amalgams has not been associated with neurologic effects in children or adults (Bates et al., 2004; Bellinger et al., 2007; DeRouen et al., 2006; Factor-Litvak et al., 2003).

The primary effects associated with oral exposure to organic mercury compounds are neurological effects and developmental neurotoxicity; effects are similar for both acute and chronic exposure. Symptoms of organic mercury toxicity include a tingling sensation in the extremities; impaired peripheral vision, hearing, taste, and smell; slurred speech; muscle weakness and an unsteady gait; irritability; memory loss; depression; and sleeping difficulties. Exposure of a fetus or young child to organic mercury can result in effects on the development of the nervous system, affecting fine motor function, attention, verbal learning, and memory (ATSDR, 1999; Health Canada, 2007).

The United Nations Environment Programme (UNEP) completed a global risk assessment for mercury, and concluded that there was "sufficient evidence of adverse impacts from mercury to warrant further international action to reduce the risks to human health and the environment" (UNEP, 2002). In Canada, several Canada-wide standards have been established to reduce the releases of mercury to the environment (CCME, 2005; Environment Canada, 2007a). The Surface Coating Materials Regulations, in effect under the Hazardous Products Act since April 2005, restrict the level of mercury to no more than 10 mg/kg in all surface coating materials advertised, sold, or imported into Canada (Health Canada, 2006). Mercury is controlled in a number of other products used by Canadians. For example, mercury is listed on the Cosmetic Ingredient Hotlist. The Food and Drug Regulations prohibit the use of mercury in most drugs. Under the Pest Control Products Act, mercury-based pesticides are not registered for use in Canada and the mercury levels in natural health products are also restricted.

The International Agency for Research on Cancer (IARC, 1993) determined that methylmercury compounds are possible human carcinogens (Group 2B), based on inadequate human data but sufficient animal data showing a link to certain cancers, particularly renal cancer. Metallic mercury and inorganic mercury compounds were determined to be not classifiable as to their carcinogenicity (Group 3B) (IARC, 1993).

Health Canada (2007) has adopted a provisional tolerable daily intake for mercury developed by the World Health Organization of 0.71 µg/kg body weight/day for adults, of which no more than 2/3 (0.47 µg/kg body weight/day) should be methyl­mercury, as well as a provisional tolerable weekly intake of 1.6 µg methylmercury/kg body weight/week for women who are or may become pregnant and for young children; exposures below these doses are not expected to result in adverse health effects. Health Canada (2004) has established a total mercury blood guidance value of 20 µg/L for the general adult population; a revised guidance value of 8 µg/L for children, pregnant women, and women of childbearing age has recently been recommended (Legrand et al., 2010). Health Canada (1986) established a maximum acceptable concentration of 0.001 mg/L (1 µg/L) for mercury in drinking water. In addition, the Food Directorate of Health Canada has established a guideline level of 0.5 parts per million (ppm) for total mercury in domestically produced and imported fish considered to be the major source of dietary exposure (Health Canada, 2004).

In a study carried out in British Columbia to assess the levels of trace elements in 61 non-smoking adults aged 30-65, the geometric mean and 95th percentile concentrations of total mercury in blood were 2.94 µg/L and 7.26 µg/L, respectively (Clark et al., 2007). In a separate study carried out in the region of Québec City, on 500 adults aged 18-65, the geometric mean and 90th percentile concentrations of total mercury in blood were 0.74 µg/L and 2.01 µg/L, respectively (INSPQ, 2004).

Total and inorganic mercury were measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey. Total mercury is presented as µg/L in blood, and inorganic mercury is presented as µg/L in blood and both µg/L and µg/g creatinine in urine (Tables 8.1.7a, 8.1.7b, 8.1.7c, 8.1.7d). Finding a measurable amount of mercury in blood or urine is an indicator of exposure to mercury and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for blood and urinary levels of total and inorganic mercury in the Canadian population.

Table 8.1.7a
Mercury (Total) - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 11.64 1.42 0.69 0.12 0.33 0.81 1.61 3.07 4.70
1.00 - 1.84 0.56 - 0.86 <LOD - 0.14 0.26 - 0.39 0.64 - 0.97 1.17 - 2.04 2.21 - 3.93 2.61 - 6.78
6-11 910 24.84 0.58 0.27 <LOD <LOD 0.28 0.66 1.37 2.08
0.44 - 0.73 0.22 - 0.32 0.23 - 0.34 0.47 - 0.85 1.07 - 1.67 1.27 - 2.88
12-19 945 20.85 0.64 0.31 <LOD 0.13 0.32 0.76 1.36 2.25
0.31 - 0.97 0.23 - 0.40 <LOD - 0.18 0.24 - 0.41 0.47 - 1.06 0.53 - 2.20 0.93 - 3.56
20-39 1165 8.76 1.28 0.65 0.12 0.30 0.77 1.49 3.10 4.89
0.87 - 1.69 0.52 - 0.82 <LOD - 0.16 0.24 - 0.36 0.62 - 0.92 0.93 - 2.06 1.97 - 4.24 2.45 - 7.32
40-59 1220 3.52 1.88 1.02 0.27 0.56 1.11 1.93 3.59 6.39
1.28 - 2.49 0.81 - 1.27 0.19 - 0.35 0.42 - 0.70 0.86 - 1.37 1.50 - 2.36 2.31 - 4.86 3.03 - 9.76
60-79 1079 4.73 1.55 0.87 0.17 0.47 0.97 1.89 3.41 4.83
1.05 - 2.06 0.66 - 1.16 <LOD - 0.26 0.33 - 0.61 0.70 - 1.23 1.23 - 2.54 2.43 - 4.38 2.73 - 6.92
Males 
Total,
age 6-79
2576 12.11 1.50 0.68 0.10 0.32 0.79 1.61 3.16 5.13
0.99 - 2.00 0.55 - 0.85 <LOD - 0.14 0.25 - 0.39 0.64 - 0.94 1.15 - 2.07 2.18 - 4.15 2.70 - 7.57
6-11 459 26.14 0.51 0.24 <LOD <LOD 0.26 0.62 1.19 2.05
0.32 - 0.71 0.19 - 0.31 0.18 - 0.33 0.39 - 0.84 0.52 - 1.86 0.96 - 3.13
12-19 489 20.65 0.65 0.29 <LOD 0.12 0.28 0.64 1.48 2.29
0.15 - 1.16 0.20 - 0.41 <LOD - 0.17 0.17 - 0.39 0.19 - 1.09 0.41 - 2.55 0.54 - 4.04
20-39 514 9.34 1.26 0.62 <LOD 0.27 0.73 1.51 3.18 4.61
0.82 - 1.70 0.47 - 0.80 0.19 - 0.36 0.56 - 0.90 0.72 - 2.30 1.71 - 4.65 2.60 - 6.63
40-59 577 3.47 2.08 1.04 0.28 0.59 1.07 1.83 3.42 6.84
1.12 - 3.03 0.82 - 1.32 0.19 - 0.37 0.43 - 0.75 0.81 - 1.32 1.52 - 2.15 1.28 - 5.56 1.42 - 12.26
60-79 537 4.28 1.73 0.98 0.21 0.51 1.05 2.20 3.57 5.67
1.09 - 2.37 0.73 - 1.31 0.10 - 0.31 0.37 - 0.66 0.69 - 1.40 1.61 - 2.79 1.80 - 5.34 1.35 - 9.99
Females
Total,
age 6-79
2743 11.19 1.34 0.70 0.13 0.33 0.83 1.58 3.00 4.45
0.96 - 1.72 0.56 - 0.89 0.10 - 0.16 0.25 - 0.40 0.63 - 1.03 1.15 - 2.00 2.14 - 3.87 2.55 - 6.36
6-11 451 23.50 0.66 0.29 <LOD 0.11 0.30 0.80 1.44 2.15
0.53 - 0.79 0.25 - 0.35 <LOD - 0.15 0.25 - 0.34 0.54 - 1.05 1.21 - 1.67 1.08 - 3.23
12-19 456 21.05 0.63 0.33 <LOD 0.15 0.36 0.83 1.19 2.23
0.46 - 0.79 0.26 - 0.42 <LOD - 0.21 0.27 - 0.45 0.60 - 1.05 0.43 - 1.96 1.32 - 3.15
20-39 651 8.29 1.30 0.70 0.16 0.33 0.80 1.49 2.67 4.77
0.85 - 1.76 0.52 - 0.92 0.10 - 0.22 0.23 - 0.42 0.59 - 1.02 0.96 - 2.02 1.69 - 3.65 2.07 - 7.46
40-59 643 3.58 1.69 0.99 0.24 0.53 1.16 2.02 3.65 5.35
1.19 - 2.20 0.77 - 1.28 0.14 - 0.34 0.36 - 0.69 0.88 - 1.44 1.44 - 2.60 2.21 - 5.10 2.02 - 8.67
60-79 542 5.17 1.39 0.79 0.13 0.40 0.92 1.70 3.33 4.37
0.99 - 1.80 0.59 - 1.05 <LOD - 0.22 0.21 - 0.58 0.71 - 1.12 1.20 - 2.19 2.47 - 4.19 2.97 - 5.77
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.7b
Mercury (inorganic) - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
1123 88.16 -- -- <LOD <LOD <LOD <LOD 0.56 0.88
<LOD - 0.73 0.41 - 1.36
6-11 221 96.38 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
12-19 204 98.04 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 247 88.66 -- -- <LOD <LOD <LOD <LOD <LOD 0.75
0.63 - 0.86
40-59 253 79.05 -- -- <LOD <LOD <LOD <LOD 0.77 1.43
<LOD - 1.25 0.54 - 2.32
60-79 198 79.80 -- -- <LOD <LOD <LOD <LOD 0.92 S
0.43 - 1.41
Males 
Total,
age 6-79
557 88.87 -- -- <LOD <LOD <LOD <LOD 0.49 0.88
<LOD - 0.75 <LOD - 1.51
6-11 110 95.45 -- -- <LOD <LOD <LOD <LOD <LOD S
12-19 117 98.29 -- -- <LOD <LOD <LOD <LOD <LOD S
20-39 113 92.92 -- -- <LOD <LOD <LOD <LOD <LOD S
40-59 115 81.74 -- -- <LOD <LOD <LOD <LOD 0.80 S
<LOD - 1.52
60-79 102 74.51 -- -- <LOD <LOD <LOD <LOD 0.92 S
<LOD - 0.61 <LOD - 1.48
Females
Total,
age 6-79
566 87.46 -- -- <LOD <LOD <LOD <LOD 0.60 0.88
0.42 - 0.77 0.48 - 1.27
6-11 111 97.30 -- -- <LOD <LOD <LOD <LOD <LOD S
12-19 87 97.70 -- -- S <LOD <LOD <LOD S S
20-39 134 85.07 -- -- <LOD <LOD <LOD <LOD 0.58 S
<LOD - 0.93
40-59 138 76.81 -- -- <LOD <LOD <LOD <LOD 0.75 S
0.41 - 1.10
60-79 96 85.42 -- -- S <LOD <LOD <LOD S S
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
  • S Any estimate based on fewer than the minimum number of respondents required according to the Statistics Act must be suppressed in order to ensure respondent confidentiality. See Section 6.0, Statistical Data Analysis, for further information.
Table 8.1.7c
Mercury (inorganic) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5444 49.63 -- -- <LOD <LOD 0.24 0.76 1.89 2.98
<LOD - 0.28 0.66 - 0.85 1.68 - 2.10 2.58 - 3.37
6-11 1028 66.05 -- -- <LOD <LOD <LOD 0.35 1.02 1.92
0.20 - 0.49 0.55 - 1.50 1.02 - 2.82
12-19 975 57.54 -- -- <LOD <LOD <LOD 0.43 1.20 2.32
0.32 - 0.55 0.76 - 1.64 1.52 - 3.11
20-39 1166 46.23 -- -- <LOD <LOD 0.23 0.60 1.41 2.31
<LOD - 0.27 0.47 - 0.73 1.08 - 1.74 1.86 - 2.76
40-59 1207 36.04 0.94 0.31 <LOD <LOD 0.38 1.03 2.55 3.50
0.69 - 1.19 0.26 - 0.37 0.29 - 0.47 0.79 - 1.27 1.86 - 3.23 2.23 - 4.77
60-79 1068 45.69 -- -- <LOD <LOD 0.25 0.73 2.02 3.07
<LOD - 0.34 0.50 - 0.96 1.47 - 2.57 2.58 - 3.56
Males 
Total,
age 6-79
2636 48.33 -- -- <LOD <LOD 0.24 0.70 1.78 2.69
<LOD - 0.29 0.57 - 0.83 1.61 - 1.95 2.35 - 3.03
6-11 520 65.38 -- -- <LOD <LOD <LOD 0.33 0.95 1.95
<LOD - 0.52 0.38 - 1.51 0.81 - 3.10
12-19 501 57.09 -- -- <LOD <LOD <LOD 0.33 0.76 1.24
0.24 - 0.43 0.52 - 0.99 0.75 - 1.74
20-39 512 47.07 -- -- <LOD <LOD 0.22 0.54 1.27 2.12
<LOD - 0.29 0.48 - 0.60 0.94 - 1.60 1.60 - 2.64
40-59 570 33.33 0.85 0.31 <LOD <LOD 0.40 0.98 2.16 3.17
0.64 - 1.06 0.25 - 0.39 0.29 - 0.50 0.79 - 1.17 1.40 - 2.91 1.75 - 4.60
60-79 533 40.71 -- -- <LOD <LOD 0.31 0.90 2.35 3.22
<LOD - 0.46 0.27 - 1.53 1.49 - 3.22 2.30 - 4.15
Females
Total,
age 6-79
2808 50.85 -- -- <LOD <LOD 0.24 0.80 2.05 3.18
<LOD - 0.28 0.66 - 0.93 1.73 - 2.37 2.77 - 3.60
6-11 508 66.73 -- -- <LOD <LOD <LOD 0.36 1.09 1.81
<LOD - 0.55 0.56 - 1.61 0.74 - 2.87
12-19 474 58.02 -- -- <LOD <LOD <LOD 0.57 1.79 2.98
0.29 - 0.84 0.77 - 2.80 1.73 - 4.24
20-39 654 45.57 -- -- <LOD <LOD 0.24 0.71 1.62 2.62
<LOD - 0.32 0.45 - 0.97 1.12 - 2.11 1.68 - 3.55
40-59 637 38.46 1.03 0.30 <LOD <LOD 0.33 1.13 2.74 3.56
0.67 - 1.38 0.24 - 0.39 <LOD - 0.46 0.76 - 1.50 2.00 - 3.48 1.94 - 5.19
60-79 535 50.65 -- -- <LOD <LOD <LOD 0.63 1.76 2.74
0.48 - 0.79 1.20 - 2.33 2.12 - 3.36
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.7d
Mercury (inorganic) (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5432 49.74 -- -- <LOD <LOD 0.26 0.73 1.67 2.56
<LOD - 0.30 0.62 - 0.83 1.50 - 1.84 2.16 - 2.97
6-11 1025 66.24 -- -- <LOD <LOD <LOD 0.48 1.31 2.01
0.32 - 0.63 0.60 - 2.02 1.33 - 2.69
12-19 975 57.54 -- -- <LOD <LOD <LOD 0.30 0.79 1.31
0.23 - 0.37 0.54 - 1.03 0.80 - 1.82
20-39 1162 46.39 -- -- <LOD <LOD 0.22 0.55 1.16 1.93
<LOD - 0.25 0.44 - 0.67 0.92 - 1.39 1.56 - 2.30
40-59 1202 36.19 0.87 0.40 <LOD <LOD 0.43 1.13 2.12 3.02
0.68 - 1.06 0.33 - 0.48 0.33 - 0.53 0.88 - 1.38 1.54 - 2.71 2.33 - 3.72
60-79 1068 45.69 -- -- <LOD <LOD 0.30 0.94 2.05 2.77
<LOD - 0.43 0.68 - 1.20 1.77 - 2.33 2.15 - 3.38
Males 
Total,
age 6-79
2628 48.48 -- -- <LOD <LOD 0.22 0.57 1.25 1.80
<LOD - 0.27 0.50 - 0.64 1.09 - 1.41 1.49 - 2.11
6-11 518 65.64 -- -- <LOD <LOD <LOD 0.46 1.28 1.78
<LOD - 0.61 0.61 - 1.96 1.32 - 2.23
12-19 501 57.09 -- -- <LOD <LOD <LOD 0.24 0.54 0.91
<LOD - 0.30 0.28 - 0.81 0.73 - 1.09
20-39 510 47.25 -- -- <LOD <LOD <LOD 0.40 0.77 1.15
<LOD - 0.23 0.34 - 0.46 0.57 - 0.97 0.90 - 1.39
40-59 566 33.57 0.66 0.31 <LOD <LOD 0.37 0.85 1.53 2.57
0.50 - 0.82 0.24 - 0.40 0.26 - 0.48 0.60 - 1.10 1.00 - 2.07 1.52 - 3.63
60-79 533 40.71 -- -- <LOD <LOD 0.27 0.93 1.76 2.35
<LOD - 0.44 0.47 - 1.40 1.31 - 2.21 1.47 - 3.22
Females
Total,
age 6-79
2804 50.93 -- -- <LOD <LOD 0.30 0.93 2.11 2.91
<LOD - 0.36 0.76 - 1.11 1.79 - 2.43 2.30 - 3.52
6-11 507 66.86 -- -- <LOD <LOD <LOD 0.49 1.35 2.38
<LOD - 0.74 0.43 - 2.27 1.33 - 3.44
12-19 474 58.02 -- -- <LOD <LOD <LOD 0.39 1.18 2.31
0.23 - 0.55 0.49 - 1.87 0.89 - 3.73
20-39 652 45.71 -- -- <LOD <LOD 0.26 0.72 1.79 2.51
<LOD - 0.33 0.54 - 0.90 1.27 - 2.31 1.77 - 3.26
40-59 636 38.52 1.08 0.51 <LOD <LOD 0.55 1.34 2.57 3.67
0.77 - 1.38 0.42 - 0.62 <LOD - 0.68 1.04 - 1.64 2.01 - 3.14 1.90 - 5.45
60-79 535 50.65 -- -- <LOD <LOD <LOD 0.94 2.26 2.98
0.65 - 1.23 1.79 - 2.73 2.19 - 3.78
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.8 Molybdenum (CASRN 7439-98-7)

Molybdenum (Mo) is a naturally occurring element found throughout the Earth's crust, which commonly exists in combination with other elements and does not occur as a free metal in nature. It is classified as a heavy metal. Molybdenum can occur in a range of oxidation states from -2 to +6 (IMOA, 2007a). Molybdenum is an essential trace element required for the maintenance of good health (IOM, 2001; WHO, 2003).

Molybdenum is found naturally in soil, sediment, surface water, groundwater, plants, animals and humans. Anthropogenic sources of exposure include dust and fine particles produced during the refining or shaping of molybdenum or alloys containing molybdenum. Molybdenum may also be released to the environment through natural processes such as the weathering of soil. The primary use of molybdenum is in the steel industry as a component of steel alloys to increase strength and durability and aid in corrosion resistance (IMOA, 2007b). Other uses of molybdenum include electrical contacts, spark plugs, X-ray tubes, filaments, screens, and grids for radio valves, glass-to-metal seals, nonferrous alloys, and pigments (WHO, 1996). Molybdenum compounds are also used in agriculture for the treatment of seeds and in the formulation of fertilizers to prevent molybdenum deficiency (WHO, 2003).

Ingestion of food is a route of exposure for the general population (WHO, 2003). Absorption of dietary molybdenum from the gastrointestinal tract ranges from 30 to 70% (WHO, 1996). Following gastrointestinal absorption, molybdenum rapidly appears in the blood and most organs (WHO, 1996). The highest concentrations of molybdenum are found in the liver, kidneys, and bones, although there is no apparent bioaccumulation of molybdenum in human tissues. Molybdenum is primarily excreted in the urine; when molybdenum intake is low, approximately 60% of ingested molybdenum is excreted in the urine, but when molybdenum intake is high, over 90% is excreted in the urine (IOM, 2001; Turnlund et al., 1995).

Molybdenum is considered to be a nutritionally essential trace element in both animals and humans, as it helps to metabolize proteins and acts as a cofactor for several human enzymes (WHO, 2003; US EPA, 1993). The Recommended Dietary Allowance (RDA) is 45 μg/day for most adults, but 50 μg/day for pregnant and breastfeeding women (IOM, 2001). Average dietary intakes of molybdenum by adult men and women have been estimated at 109 and 76 µg/day, respectively. Molybdenum deficiency is normally only observed in people with metabolic defects (IOM, 2001).

Health Canada (2005) has adopted Tolerable Upper Intake Levels (UL) developed by the Institute of Medicine (IOM) for molybdenum, which account for both its essentiality and its potential toxicity. The ULs for molybdenum are 0.3 mg/day for children 1-3 years old, 0.6 mg/day for children 4-8 years old, 1.1 mg/day for children 9-13 years old, 1.7 mg/day for adolescents 14-18 years old, and 2 mg/day for adults. No UL was developed for infants 0-12 months old, but it is recommended that the sole source of intake is food and formula (IOM, 2001). There are limited toxicity data for molybdenum in humans since adverse effects observed in laboratory animals have not been observed in humans (IOM, 2001). However, chronic exposure to high levels of molybdenum has been associated with gout-like symptoms in humans, including high uric acid concentrations and joint pain (US EPA, 1993).

In a study undertaken in the region of Québec City, including 500 participants aged 18-65, the geometric mean and 90th percentile values for molybdenum in blood were 1.14 µg/L and 1.90 µg/L, respectively. In urine, the geometric mean and 90th percentile values were 44.25 µg/L and 115.16 µg/L, respectively (INSPQ, 2004). In a separate study carried out in British Columbia, which included 61 non-smoking adults aged 30-65, the geometric mean concentration and 90th percentile values for molybdenum in blood were 1.47 µg/L and 2.46 µg/L, respectively. The geometric mean and 95th percentile values in urine were 49.5 µg/g creatinine and 159.8 µg/g creatinine, respectively (Clark, 2007).

Molybdenum was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L in blood and both µg/L and µg/g creatinine in urine (Tables 8.1.8a, 8.1.8b, 8.1.8c). Finding a measurable amount of molybdenum in blood or urine is an indicator of exposure to molybdenum and does not necessarily mean that an adverse health effect will occur. Because molybdenum is an essential trace element required for the maintenance of health, its presence in the blood and urine is expected. These data provide reference ranges for blood and urinary levels of molybdenum in the Canadian population.

Table 8.1.8a
Molybdenum - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 0.09 0.76 0.67 0.40 0.51 0.66 0.86 1.16 1.38
0.73 - 0.79 0.66 - 0.69 0.39 - 0.42 0.50 - 0.53 0.64 - 0.68 0.83 - 0.89 1.11 - 1.21 1.31 - 1.46
6-11 910 0.00 1.09 0.85 0.57 0.66 0.80 1.05 1.35 1.60
0.75 - 1.43 0.83 - 0.87 0.55 - 0.59 0.65 - 0.68 0.76 - 0.84 0.98 - 1.12 1.31 - 1.39 1.51 - 1.69
12-19 945 0.11 0.75 0.68 0.41 0.52 0.65 0.85 1.10 1.31
0.69 - 0.80 0.63 - 0.72 0.38 - 0.44 0.49 - 0.55 0.60 - 0.71 0.79 - 0.92 1.00 - 1.19 1.10 - 1.52
20-39 1165 0.09 0.72 0.65 0.40 0.49 0.64 0.82 1.11 1.38
0.69 - 0.76 0.63 - 0.68 0.37 - 0.44 0.47 - 0.51 0.60 - 0.67 0.77 - 0.87 0.96 - 1.25 1.22 - 1.53
40-59 1220 0.08 0.70 0.64 0.38 0.49 0.64 0.81 1.08 1.24
0.67 - 0.73 0.61 - 0.67 0.34 - 0.41 0.47 - 0.52 0.60 - 0.67 0.75 - 0.87 1.01 - 1.14 1.17 - 1.30
60-79 1079 0.19 0.83 0.73 0.41 0.55 0.72 0.93 1.31 1.64
0.80 - 0.87 0.71 - 0.75 0.38 - 0.45 0.51 - 0.58 0.70 - 0.74 0.90 - 0.97 1.23 - 1.38 1.47 - 1.81
Males 
Total,
age 6-79
2576 0.12 0.76 0.67 0.41 0.50 0.65 0.85 1.12 1.35
0.71 - 0.81 0.65 - 0.68 0.39 - 0.42 0.49 - 0.51 0.64 - 0.67 0.81 - 0.88 1.04 - 1.19 1.24 - 1.46
6-11 459 0.00 1.27 0.87 0.57 0.68 0.82 1.06 1.35 1.59
0.59 - 1.96 0.84 - 0.90 0.53 - 0.61 0.65 - 0.71 0.74 - 0.89 0.96 - 1.16 1.30 - 1.41 1.50 - 1.68
12-19 489 0.00 0.77 0.70 0.43 0.54 0.67 0.87 1.12 1.35
0.70 - 0.84 0.65 - 0.74 0.39 - 0.48 0.51 - 0.58 0.62 - 0.71 0.81 - 0.93 0.99 - 1.24 0.98 - 1.72
20-39 514 0.00 0.69 0.64 0.41 0.49 0.63 0.80 1.03 1.30
0.65 - 0.74 0.61 - 0.67 0.36 - 0.45 0.46 - 0.51 0.59 - 0.67 0.75 - 0.85 0.85 - 1.21 1.08 - 1.52
40-59 577 0.17 0.70 0.63 0.38 0.48 0.64 0.80 1.04 1.21
0.65 - 0.74 0.60 - 0.67 0.33 - 0.43 0.44 - 0.52 0.59 - 0.68 0.73 - 0.86 0.97 - 1.10 1.11 - 1.30
60-79 537 0.37 0.79 0.69 0.40 0.51 0.69 0.90 1.21 1.55
0.74 - 0.84 0.65 - 0.74 0.36 - 0.44 0.46 - 0.57 0.64 - 0.73 0.85 - 0.95 1.11 - 1.32 1.36 - 1.74
Females
Total,
age 6-79
2743 0.07 0.76 0.68 0.40 0.52 0.67 0.88 1.19 1.40
0.74 - 0.79 0.66 - 0.71 0.37 - 0.43 0.50 - 0.55 0.65 - 0.70 0.83 - 0.92 1.14 - 1.24 1.31 - 1.49
6-11 451 0.00 0.89 0.83 0.56 0.65 0.78 1.03 1.34 1.60
0.84 - 0.94 0.80 - 0.86 0.53 - 0.59 0.62 - 0.67 0.74 - 0.81 0.96 - 1.09 1.22 - 1.46 1.37 - 1.84
12-19 456 0.22 0.72 0.65 0.39 0.49 0.63 0.83 1.09 1.26
0.67 - 0.78 0.60 - 0.71 0.35 - 0.43 0.45 - 0.53 0.55 - 0.71 0.72 - 0.94 0.98 - 1.19 1.13 - 1.39
20-39 651 0.15 0.75 0.67 0.40 0.51 0.64 0.85 1.19 1.42
0.69 - 0.81 0.64 - 0.71 0.35 - 0.44 0.48 - 0.54 0.61 - 0.68 0.78 - 0.92 0.99 - 1.39 1.17 - 1.68
40-59 643 0.00 0.70 0.64 0.37 0.50 0.64 0.82 1.11 1.26
0.66 - 0.74 0.60 - 0.68 0.33 - 0.42 0.46 - 0.54 0.60 - 0.68 0.75 - 0.90 1.00 - 1.22 1.16 - 1.35
60-79 542 0.00 0.88 0.77 0.44 0.58 0.75 0.99 1.33 1.64
0.82 - 0.93 0.74 - 0.80 0.39 - 0.50 0.55 - 0.62 0.72 - 0.78 0.93 - 1.05 1.28 - 1.38 1.48 - 1.81
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.8b
Molybdenum - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 0.00 53.08 36.30 10.12 20.21 40.41 70.60 107.80 138.28
49.50 - 56.66 33.20 - 39.68 8.58 - 11.65 17.18 - 23.23 37.51 - 43.31 66.71 - 74.48 99.90 - 115.69 128.01 - 148.55
6-11 1034 0.00 75.52 56.46 19.42 34.83 60.31 101.86 146.49 174.11
68.90 - 82.13 50.21 - 63.48 15.14 - 23.69 30.05 - 39.61 52.12 - 68.49 94.18 - 109.54 134.78 - 158.20 161.10 - 187.11
12-19 983 0.00 74.32 53.74 15.42 33.18 62.96 100.18 134.76 172.91
65.34 - 83.29 46.47 - 62.15 11.25 - 19.59 24.49 - 41.87 55.38 - 70.54 88.69 - 111.67 119.78 - 149.75 149.75 - 196.08
20-39 1169 0.00 55.40 37.81 10.43 20.41 44.07 73.51 106.37 138.78
49.63 - 61.17 33.22 - 43.05 7.45 - 13.41 16.01 - 24.80 38.80 - 49.34 67.82 - 79.20 96.49 - 116.25 113.29 - 164.27
40-59 1223 0.00 44.64 30.52 8.79 16.00 33.63 60.12 94.71 117.92
41.70 - 47.58 28.10 - 33.14 7.04 - 10.55 12.74 - 19.27 30.82 - 36.44 55.97 - 64.27 83.44 - 105.99 103.00 - 132.85
60-79 1083 0.00 41.96 30.35 9.88 17.96 32.31 54.50 83.00 106.63
39.42 - 44.50 27.66 - 33.31 8.35 - 11.40 15.46 - 20.45 28.94 - 35.69 50.92 - 58.08 74.11 - 91.88 96.19 - 117.07
Males 
Total,
age 6-79
5492 0.00 53.08 36.30 10.12 20.21 40.41 70.60 107.80 138.28
49.50 - 56.66 33.20 - 39.68 8.58 - 11.65 17.18 - 23.23 37.51 - 43.31 66.71 - 74.48 99.90 - 115.69 128.01 - 148.55
6-11 1034 0.00 75.52 56.46 19.42 34.83 60.31 101.86 146.49 174.11
68.90 - 82.13 50.21 - 63.48 15.14 - 23.69 30.05 - 39.61 52.12 - 68.49 94.18 - 109.54 134.78 - 158.20 161.10 - 187.11
12-19 983 0.00 74.32 53.74 15.42 33.18 62.96 100.18 134.76 172.91
65.34 - 83.29 46.47 - 62.15 11.25 - 19.59 24.49 - 41.87 55.38 - 70.54 88.69 - 111.67 119.78 - 149.75 149.75 - 196.08
20-39 1169 0.00 55.40 37.81 10.43 20.41 44.07 73.51 106.37 138.78
49.63 - 61.17 33.22 - 43.05 7.45 - 13.41 16.01 - 24.80 38.80 - 49.34 67.82 - 79.20 96.49 - 116.25 113.29 - 164.27
40-59 1223 0.00 44.64 30.52 8.79 16.00 33.63 60.12 94.71 117.92
41.70 - 47.58 28.10 - 33.14 7.04 - 10.55 12.74 - 19.27 30.82 - 36.44 55.97 - 64.27 83.44 - 105.99 103.00 - 132.85
60-79 1083 0.00 41.96 30.35 9.88 17.96 32.31 54.50 83.00 106.63
39.42 - 44.50 27.66 - 33.31 8.35 - 11.40 15.46 - 20.45 28.94 - 35.69 50.92 - 58.08 74.11 - 91.88 96.19 - 117.07
Females
Total,
age 6-79
2830 0.00 47.22 31.23 8.60 16.56 34.29 62.85 98.38 120.80
42.63 - 51.81 27.68 - 35.23 6.66 - 10.54 13.70 - 19.42 30.30 - 38.28 57.35 - 68.34 90.73 - 106.03 108.62 - 132.99
6-11 510 0.00 72.12 54.03 17.73 33.51 58.38 100.04 141.34 169.78
61.75 - 82.49 46.97 - 62.14 13.37 - 22.10 27.83 - 39.19 48.97 - 67.80 86.17 - 113.91 113.37 - 169.31 143.34 - 196.21
12-19 478 0.00 72.02 50.16 12.96 28.13 58.41 104.70 134.54 168.53
61.16 - 82.87 40.41 - 62.27 7.74 - 18.18 18.87 - 37.40 48.27 - 68.56 89.84 - 119.57 113.93 - 155.15 142.69 - 194.37
20-39 655 0.00 50.40 34.08 9.47 18.13 39.07 68.87 95.10 114.55
41.31 - 59.49 28.55 - 40.69 5.65 - 13.29 13.45 - 22.81 31.81 - 46.33 59.06 - 78.68 85.85 - 104.35 93.11 - 135.99
40-59 645 0.00 36.79 24.50 6.19 13.23 27.63 51.02 75.30 99.08
33.09 - 40.49 21.53 - 27.88 3.99 - 8.38 10.77 - 15.69 23.75 - 31.50 45.37 - 56.66 65.46 - 85.14 89.46 - 108.70
60-79 542 0.00 36.68 25.72 8.12 14.67 27.19 48.86 74.11 91.95
32.74 - 40.62 22.03 - 30.03 5.99 - 10.24 11.37 - 17.97 21.80 - 32.58 45.18 - 52.54 68.17 - 80.04 73.98 - 109.92
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.8c
Molybdenum (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 0.00 53.67 43.89 20.59 29.78 43.20 64.11 95.98 121.58
50.70 - 56.64 41.89 - 45.98 19.17 - 22.02 28.11 - 31.44 41.82 - 44.58 61.15 - 67.07 88.68 - 103.28 112.49 - 130.67
6-11 1031 0.00 100.32 87.00 46.89 62.77 84.59 121.86 173.32 217.99
95.10 - 105.53 83.51 - 90.64 43.45 - 50.33 60.39 - 65.16 79.41 - 89.78 114.29 - 129.42 153.07 - 193.57 194.33 - 241.64
12-19 982 0.00 56.26 46.79 22.12 32.06 46.80 69.75 96.88 114.07
50.26 - 62.26 42.90 - 51.02 19.46 - 24.77 27.99 - 36.13 42.66 - 50.94 63.23 - 76.28 84.01 - 109.75 101.92 - 126.21
20-39 1165 0.00 50.78 42.19 20.19 29.80 42.44 59.30 87.36 112.16
46.37 - 55.19 39.72 - 44.82 17.97 - 22.41 27.12 - 32.47 39.50 - 45.37 54.88 - 63.72 75.86 - 98.85 94.91 - 129.41
40-59 1218 0.00 46.60 39.08 19.84 26.46 39.11 54.79 82.17 107.33
43.64 - 49.56 36.41 - 41.95 16.93 - 22.75 23.38 - 29.54 36.67 - 41.55 50.00 - 59.57 77.49 - 86.85 95.57 - 119.09
60-79 1083 0.00 51.29 42.45 19.44 29.42 43.04 61.46 88.48 111.51
48.45 - 54.13 39.34 - 45.80 16.52 - 22.35 26.26 - 32.57 40.08 - 46.00 56.41 - 66.52 82.12 - 94.83 99.70 - 123.32
Males 
Total,
age 6-79
2653 0.00 51.03 41.65 19.86 27.31 40.58 61.18 90.81 117.53
47.84 - 54.22 39.95 - 43.42 18.44 - 21.27 25.41 - 29.21 38.97 - 42.19 56.89 - 65.46 81.68 - 99.94 107.02 - 128.04
6-11 522 0.00 103.21 89.36 48.06 64.94 87.52 123.72 182.14 226.52
95.67 - 110.76 83.55 - 95.57 41.28 - 54.85 61.14 - 68.73 80.72 - 94.32 114.99 - 132.45 153.41 - 210.86 200.83 - 252.22
12-19 504 0.00 58.68 48.24 23.04 32.45 48.82 72.32 100.50 114.51
50.73 - 66.64 43.67 - 53.28 20.73 - 25.34 27.62 - 37.28 44.47 - 53.16 65.29 - 79.35 85.68 - 115.32 92.78 - 136.24
20-39 512 0.00 45.55 38.40 18.09 25.70 38.93 57.16 80.77 97.49
41.27 - 49.83 35.81 - 41.19 16.43 - 19.75 21.66 - 29.73 35.46 - 42.41 50.93 - 63.39 67.16 - 94.39 73.78 - 121.20
40-59 574 0.00 44.49 37.46 20.02 25.20 36.65 51.37 80.77 105.08
40.80 - 48.17 35.04 - 40.05 17.62 - 22.41 23.36 - 27.04 34.80 - 38.50 47.08 - 55.66 70.93 - 90.61 84.70 - 125.46
60-79 541 0.00 45.54 38.33 18.22 26.45 38.26 56.04 77.76 97.54
42.11 - 48.97 34.63 - 42.43 14.99 - 21.45 22.84 - 30.06 34.40 - 42.11 50.22 - 61.85 69.61 - 85.90 85.34 - 109.74
Females
Total,
age 6-79
2826 0.00 56.30 46.24 21.52 31.94 45.93 66.36 100.92 127.94
52.87 - 59.73 43.55 - 49.09 19.08 - 23.97 29.97 - 33.92 43.37 - 48.48 62.54 - 70.18 91.68 - 110.15 115.75 - 140.14
6-11 509 0.00 97.26 84.59 46.66 59.66 81.40 118.18 164.77 196.53
88.59 - 105.94 79.00 - 90.58 42.27 - 51.05 54.87 - 64.45 75.34 - 87.45 104.37 - 131.99 140.07 - 189.46 153.78 - 239.28
12-19 478 0.00 53.61 45.25 20.68 31.01 44.33 67.03 90.61 113.55
47.53 - 59.70 40.57 - 50.47 17.49 - 23.86 25.84 - 36.17 38.28 - 50.38 58.31 - 75.75 71.25 - 109.97 101.51 - 125.60
20-39 653 0.00 56.05 46.39 24.40 31.92 45.73 62.24 96.75 127.61
48.98 - 63.12 42.34 - 50.83 22.62 - 26.19 30.22 - 33.62 41.37 - 50.10 54.57 - 69.92 79.36 - 114.14 80.82 - 174.40
40-59 644 0.00 48.68 40.75 19.08 28.53 41.39 60.17 86.43 107.84
44.59 - 52.77 37.01 - 44.86 14.70 - 23.46 23.32 - 33.73 38.12 - 44.66 54.55 - 65.79 74.36 - 98.50 93.47 - 122.21
60-79 542 0.00 56.57 46.62 20.61 32.70 48.32 68.63 94.57 125.21
53.25 - 59.88 42.93 - 50.62 16.01 - 25.21 27.92 - 37.47 42.30 - 54.34 60.30 - 76.95 83.63 - 105.51 111.61 - 138.81
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.9 Nickel (CASRN 7440-02-0)

Nickel (Ni) is a naturally occurring metal found in many types of rock. It is the 24th most abundant element in the Earth's crust and in its pure form is hard and silvery-white. However, nickel occurs most frequently in combination with sulphur, arsenic, and antimony. Nickel is a very reactive heavy metal that forms various divalent compounds, including nickel sulphate, nickel oxide, nickel sulphide, nickel subsulphide, and nickel carbonate. Canada was ranked as the second largest producer of nickel in the world in 1990, with Ontario (Sudbury) and Manitoba (Thompson) producing 65% and 35%, respectively, of the Canadian nickel (Environment Canada & Health Canada, 1994).

Due to its unique physical properties, nickel is commonly combined with other metals, including iron, copper, chromium, and zinc to form alloys. Nickel alloys are used in metal coins, jewellery, and heat exchangers. Nickel compounds are used in nickel plating, batteries, ceramic colouring, and as catalysts to increase rates of chemical reactions. Nickel is also a component of stainless steel, which has widespread application in a variety of home, medical, and industrial settings (ATSDR, 2005; CCME, 1996).

Nickel is released into the environment as a result of natural processes, including weathering of geological deposits, and also as a result of human activities, including mining, smelting, refining and other metal operations, fuel combustion, electric power generation and waste incineration (Environment Canada & Health Canada, 1994).

Given its natural abundance in the environment, everyone is exposed to small amounts of nickel. The main source of exposure for the general population is food. Other sources of nickel exposure include air, drinking water, soil, and household dust. Nickel exposure can also occur through dermal contact with alloys containing nickel (e.g., jewellery), and through dermal contact with nickel-containing products, such as cosmetics (generally present as an impurity); household cleaning and bleaching agents; and, medical products, such as joint implants, intrauterine devices, and acupuncture needles (ATSDR, 2005; Basketter et al., 2003). Nickel exposure can also occur from inhalation of cigarette smoke (ATSDR, 2005).

Nickel and nickel compounds are absorbed from the respiratory tract and to a lesser extent, from the gastrointestinal tract and skin. Approximately 20-35% of inhaled nickel is absorbed into the blood from the respiratory tract following inhalation (ATSDR, 2005), while only 1-10% of ingested nickel is absorbed, depending largely on the composition of the diet (WHO, 1991). Nickel has been measured in a variety of organs, including the lungs, thyroid, adrenals, kidneys, heart, liver, brain, spleen, and pancreas (ATSDR, 2005). Nickel is excreted in urine and feces, and has an estimated elimination half-life of 17 to 48 hours (Nieboer & Fletcher, 2001). Nickel can be measured in urine, serum, whole blood, feces, hair, sweat, and breast milk; urine is the most commonly used matrix for biological monitoring of nickel (Sunderman, 1993).

Studies indicate that nickel is an essential element in a number of laboratory animal species, and it has been postulated to be an essential element in humans (Environment Canada & Health Canada, 1994). Although there may be benefits from small doses of nickel, exposure to high levels may result in adverse health effects. These effects are dependent on the route of exposure and, in the case of inhalation, the species of nickel. Allergy to nickel is common and can cause severe contact dermatitis. The condition can be painful, but is not life threatening and can be managed by avoiding extended contact between the skin and nickel-containing jewellery, buttons, belt buckles, and similar items (ATSDR, 2005).

Health Canada and Environment Canada assessed nickel and its various compounds and concluded that metallic nickel was not a concern for human health at current levels of exposure (Environment Canada and Health Canada, 1994). However, the "oxidic" (including nickel oxide, nickel-copper oxide, nickel-silicate oxides, and complex oxides), "sulphidic" (including nickel subsulphide), and "soluble" (primarily nickel sulphate and nickel chloride) nickel groups, as a whole, are entering the environment in a quantity or concentration or under conditions that may constitute a danger in Canada to human life or health.

Health Canada has classified metallic nickel as VI: unclassifiable with respect to carcinogenicity in humans (Health Canada, 1996). However, oxidic, sulphidic, and soluble nickel are classified as a human carcinogen (Group I) for inhalation exposure (Health Canada, 1996). Health Canada (2005) has adopted Tolerable Upper Intake Levels (UL) developed by the Institute of Medicine (IOM) for nickel (IOM, 2001). The UL for nickel is 0.2 to 0.6 mg/day for children aged 1-13, and 1.0 mg/day for those over the age of 14 (Health Canada, 2005).

In a study carried out in 2001 in the Québec City region, in 500 participants aged 18-65, the geometric mean and 90th percentile values of nickel in blood were <0.59 µg/L and 0.85 µg/L, respectively. The geometric mean and 90th percentile values of nickel in urine were 1.78 µg/L and 4.46 µg/L, respectively (INSPQ, 2004).

Nickel was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L blood and both µg/L and µg/g creatinine in urine (Tables 8.1.9a, 8.1.9b, 8.1.9c). Finding a measurable amount of nickel in blood or urine is an indicator of exposure to nickel and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for blood and urinary levels of nickel in the Canadian population.

Table 8.1.9a
Nickel - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 6.69 0.75 0.62 <LOD 0.47 0.58 0.59 1.23 1.70
0.65 - 0.84 0.55 - 0.68 <LOD - 0.45 0.40 - 0.53 0.53 - 0.63 <LOD - 1.03 1.00 - 1.46 1.32 - 2.08
6-11 910 6.37 0.86 0.67 <LOD 0.47 0.55 1.06 1.52 2.13
0.72 - 1.01 0.59 - 0.76 <LOD - 0.42 0.43 - 0.52 0.54 - 0.56 0.45 - 1.66 1.17 - 1.87 1.53 - 2.74
12-19 945 7.20 0.78 0.63 <LOD 0.45 0.55 0.92 1.40 1.78
0.65 - 0.92 0.55 - 0.72 <LOD - 0.42 0.40 - 0.50 0.54 - 0.56 0.38 - 1.45 1.01 - 1.79 1.41 - 2.15
20-39 1165 6.95 0.72 0.61 <LOD 0.50 0.56 0.58 1.18 1.58
0.65 - 0.79 0.56 - 0.66 <LOD - 0.44 0.43 - 0.57 0.54 - 0.59 <LOD - 0.83 0.99 - 1.37 1.15 - 2.02
40-59 1220 6.80 0.72 0.60 <LOD 0.46 0.58 0.59 1.19 1.64
0.61 - 0.83 0.53 - 0.69 <LOD - 0.46 0.38 - 0.54 0.52 - 0.63 <LOD - 0.94 0.94 - 1.43 1.22 - 2.06
60-79 1079 6.12 0.78 0.63 <LOD 0.47 0.57 0.92 1.22 1.64
0.67 - 0.89 0.57 - 0.70 <LOD - 0.43 0.41 - 0.52 0.54 - 0.60 0.37 - 1.48 1.04 - 1.40 1.10 - 2.18
Males 
Total,
age 6-79
2576 6.72 0.72 0.60 <LOD 0.47 0.55 0.58 1.19 1.52
0.63 - 0.81 0.54 - 0.67 <LOD - 0.45 0.42 - 0.51 0.53 - 0.56 <LOD - 0.95 1.00 - 1.39 1.19 - 1.86
6-11 459 8.06 0.87 0.66 <LOD 0.46 0.55 1.03 1.53 2.26
0.71 - 1.02 0.58 - 0.74 <LOD - 0.36 0.40 - 0.52 0.54 - 0.56 0.39 - 1.68 1.20 - 1.85 1.59 - 2.94
12-19 489 7.98 0.77 0.62 <LOD 0.45 0.55 1.00 1.41 1.77
0.65 - 0.90 0.55 - 0.70 <LOD - 0.38 0.41 - 0.48 0.54 - 0.56 0.44 - 1.57 1.06 - 1.76 1.40 - 2.13
20-39 514 5.84 0.67 0.59 <LOD 0.47 0.55 0.58 1.16 1.32
0.58 - 0.77 0.53 - 0.65 <LOD - 0.46 0.43 - 0.51 0.53 - 0.56 0.45 - 0.71 1.06 - 1.26 1.15 - 1.48
40-59 577 6.93 0.69 0.59 0.36 0.46 0.54 0.58 1.17 1.46
0.59 - 0.79 0.51 - 0.68 <LOD - 0.49 0.40 - 0.52 0.53 - 0.56 <LOD - 0.97 0.92 - 1.43 1.05 - 1.88
60-79 537 5.03 0.77 0.63 <LOD 0.46 0.55 0.89 1.27 1.73
0.68 - 0.87 0.57 - 0.69 <LOD - 0.43 0.41 - 0.52 0.54 - 0.57 0.37 - 1.41 1.05 - 1.49 1.15 - 2.30
Females
Total,
age 6-79
2743 6.67 0.77 0.63 <LOD 0.46 0.58 0.59 1.29 1.83
0.67 - 0.88 0.56 - 0.70 <LOD - 0.45 0.39 - 0.53 0.53 - 0.63 <LOD - 1.11 0.98 - 1.60 1.42 - 2.25
6-11 451 4.66 0.86 0.68 0.37 0.48 0.55 1.09 1.43 1.91
0.69 - 1.04 0.59 - 0.78 <LOD - 0.46 0.44 - 0.53 0.54 - 0.57 0.59 - 1.59 1.04 - 1.82 1.19 - 2.63
12-19 456 6.36 0.80 0.63 <LOD 0.45 0.55 0.59 1.39 1.80
0.63 - 0.96 0.53 - 0.75 <LOD - 0.46 0.38 - 0.51 0.54 - 0.56 <LOD - 1.34 0.92 - 1.86 1.26 - 2.35
20-39 651 7.83 0.77 0.63 <LOD 0.47 0.57 0.59 1.34 1.96
0.69 - 0.85 0.57 - 0.69 <LOD - 0.43 0.41 - 0.53 0.54 - 0.59 <LOD - 1.10 0.89 - 1.79 1.53 - 2.39
40-59 643 6.69 0.75 0.61 <LOD 0.44 0.58 0.59 1.24 1.79
0.62 - 0.88 0.53 - 0.70 <LOD - 0.45 0.37 - 0.52 0.52 - 0.63 <LOD - 0.94 0.98 - 1.51 1.33 - 2.24
60-79 542 7.20 0.78 0.63 <LOD 0.47 0.57 0.95 1.17 1.59
0.64 - 0.93 0.55 - 0.72 <LOD - 0.42 0.40 - 0.54 0.54 - 0.60 0.36 - 1.54 0.99 - 1.35 1.04 - 2.14
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.9b
Nickel - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5491 3.15 1.62 1.10 0.35 0.65 1.16 2.03 3.28 4.47
1.53 - 1.71 1.04 - 1.18 0.31 - 0.38 0.61 - 0.69 1.09 - 1.23 1.90 - 2.16 3.01 - 3.55 4.08 - 4.85
6-11 1034 2.80 1.91 1.30 0.38 0.79 1.43 2.54 3.79 5.03
1.64 - 2.17 1.10 - 1.55 0.24 - 0.52 0.68 - 0.90 1.21 - 1.66 2.18 - 2.90 3.32 - 4.26 4.26 - 5.81
12-19 983 1.73 2.12 1.52 0.49 0.99 1.61 2.59 4.20 5.33
1.91 - 2.34 1.38 - 1.69 0.38 - 0.59 0.88 - 1.10 1.53 - 1.69 2.32 - 2.85 3.62 - 4.79 4.22 - 6.45
20-39 1168 3.68 1.43 1.00 0.32 0.63 1.06 1.76 2.79 3.71
1.28 - 1.58 0.89 - 1.13 0.27 - 0.37 0.56 - 0.70 0.95 - 1.16 1.53 - 2.00 2.37 - 3.21 3.15 - 4.28
40-59 1223 5.07 1.56 1.03 0.33 0.59 1.06 2.02 3.20 4.63
1.46 - 1.66 0.96 - 1.12 0.29 - 0.37 0.53 - 0.65 0.95 - 1.17 1.87 - 2.17 2.84 - 3.55 3.34 - 5.91
60-79 1083 2.03 1.64 1.13 0.40 0.65 1.13 1.95 3.27 4.68
1.49 - 1.78 1.06 - 1.21 0.35 - 0.46 0.59 - 0.72 1.07 - 1.19 1.80 - 2.11 2.66 - 3.88 3.82 - 5.53
Males 
Total,
age 6-79
2662 2.85 1.66 1.15 0.38 0.71 1.19 2.04 3.46 4.57
1.55 - 1.77 1.09 - 1.21 0.35 - 0.42 0.66 - 0.76 1.13 - 1.26 1.89 - 2.19 3.06 - 3.87 3.80 - 5.33
6-11 524 3.05 1.88 1.30 0.36 0.87 1.49 2.63 3.66 4.63
1.56 - 2.20 1.01 - 1.67 <LOD - 0.57 0.65 - 1.08 1.16 - 1.82 2.15 - 3.11 3.10 - 4.23 4.03 - 5.22
12-19 505 1.19 1.93 1.43 0.47 0.98 1.49 2.26 3.80 4.81
1.68 - 2.19 1.27 - 1.60 0.37 - 0.57 0.85 - 1.11 1.32 - 1.66 2.01 - 2.52 2.86 - 4.74 3.14 - 6.48
20-39 514 3.89 1.43 1.01 0.33 0.68 1.08 1.62 2.82 3.77
1.21 - 1.64 0.90 - 1.12 0.23 - 0.43 0.59 - 0.78 1.00 - 1.16 1.31 - 1.93 2.05 - 3.59 3.02 - 4.51
40-59 578 4.33 1.66 1.12 0.38 0.63 1.13 2.06 3.54 5.44
1.46 - 1.86 0.99 - 1.26 0.30 - 0.47 0.52 - 0.74 0.93 - 1.32 1.74 - 2.38 2.99 - 4.09 4.51 - 6.37
60-79 541 1.66 1.78 1.25 0.47 0.72 1.27 2.14 3.73 5.54
1.52 - 2.05 1.14 - 1.38 0.43 - 0.51 0.65 - 0.80 1.12 - 1.41 1.76 - 2.52 2.69 - 4.76 3.56 - 7.52
Females
Total,
age 6-79
2829 3.43 1.58 1.06 0.33 0.60 1.11 2.03 3.15 4.37
1.47 - 1.70 0.97 - 1.17 0.28 - 0.37 0.52 - 0.67 0.98 - 1.24 1.88 - 2.18 2.93 - 3.37 3.71 - 5.03
6-11 510 2.55 1.94 1.31 0.43 0.78 1.35 2.36 3.95 5.44
1.68 - 2.19 1.16 - 1.48 0.30 - 0.57 0.70 - 0.85 1.14 - 1.57 1.98 - 2.74 3.37 - 4.53 4.48 - 6.40
12-19 478 2.30 2.33 1.64 0.49 0.99 1.85 3.02 4.42 5.75
2.06 - 2.60 1.40 - 1.93 0.23 - 0.75 0.81 - 1.17 1.63 - 2.07 2.67 - 3.38 3.55 - 5.29 4.00 - 7.50
20-39 654 3.52 1.43 1.00 0.31 0.59 1.05 1.82 2.78 3.36
1.22 - 1.64 0.82 - 1.20 0.21 - 0.41 0.50 - 0.69 0.85 - 1.26 1.42 - 2.21 2.38 - 3.18 2.25 - 4.47
40-59 645 5.74 1.46 0.96 0.31 0.51 1.03 1.94 3.01 3.79
1.30 - 1.62 0.85 - 1.08 0.23 - 0.39 0.41 - 0.60 0.87 - 1.20 1.75 - 2.13 2.63 - 3.38 2.08 - 5.51
60-79 542 2.40 1.50 1.03 0.34 0.59 1.03 1.77 3.02 4.30
1.35 - 1.64 0.92 - 1.14 0.25 - 0.43 0.50 - 0.67 0.89 - 1.17 1.57 - 1.96 2.46 - 3.58 3.35 - 5.25
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.9c
Nickel (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5478 3.16 1.77 1.34 0.56 0.83 1.32 2.08 3.27 4.51
1.66 - 1.89 1.27 - 1.41 0.53 - 0.58 0.78 - 0.88 1.26 - 1.39 1.97 - 2.19 2.95 - 3.60 3.97 - 5.04
6-11 1031 2.81 2.59 2.00 0.86 1.34 2.02 3.02 4.46 5.69
2.25 - 2.93 1.78 - 2.26 0.70 - 1.02 1.24 - 1.44 1.79 - 2.25 2.70 - 3.34 3.86 - 5.06 4.61 - 6.76
12-19 982 1.73 1.72 1.33 0.58 0.84 1.32 2.04 3.27 4.00
1.55 - 1.90 1.23 - 1.44 0.52 - 0.63 0.79 - 0.88 1.19 - 1.46 1.74 - 2.34 2.67 - 3.86 3.67 - 4.34
20-39 1164 3.69 1.45 1.12 0.47 0.72 1.13 1.69 2.61 3.91
1.30 - 1.60 1.02 - 1.23 0.42 - 0.52 0.66 - 0.78 1.01 - 1.26 1.53 - 1.85 2.22 - 3.00 2.92 - 4.89
40-59 1218 5.09 1.75 1.33 0.57 0.83 1.31 2.06 3.19 4.46
1.61 - 1.89 1.26 - 1.40 0.53 - 0.62 0.75 - 0.91 1.22 - 1.41 1.97 - 2.15 2.85 - 3.54 3.52 - 5.40
60-79 1083 2.03 2.10 1.58 0.67 0.98 1.57 2.43 3.88 5.27
1.92 - 2.29 1.50 - 1.66 0.59 - 0.76 0.90 - 1.06 1.48 - 1.67 2.29 - 2.58 3.42 - 4.34 4.76 - 5.79
Males 
Total,
age 6-79
2653 2.86 1.50 1.13 0.49 0.70 1.09 1.75 2.79 3.78
1.37 - 1.63 1.06 - 1.20 0.45 - 0.52 0.66 - 0.74 1.03 - 1.15 1.61 - 1.88 2.51 - 3.07 3.22 - 4.34
6-11 522 3.07 2.54 1.96 0.83 1.33 2.06 2.90 4.30 5.25
2.14 - 2.93 1.72 - 2.24 <LOD - 1.03 1.13 - 1.53 1.72 - 2.40 2.59 - 3.21 3.90 - 4.71 3.51 - 6.99
12-19 504 1.19 1.54 1.20 0.55 0.74 1.08 1.83 3.00 4.14
1.42 - 1.67 1.11 - 1.29 0.47 - 0.63 0.65 - 0.84 0.94 - 1.21 1.59 - 2.07 2.32 - 3.68 3.39 - 4.88
20-39 512 3.91 1.16 0.92 0.40 0.59 0.90 1.40 2.02 2.78
0.97 - 1.36 0.81 - 1.06 0.35 - 0.45 0.50 - 0.68 0.77 - 1.03 1.12 - 1.67 1.58 - 2.47 1.98 - 3.58
40-59 574 4.36 1.47 1.10 0.50 0.68 1.07 1.65 2.59 3.48
1.26 - 1.67 1.01 - 1.20 0.44 - 0.57 0.61 - 0.74 0.98 - 1.17 1.43 - 1.87 2.17 - 3.00 2.62 - 4.34
60-79 541 1.66 1.71 1.32 0.57 0.86 1.24 2.02 3.20 4.82
1.48 - 1.94 1.21 - 1.45 0.49 - 0.64 0.80 - 0.92 1.12 - 1.37 1.75 - 2.29 2.60 - 3.81 3.20 - 6.43
Females
Total,
age 6-79
2825 3.43 2.05 1.58 0.70 1.02 1.53 2.33 3.82 5.16
1.86 - 2.23 1.47 - 1.69 0.64 - 0.76 0.93 - 1.11 1.44 - 1.62 2.12 - 2.54 3.27 - 4.37 4.25 - 6.06
6-11 509 2.55 2.65 2.05 0.93 1.34 1.97 3.18 4.81 5.72
2.27 - 3.02 1.82 - 2.31 0.76 - 1.11 1.25 - 1.42 1.78 - 2.16 2.70 - 3.66 4.00 - 5.62 4.50 - 6.94
12-19 478 2.30 1.92 1.48 0.64 0.95 1.53 2.23 3.34 3.92
1.65 - 2.19 1.31 - 1.68 0.47 - 0.80 0.81 - 1.10 1.35 - 1.71 1.82 - 2.64 2.77 - 3.92 3.30 - 4.54
20-39 652 3.53 1.74 1.36 0.63 0.89 1.31 2.03 3.29 4.59
1.51 - 1.97 1.18 - 1.57 0.52 - 0.74 0.74 - 1.03 1.12 - 1.49 1.81 - 2.25 2.22 - 4.36 3.68 - 5.50
40-59 644 5.75 2.02 1.60 0.73 1.06 1.56 2.27 3.69 4.96
1.82 - 2.23 1.48 - 1.72 0.65 - 0.81 0.91 - 1.20 1.42 - 1.69 1.98 - 2.57 2.95 - 4.43 3.63 - 6.30
60-79 542 2.40 2.46 1.86 0.81 1.17 1.89 2.70 4.25 5.89
2.09 - 2.84 1.71 - 2.02 0.66 - 0.96 0.99 - 1.34 1.76 - 2.02 2.36 - 3.03 3.47 - 5.03 4.78 - 7.01
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.10 Selenium (CASRN 7782-49-2)

Selenium (Se) is a naturally occurring essential element that comprises a small fraction of the Earth's crust. It is a metalloid and cannot be broken down, but can be transformed by sunlight, water, and air to various oxidation states and forms. Selenium is present in the environment in inorganic form as selenide (Se2-), selenate (SeO42-), and selenite (SeO32-). It is widely distributed in the Earth's crust at concentrations averaging 0.09 mg/kg and is found in trace quantities in most plant and animal tissues (Schamberger, 1984). Selenium is an essential nutrient required for the maintenance of good health (ATSDR, 2003).

Elevated levels of selenium in the environment may occur naturally from weathering of heavy metal deposits and soils (CCME, 2007), or as the result of anthropogenic activities such as mining or metallurgical processes. Selenium is produced mainly as a by-product of copper refining and also from recycling of metal products. Other sources of selenium emissions include incinerator stacks, burning coal or oil, and any large-scale combustion processes due to the widespread distribution of selenium in nature.

Canada is one of the largest selenium producers and exporters globally. Historically, the primary use of selenium was in the electronics industry in the form of arsenic triselenide, used as a photoreceptor for photocopiers. However, arsenic triselenide has generally been replaced by more environmentally friendly compounds in recent years. As selenium has various electrical and conductive properties, it is also used in light meters, photoelectric and solar cells, semiconductors, and arc light electrodes. It is also used as a colourizing and decolourizing agent for glass and to reduce solar heat for architectural glass. It can be used to develop red, orange, and maroon pigments for ceramics, glazes, plastics, enamels, and paints, but this practice is generally restricted due to the potential for selenium toxicity. Selenium is also present in stainless steel, enamels, inks, rubber, pesticides, fungicides, batteries, explosives, and shampoos. Products containing selenium are generally considered non-toxic when used as directed, but the selenium may be released upon disposal if incinerated (CCME, 2007; ATSDR, 2003).

The Canadian population is exposed to selenium compounds in ambient air, drinking water, soil, and food. It is estimated that more than 98% of the total daily intake of selenium occurs through food consumption (IOM, 2000). Exposure to selenium may also occur from the use of therapeutic products, including shampoos used to treat dandruff and seborrheic dermatitis, and certain antifungal skin lotions. A Canadian study reported that adults consume an average of 113-220 μg selenium per day (Thompson et al., 1975).

Absorption of selenium is dependent on the chemical form, with organic forms (e.g., selenoamino acids such as selenomethionine and selenocysteine) absorbed more readily than inorganic forms, as well as on the overall exposure level, with absorption increasing when selenium levels in the body are low (IOM, 2000). Following ingestion, selenium is readily absorbed in the gastrointestinal tract. Selenium can also be absorbed through the lungs, with acidic forms absorbing more readily (CCME, 2007). Once inside the body, selenium generally concentrates in the liver and kidneys, regardless of the initial chemical form. Selenium can also be found in significant amounts in nails and hair (IOM, 2000). Approximately 50-80% of absorbed selenium is eliminated in the urine (Marier & Jaworski, 1983).

Selenium is an essential nutrient and a component of several proteins and enzymes in the body. Selenium aids in the defence of oxidative stress, the regulation of thyroid hormone action, and the regulation of the redox status of Vitamin C and other molecules (IOM, 2000). The Recommended Dietary Allowance (RDA) for Canadians is 15 µg/day for young infants, 20-30 µg/day for children up to age 12, and 55 µg/day for adolescents and adults (Health Canada, 2005).

As is generally the case with essential trace elements, selenium can have detrimental health effects when ingested at levels much greater than the recommended daily intake. The level at which selenium toxicity occurs is difficult to determine, as it is affected by the types of protein in the diet, levels of vitamin E, and the various forms of selenium present in the body (Health Canada, 1992). The symptoms of selenium deficiency and excess are similar. Oral intake of large amounts of selenium can result in nausea, vomiting, and diarrhea. Chronic levels of high selenium can cause selenosis, a disease that results in hair loss, nail brittleness, and neurological abnormalities (IOM, 2000; ATSDR, 2003; WHO, 2003). There is no evidence in humans of reproductive effects or developmental abnormalities; the International Agency for Research on Cancer (IARC) has determined that selenium is not classifiable as to its carcinogenicity to humans (Group 3) (IARC, 1987).

Health Canada (2005) has adopted Tolerable Upper Intake Levels (UL) developed by the Institute of Medicine (IOM) for selenium, which account for both its essentiality and its potential toxicity. The ULs for selenium are 45 µg/day for infants 0-6 months old, 60 µg/day for infants 7-12 months old, 90 μg/day for children 1-3 years old, 150 μg/day for children 4-8 years old, 280 μg/day for children 9-13 years old, and 400 μg/day for adolescents 14-18 years old and adults (IOM, 2000). A maximum acceptable concentration of 0.01 mg/L (10 µg/L) for selenium in drinking water has been established on the basis of health considerations and is currently under revision (Health Canada, 1992).

Selenium levels in the body following both short- and long-term exposure can be determined through blood and urine tests (IOM, 2000).

In a study carried out in the region of Québec City on adults aged 18-65, the geometric mean and 90th percentile values of selenium in urine were 63.19 µg/L and 132.65 µg/L, respectively. The geometric mean and 90th percentile values of selenium in blood were 221.17 µg/L and 261.45 µg/L, respectively (INSPQ, 2004).

Selenium was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L in blood and as both µg/L and µg/g creatinine in urine (Tables 8.1.10a, 8.1.10b, 8.1.10c). Finding a measurable amount of selenium in blood or urine is an indicator of exposure to selenium and does not necessarily mean that an adverse health effect will occur. Since it is an essential nutrient, its presence is expected. These data provide reference ranges for blood and urinary levels of selenium in the Canadian population.

Table 8.1.10a
Selenium - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 0.00 204.01 201.56 168.90 182.76 199.70 219.49 241.39 253.25
199.73 - 208.28 197.55 - 205.66 164.62 - 173.17 178.57 - 186.95 196.22 - 203.18 214.75 - 224.22 235.53 - 247.25 245.31 - 261.20
6-11 910 0.00 188.36 186.86 159.81 171.59 185.43 201.13 217.45 231.76
185.29 - 191.43 183.89 - 189.88 155.73 - 163.89 167.91 - 175.26 182.48 - 188.37 199.19 - 203.07 213.48 - 221.42 222.47 - 241.04
12-19 945 0.00 198.29 196.17 165.45 178.05 194.52 212.46 238.47 251.07
193.77 - 202.82 191.65 - 200.80 160.50 - 170.39 173.52 - 182.58 191.24 - 197.79 206.15 - 218.76 230.64 - 246.30 237.22 - 264.93
20-39 1165 0.00 205.62 202.73 169.82 185.37 199.88 219.55 242.30 252.76
200.17 - 211.08 198.42 - 207.13 165.96 - 173.68 180.41 - 190.34 195.85 - 203.92 214.53 - 224.56 233.49 - 251.12 238.95 - 266.56
40-59 1220 0.00 206.15 203.94 171.43 184.34 202.81 223.74 243.59 255.01
201.63 - 210.67 199.51 - 208.47 166.14 - 176.73 179.46 - 189.22 198.23 - 207.39 217.63 - 229.84 236.47 - 250.71 245.42 - 264.61
60-79 1079 0.00 206.35 204.01 172.11 186.16 201.16 223.22 243.95 256.45
199.87 - 212.83 197.92 - 210.28 167.59 - 176.62 180.99 - 191.32 194.89 - 207.42 215.79 - 230.66 234.54 - 253.36 241.97 - 270.94
Males 
Total,
age 6-79
2576 0.00 207.46 204.84 172.01 185.41 202.09 224.24 244.68 256.31
202.25 - 212.66 200.32 - 209.45 167.37 - 176.64 181.36 - 189.45 197.83 - 206.34 218.37 - 230.12 237.87 - 251.49 242.62 - 270.00
6-11 459 0.00 187.32 186.03 159.99 171.65 183.71 199.62 215.75 233.39
183.88 - 190.77 182.68 - 189.44 155.79 - 164.18 167.65 - 175.65 179.68 - 187.74 194.18 - 205.07 208.14 - 223.37 216.30 - 250.49
12-19 489 0.00 198.92 196.87 166.95 178.30 193.52 215.32 237.80 247.67
194.29 - 203.56 192.51 - 201.34 161.98 - 171.92 174.82 - 181.78 189.87 - 197.17 205.45 - 225.20 227.49 - 248.12 229.27 - 266.07
20-39 514 0.00 211.71 207.95 175.02 187.21 203.51 224.99 246.43 266.01
202.23 - 221.19 201.69 - 214.41 169.14 - 180.91 182.46 - 191.95 198.65 - 208.37 217.28 - 232.70 235.51 - 257.35 237.57 - 294.45
40-59 577 0.00 210.32 208.36 175.32 189.53 207.07 226.78 246.89 255.86
203.29 - 217.36 201.47 - 215.48 166.56 - 184.09 182.14 - 196.92 199.39 - 214.76 219.44 - 234.13 239.04 - 254.75 240.07 - 271.64
60-79 537 0.00 207.40 205.27 174.96 187.90 205.05 224.09 243.64 255.99
200.42 - 214.38 198.35 - 212.43 168.44 - 181.48 182.62 - 193.18 197.56 - 212.55 214.32 - 233.85 232.82 - 254.46 243.77 - 268.20
Females
Total,
age 6-79
2743 0.00 200.53 198.32 166.53 180.67 197.34 215.51 235.99 249.47
196.28 - 204.79 194.28 - 202.45 162.29 - 170.78 175.58 - 185.76 193.69 - 200.99 211.36 - 219.66 230.76 - 241.22 241.16 - 257.78
6-11 451 0.00 189.45 187.75 159.03 171.49 186.62 201.60 218.77 230.09
185.98 - 192.92 184.32 - 191.24 153.39 - 164.68 165.94 - 177.03 183.31 - 189.93 196.86 - 206.33 211.98 - 225.56 221.68 - 238.51
12-19 456 0.00 197.61 195.40 164.27 177.57 194.77 210.56 240.05 253.92
192.04 - 203.17 189.70 - 201.26 157.26 - 171.27 170.56 - 184.57 190.00 - 199.55 202.76 - 218.35 230.43 - 249.67 244.38 - 263.46
20-39 651 0.00 199.33 197.46 167.18 180.94 195.97 216.29 233.68 247.44
194.25 - 204.41 192.54 - 202.50 161.28 - 173.07 171.36 - 190.51 191.45 - 200.48 209.69 - 222.89 225.47 - 241.89 239.35 - 255.52
40-59 643 0.00 202.00 199.65 166.68 180.77 198.26 215.48 235.33 253.23
197.78 - 206.23 195.76 - 203.62 161.64 - 171.73 177.71 - 183.83 193.63 - 202.90 208.99 - 221.98 228.01 - 242.65 239.88 - 266.58
60-79 542 0.00 205.39 202.86 170.54 183.14 198.88 222.65 244.02 259.30
197.37 - 213.41 195.76 - 210.22 165.69 - 175.38 176.69 - 189.58 193.12 - 204.65 213.37 - 231.92 231.53 - 256.52 238.22 - 280.37
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.10b
Selenium - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 0.46 63.05 48.86 16.97 30.46 53.68 85.52 121.07 143.65
58.25 - 67.86 44.72 - 53.38 14.41 - 19.53 26.75 - 34.17 48.68 - 58.69 79.54 - 91.50 111.68 - 130.45 136.37 - 150.93
6-11 1034 0.48 74.79 60.20 22.41 40.23 67.55 102.57 129.49 153.69
68.52 - 81.05 53.89 - 67.24 18.81 - 26.02 33.41 - 47.05 60.85 - 74.25 91.61 - 113.54 118.79 - 140.19 144.13 - 163.25
12-19 983 0.00 78.02 62.62 22.20 42.53 70.74 103.51 139.74 160.27
70.10 - 85.93 54.89 - 71.42 16.22 - 28.18 32.87 - 52.18 62.95 - 78.53 92.95 - 114.08 127.71 - 151.76 143.57 - 176.97
20-39 1169 0.77 63.16 48.63 17.39 31.00 53.43 84.60 124.08 144.70
55.34 - 70.98 42.40 - 55.78 13.50 - 21.28 26.51 - 35.48 44.34 - 62.52 75.25 - 93.94 106.95 - 141.22 134.77 - 154.64
40-59 1223 0.74 59.35 45.15 14.44 26.53 48.67 82.71 116.62 140.57
56.39 - 62.31 42.32 - 48.18 11.43 - 17.44 23.19 - 29.87 44.67 - 52.66 77.27 - 88.15 109.17 - 124.07 133.42 - 147.72
60-79 1083 0.18 55.31 44.75 17.36 28.07 49.47 72.54 99.52 121.54
51.57 - 59.04 41.33 - 48.46 14.06 - 20.65 23.15 - 32.99 45.38 - 53.57 67.98 - 77.11 87.46 - 111.58 107.88 - 135.19
Males 
Total,
age 6-79
2662 0.23 71.23 56.94 21.45 37.91 62.77 94.98 132.16 152.46
66.18 - 76.27 52.58 - 61.67 18.48 - 24.41 34.30 - 41.53 57.64 - 67.91 85.75 - 104.22 124.41 - 139.91 140.29 - 164.63
6-11 524 0.38 77.27 62.51 23.78 42.53 68.27 104.54 132.75 165.76
69.49 - 85.05 52.92 - 73.84 15.38 - 32.19 33.16 - 51.90 57.49 - 79.05 91.10 - 117.97 118.37 - 147.12 147.16 - 184.36
12-19 505 0.00 80.79 66.34 25.98 46.00 71.15 110.23 140.31 162.39
73.23 - 88.35 59.09 - 74.49 18.93 - 33.04 38.41 - 53.59 62.50 - 79.79 99.79 - 120.66 128.27 - 152.34 137.87 - 186.91
20-39 514 0.58 71.49 55.71 17.74 37.46 63.80 94.15 132.98 152.00
62.06 - 80.91 48.03 - 64.62 9.55 - 25.93 29.82 - 45.10 54.70 - 72.90 82.81 - 105.48 120.66 - 145.31 126.99 - 177.01
40-59 578 0.17 70.60 55.74 20.33 35.22 59.62 100.06 132.92 157.69
66.79 - 74.41 52.54 - 59.13 18.00 - 22.67 30.87 - 39.57 52.69 - 66.54 91.18 - 108.93 122.02 - 143.83 145.49 - 169.90
60-79 541 0.00 62.35 53.26 23.05 38.10 55.66 78.57 109.17 134.63
56.57 - 68.12 48.83 - 58.08 20.99 - 25.12 34.93 - 41.26 50.64 - 60.68 68.07 - 89.07 93.42 - 124.92 125.94 - 143.32
Females
Total,
age 6-79
2830 0.67 54.89 41.93 14.15 24.50 44.83 75.76 108.03 129.34
49.98 - 59.80 37.73 - 46.61 11.83 - 16.47 20.59 - 28.40 39.22 - 50.43 69.46 - 82.06 97.02 - 119.04 117.91 - 140.77
6-11 510 0.59 72.17 57.85 21.14 36.95 67.26 101.80 128.17 150.44
65.34 - 78.99 52.33 - 63.95 17.13 - 25.16 29.78 - 44.12 61.21 - 73.31 88.67 - 114.93 114.51 - 141.84 132.57 - 168.30
12-19 478 0.00 74.98 58.77 19.95 37.06 68.35 96.59 136.49 159.25
65.52 - 84.44 48.72 - 70.90 9.62 - 30.29 23.00 - 51.13 57.65 - 79.05 85.96 - 107.22 121.55 - 151.42 139.82 - 178.69
20-39 655 0.92 54.76 42.40 16.40 27.39 42.13 72.59 109.00 132.25
47.23 - 62.29 36.55 - 49.20 13.18 - 19.63 21.68 - 33.09 33.36 - 50.91 60.93 - 84.25 86.77 - 131.23 112.45 - 152.06
40-59 645 1.24 48.22 36.66 11.83 21.00 40.04 68.24 94.13 116.21
44.50 - 51.94 33.16 - 40.52 9.41 - 14.26 16.26 - 25.75 34.45 - 45.64 62.54 - 73.93 87.97 - 100.30 107.42 - 125.01
60-79 542 0.37 48.84 38.14 13.48 22.25 40.59 66.35 90.11 112.15
44.10 - 53.57 33.37 - 43.60 10.83 - 16.14 17.88 - 26.63 32.32 - 48.86 59.99 - 72.71 81.62 - 98.59 102.34 - 121.97
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.10c
Selenium (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 0.46 65.22 59.09 34.55 44.10 57.83 77.17 102.86 126.49
62.02 - 68.41 56.45 - 61.86 32.48 - 36.62 41.95 - 46.25 54.44 - 61.22 72.66 - 81.67 97.24 - 108.49 115.33 - 137.65
6-11 1031 0.48 100.76 92.75 55.23 73.50 93.96 117.21 145.48 172.35
95.42 - 106.09 88.83 - 96.85 51.14 - 59.33 69.95 - 77.05 89.61 - 98.31 110.27 - 124.16 136.07 - 154.89 154.64 - 190.07
12-19 982 0.00 59.69 54.54 32.97 40.65 53.65 69.49 89.50 110.10
54.63 - 64.76 51.05 - 58.26 30.85 - 35.09 38.39 - 42.91 49.78 - 57.53 64.17 - 74.81 77.65 - 101.36 92.41 - 127.78
20-39 1165 0.77 59.40 54.26 32.49 41.07 52.46 70.03 95.69 105.82
55.86 - 62.94 51.23 - 57.47 29.80 - 35.18 38.34 - 43.80 49.10 - 55.81 64.61 - 75.46 85.68 - 105.70 89.37 - 122.28
40-59 1218 0.74 63.47 57.86 33.43 44.06 57.11 74.72 96.18 115.77
59.76 - 67.18 54.62 - 61.30 30.57 - 36.28 41.28 - 46.83 53.31 - 60.90 70.14 - 79.30 89.66 - 102.69 104.13 - 127.41
60-79 1083 0.18 67.72 62.58 39.22 47.96 62.20 79.31 103.88 119.86
64.13 - 71.31 59.36 - 65.98 36.16 - 42.27 44.44 - 51.48 58.85 - 65.55 75.68 - 82.94 94.94 - 112.81 108.00 - 131.72
Males 
Total,
age 6-79
5479 0.46 65.22 59.09 34.55 44.10 57.83 77.17 102.86 126.49
62.02 - 68.41 56.45 - 61.86 32.48 - 36.62 41.95 - 46.25 54.44 - 61.22 72.66 - 81.67 97.24 - 108.49 115.33 - 137.65
6-11 1031 0.48 100.76 92.75 55.23 73.50 93.96 117.21 145.48 172.35
95.42 - 106.09 88.83 - 96.85 51.14 - 59.33 69.95 - 77.05 89.61 - 98.31 110.27 - 124.16 136.07 - 154.89 154.64 - 190.07
12-19 982 0.00 59.69 54.54 32.97 40.65 53.65 69.49 89.50 110.10
54.63 - 64.76 51.05 - 58.26 30.85 - 35.09 38.39 - 42.91 49.78 - 57.53 64.17 - 74.81 77.65 - 101.36 92.41 - 127.78
20-39 1165 0.77 59.40 54.26 32.49 41.07 52.46 70.03 95.69 105.82
55.86 - 62.94 51.23 - 57.47 29.80 - 35.18 38.34 - 43.80 49.10 - 55.81 64.61 - 75.46 85.68 - 105.70 89.37 - 122.28
40-59 1218 0.74 63.47 57.86 33.43 44.06 57.11 74.72 96.18 115.77
59.76 - 67.18 54.62 - 61.30 30.57 - 36.28 41.28 - 46.83 53.31 - 60.90 70.14 - 79.30 89.66 - 102.69 104.13 - 127.41
60-79 1083 0.18 67.72 62.58 39.22 47.96 62.20 79.31 103.88 119.86
64.13 - 71.31 59.36 - 65.98 36.16 - 42.27 44.44 - 51.48 58.85 - 65.55 75.68 - 82.94 94.94 - 112.81 108.00 - 131.72
Females
Total,
age 6-79
2826 0.67 68.41 62.09 36.45 46.32 62.19 81.02 105.71 128.41
65.27 - 71.54 59.23 - 65.09 34.47 - 38.43 43.71 - 48.93 58.89 - 65.48 76.08 - 85.97 101.90 - 109.52 122.68 - 134.13
6-11 509 0.59 100.11 90.56 51.82 70.48 89.84 118.35 146.65 179.69
92.65 - 107.57 85.55 - 95.86 46.62 - 57.02 65.32 - 75.64 83.96 - 95.72 107.85 - 128.85 131.15 - 162.14 145.77 - 213.62
12-19 478 0.00 57.06 53.02 32.96 40.26 52.11 66.94 85.72 107.42
52.11 - 62.01 49.10 - 57.25 30.37 - 35.54 37.90 - 42.61 46.75 - 57.47 60.26 - 73.63 76.11 - 95.34 88.06 - 126.79
20-39 653 0.92 62.85 57.72 36.40 44.30 55.51 72.94 100.24 113.30
58.13 - 67.56 53.86 - 61.86 34.15 - 38.65 40.66 - 47.94 51.10 - 59.92 66.46 - 79.41 89.41 - 111.08 92.95 - 133.65
40-59 644 1.24 67.17 60.96 35.12 45.22 63.26 80.12 100.35 121.22
62.84 - 71.51 57.21 - 64.96 31.03 - 39.22 41.59 - 48.85 59.04 - 67.49 71.83 - 88.40 90.21 - 110.50 98.04 - 144.41
60-79 542 0.37 74.65 69.12 43.00 54.30 67.87 87.37 113.01 135.99
71.10 - 78.20 65.80 - 72.61 39.87 - 46.12 50.59 - 58.01 63.96 - 71.79 81.64 - 93.09 103.68 - 122.35 121.33 - 150.66
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.11 Uranium (CASRN 7440-61-1)

Uranium (U) occurs naturally in variable, yet small amounts in rock, soil, water, and air. In its pure form, uranium is a silvery-white, lustrous, weakly radioactive metal that comprises approximately 0.0003% of the Earth's crust. Natural uranium is found in the environment in three radioactive isotope forms: uranium 238 (238U), uranium 235 (235U) and uranium 234 (234U) (WHO, 2003). Uranium is not a stable element but undergoes radioactive decay, producing radioactive products as well as alpha, beta, and gamma radiation. In its natural form, uranium is only weakly radioactive.

In addition to natural sources, uranium is released through human activities such as uranium mining and processing, which creates mill tailings (ATSDR, 1999; US EPA, 2002). This uranium can combine with other chemicals in the environment to form other uranium compounds with potentially higher water solubility. Canada is the world's leading producer of uranium and accounts for approximately one-third of total global output (NRCan, 2006). Approximately 15% of Canada's electricity derives from uranium, via nuclear power.

Uranium 235 is used primarily as a fuel in nuclear power reactors, but can also be a component of nuclear weapons. Due to its high density, depleted uranium (DU), which has low radioactivity, is used for military ammunition and armour-penetrating military ordnance. Civilian uses may include aviation guidance devices, radiation shielding material for medical purposes, chemical catalysts, and dentistry. Uranium dioxide is used to extend the life of incandescent lamps, and small amounts of other uranium compounds are used for photographic toning solution, as well as stains and dyes for leather, wood, and wool (CCME, 2007; US EPA, 2002).

Due to its natural abundance in the environment, as well as its various anthropogenic uses, humans are exposed to uranium on a regular basis. Uranium intake is primarily through the ingestion of food, although drinking water and house dust can also be significant sources (CCME, 2007). The concentration of uranium in drinking water will depend on the source of the water; most surface water sources have concentrations less than 1 µg/L (CCME, 2007); however, some groundwater wells in Canada have uranium concentrations up to several hundred μg/L (Health Canada, 1995). Uranium can also be present in household dust particles with reported concentrations ranging from 0.29 to 1.33 mg/kg, and with a geometric mean of 0.55 mg/kg, as reported in a study of Ottawa, Ontario, residences (Rasmussen et al., 2001). The background intake of uranium by the general Canadian population has been estimated to range from 0.023 µg/kg body weight/day for adults to 0.078 µg/kg body weight/day for toddlers (7 months to 4 years) (CCME, 2007). The intake was determined to be primarily through ingestion of food, although soil ingestion was also a significant source of exposure for toddlers.

Following ingestion, uranium rapidly appears in the bloodstream; it is then also cleared rapidly from the bloodstream. Absorption of uranium compounds from oral ingestion is less efficient than from inhalation, as most uranium compounds are not readily absorbed by the gastrointestinal tract; the vast majority will be excreted through the feces and a smaller amount in urine within a few days (ATSDR, 1999). Following inhalation, insoluble uranium compounds can remain in the lungs for years, while soluble forms enter the blood stream where they become concentrated in the bones and kidneys (CCME, 2007). The most common test for uranium exposure is through urine, as traces can remain for months after heavy exposure, although these tests are less accurate for low exposure levels (ATSDR, 1999). Other possible methods to determine if an individual has been exposed include testing blood and hair and measuring radiation levels within the body or on the skin.

Uranium can have health effects due to both its chemical toxicity and the toxicity of the radionuclides released. Because uranium is only weakly radioactive, health effects due to radioactivity, such as carcinogenicity, are generally only observed at much higher levels than those that can result in chemical toxicity. Chemical toxicity effects are the same regardless of isotopic composition (e.g., depleted uranium versus natural uranium) (Health Canada, 2004). Background levels of uranium have not been shown to cause harmful health effects through either ingestion or inhalation (CCME, 2007; ATSDR, 1999); however, exposure to higher levels in some occupational settings has been associated with damage to bones and kidneys. The health risks from exposure to natural or depleted uranium have been shown to be related more to dosage than to duration of exposure (CCME, 2007). Health Canada (2001) has classified uranium as Group V - inadequate data for evaluation of carcinogenicity; chemical carcinogenicity of uranium has been observed only from inhalation of highly insoluble or enriched uranium compounds and not from oral exposure. The International Agency for Research on Cancer (IARC, 2001) determined that there was inadequate evidence in humans and limited evidence in laboratory animals for carcinogenicity of natural uranium. These evaluations consider only potential chemical carcinogenicity; radiation is considered carcinogenic.

Health Canada (2001) has established a tolerable daily intake (TDI) for uranium of 0.60 µg/kg body weight/day. A Guideline for Canadian Drinking Water Quality of 0.020 mg/L (20 µg/L) has been established, considering both the toxicity and the availability of treatment technologies (Health Canada, 2001).

Uranium was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L in blood and as both µg/L and µg/g creatinine in urine (Tables 8.1.11a, 8.1.11b, 8.1.11c). Finding a measurable amount of uranium in blood or urine is an indicator of exposure to uranium and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for blood and urinary levels of uranium in the Canadian population.

Table 8.1.11a
Uranium - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5304 93.02 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
6-11 905 92.71 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
12-19 941 93.94 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
20-39 1162 91.14 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01 <LOD - 0.01
40-59 1217 92.77 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
<LOD - 0.01
60-79 1079 94.81 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
Males 
Total,
age 6-79
2569 92.99 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
6-11 457 93.65 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
12-19 489 93.87 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
<LOD - 0.01
20-39 511 91.59 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
40-59 575 91.48 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
60-79 537 94.60 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
Females
Total,
age 6-79
2735 93.05 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
6-11 448 91.74 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
12-19 452 94.03 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
20-39 651 90.78 -- -- <LOD <LOD <LOD <LOD 0.01 0.01
<LOD - 0.01 <LOD - 0.01
40-59 642 93.93 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
<LOD - 0.01
60-79 542 95.02 -- -- <LOD <LOD <LOD <LOD <LOD 0.01
<LOD - 0.01
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.11b
Uranium - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5491 87.05 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.01 0.01 - 0.02
6-11 1034 89.36 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.01 0.01 - 0.02
12-19 983 83.11 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
0.01 - 0.02 0.02 - 0.03
20-39 1169 87.43 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.01 <LOD - 0.03
40-59 1223 86.26 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.01 0.01 - 0.02
60-79 1082 88.91 -- -- <LOD <LOD <LOD <LOD <LOD 0.02
0.01 - 0.02
Males 
Total,
age 6-79
2662 85.88 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.02 0.01 - 0.03
6-11 524 89.50 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.01 <LOD - 0.03
12-19 505 80.20 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
0.01 - 0.02 0.01 - 0.03
20-39 514 87.35 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.02 <LOD - 0.03
40-59 578 83.39 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
0.01 - 0.01 0.01 - 0.02
60-79 541 88.91 -- -- <LOD <LOD <LOD <LOD <LOD 0.02
0.01 - 0.02
Females
Total,
age 6-79
2829 88.16 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.01 0.01 - 0.02
6-11 510 89.22 -- -- <LOD <LOD <LOD <LOD 0.01 0.01
<LOD - 0.01 0.01 - 0.02
12-19 478 86.19 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
0.01 - 0.02 0.02 - 0.03
20-39 655 87.48 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.02 <LOD - 0.03
40-59 645 88.84 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.01 0.01 - 0.02
60-79 541 88.91 -- -- <LOD <LOD <LOD <LOD 0.01 0.02
<LOD - 0.02 <LOD - 0.02
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.11c
Uranium (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5478 87.26 -- -- <LOD <LOD <LOD <LOD 0.02 0.03
<LOD - 0.02 0.03 - 0.03
6-11 1031 89.62 -- -- <LOD <LOD <LOD <LOD 0.02 0.04
<LOD - 0.03 0.03 - 0.05
12-19 982 83.20 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
0.01 - 0.02 0.02 - 0.03
20-39 1165 87.73 -- -- <LOD <LOD <LOD <LOD 0.02 0.03
<LOD - 0.02 <LOD - 0.04
40-59 1218 86.62 -- -- <LOD <LOD <LOD <LOD 0.02 0.03
<LOD - 0.03 0.03 - 0.03
60-79 1082 88.91 -- -- <LOD <LOD <LOD <LOD <LOD 0.03
0.02 - 0.04
Males 
Total,
age 6-79
2653 86.17 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
<LOD - 0.02 0.02 - 0.03
6-11 522 89.85 -- -- <LOD <LOD <LOD <LOD 0.02 0.04
<LOD - 0.03 <LOD - 0.06
12-19 504 80.36 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
0.01 - 0.02 0.01 - 0.03
20-39 512 87.70 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
<LOD - 0.02 <LOD - 0.04
40-59 574 83.97 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
0.01 - 0.02 0.02 - 0.03
60-79 541 88.91 -- -- <LOD <LOD <LOD <LOD <LOD 0.02
0.01 - 0.02
Females
Total,
age 6-79
2825 88.28 -- -- <LOD <LOD <LOD <LOD 0.02 0.04
<LOD - 0.03 0.03 - 0.04
6-11 509 89.39 -- -- <LOD <LOD <LOD <LOD 0.02 0.03
<LOD - 0.03 0.02 - 0.05
12-19 478 86.19 -- -- <LOD <LOD <LOD <LOD 0.02 0.02
0.01 - 0.02 0.02 - 0.03
20-39 653 87.75 -- -- <LOD <LOD <LOD <LOD 0.02 0.03
<LOD - 0.03 <LOD - 0.04
40-59 644 88.98 -- -- <LOD <LOD <LOD <LOD 0.03 0.04
<LOD - 0.03 0.03 - 0.05
60-79 541 88.91 -- -- <LOD <LOD <LOD <LOD 0.03 0.04
<LOD - 0.04 <LOD - 0.05
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.12 Vanadium (CASRN 7440-62-2)

Vanadium (V) is a naturally occurring element found in the Earth's crust and is present in iron ores, phosphate rock, and crude oil deposits. Vanadium is usually found combined with other elements and can exist in six different oxidation states, acting as either a metal or non-metal. Some common vanadium compounds include carnotite, patronite, roscoelite, and vanadinite (CCME, 1995; ATSDR, 1992). Vanadium is generally associated with organic matter; as a result, vanadium is found in crude oil and various refined petroleum products, particularly heavy fuel oil. Lesser natural sources of vanadium include erosion and weathering of rock-bearing minerals, marine aerosols, and volcanic emissions.

The bulk of vanadium, as vanadium oxides, used in Canada is imported from other countries, although there is some recovery from crude oil and petroleum products (NRCan, 2010; CCME, 1995). Vanadium is mainly used as an alloy additive in the production of various steels to increase strength, hardness, wear-resistance, and ductility. Vanadium pentoxide is used to produce ferrovanadium alloys for aircraft engines and nonferrous (titanium) alloys. In addition, vanadium is used in the manufacture of maleic anhydride, phthalic anhydride and sulphuric acid, as a catalyst in multiple processes such as petroleum cracking, and in the production of pesticides, dyes, inks, and pigments. Vanadium compounds are also used in mercury vapour lamps to modify the colour, and may be found in some paints, varnishes, corrosion inhibitors, and photographic developers (CCME, 1995; ATSDR, 1992).

The releases of vanadium oxide into the Canadian environment are mainly atmospheric emissions from various industrial activities. The major anthropogenic sources of vanadium oxide are the burning of fossil fuels and emissions from oil refineries, produced during the catalytic processing of oil (Tullar and Suffet 1975; Lin and Chiu 1995). Petroleum coke, which contains even higher vanadium levels than either petroleum or coal, is increasingly being used as a full or partial replacement for coal in electrical power generation (Scott and Thomas 2007).

Due to its natural presence in the environment and releases from the combustion of fossil fuels, the general population is exposed to vanadium daily. The main source of vanadium for the general adult population is through food, although exposure can also come from air, drinking water, soil, and household dust (CCME, 1995). Grains and grain products have been estimated to contribute 13-30% of the vanadium in adult diets, while canned apple juice and cereals were the major contributors in the diets of infants and toddlers (Pennington & Jones, 1987). Soil is a major source of exposure for children under 11 years of age (Environment Canada & Health Canada, 2010). Vanadium was also used as a supplement, particularly for diabetic patients, and this use can account for much of the exposure to vanadium in certain people (Pennington & Jones, 1987). Vanadium is believed to have beneficial effects at low doses; however, its role in the body remains unclear (IOM, 2001). Health Canada (2005) has concluded that there is insufficient data to establish an estimated average requirement or adequate intake. The Health Canada multi-vitamin/mineral monograph does not allow vanadium oxide as a source of vanadium in natural health products (Health Canada, 2007).

Vanadium can be absorbed following inhalation, oral or dermal exposure, with dermal absorption being less efficient than inhalation or oral absorption. Long-term distribution of vanadium in the body is independent of the route of exposure, with bones being the main reservoir for vanadium. Ingested vanadium is mainly excreted through the feces, and the kidneys are the main route for elimination of absorbed vanadium (ACGIH, 2001). Very little of the absorbed vanadium is retained in the body; absorption of ingested vanadium is less than 5%, thus most ingested vanadium is found in the feces (IOM, 2001). As such, urinary vanadium is a biomarker of exposure to absorbed vanadium and vanadium-related compounds (e.g., vanadium oxide) (ACGIH, 2001) and the relationship between external exposure and urine concentrations is variable (ACGIH, 2001; ATSDR, 1992). Urinary vanadium provides only a qualitative indication of external exposure (ATSDR, 1992).

There is limited information regarding the effects of low-level exposure to vanadium. There is human evidence of mild gastrointestinal effects and hematological effects, such as anemia, following ingestion of vanadium compounds. Renal toxicity has been observed in animals following ingestion of vanadium compounds, but these effects have not been seen in humans (IOM, 2001). Workers chronically exposed to vanadium dusts in factories reported slight to moderate eye irritation (ATSDR, 1992). Acute inhalation exposure to high concentrations of vanadium has been associated with respiratory irritation (ATSDR, 1992). The International Agency for Research on Cancer (IARC) recently evaluated the carcinogenicity of vanadium pentoxide. It classified this substance as a possible human carcinogen (Group 2B), based on inadequate human data but sufficient evidence of respiratory cancers in rodent inhalation studies (IARC, 2006). Health Canada and Environment Canada are jointly reviewing and assessing chemical substances as part of the Chemicals Management Plan under the Canadian Environmental Protection Act, 1999. Vanadium oxide (CASRN 1314-62-1) was identified as a high priority substance under the Chemicals Management Plan and a draft assessment was published in March 2010 (Government of Canada, 2009; Environment Canada and Health Canada, 2010).

Health Canada (2005) has adopted Tolerable Upper Intake Levels (UL) developed by the Institute of Medicine (IOM) for vanadium that are based on renal toxicity as the critical adverse effect. The ULs for vanadium are 1.8 mg/day for adults over 19 years of age (IOM, 2001).

Vanadium was measured in the urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L urine and µg/g creatinine (Tables 8.1.12a, 8.1.12b). Finding a measurable amount of vanadium in urine is an indicator of exposure to vanadium and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for urinary levels of vanadium in the Canadian population.

Table 8.1.12a
Vanadium - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 90.37 -- -- <LOD <LOD <LOD <LOD 0.10 0.15
<LOD - 0.12 0.13 - 0.16
6-11 1034 94.68 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
12-19 983 92.98 -- -- <LOD <LOD <LOD <LOD <LOD 0.14
0.12 - 0.17
20-39 1169 89.56 -- -- <LOD <LOD <LOD <LOD 0.10 0.14
<LOD - 0.12 0.12 - 0.17
40-59 1223 88.72 -- -- <LOD <LOD <LOD <LOD 0.11 0.15
<LOD - 0.13 0.13 - 0.17
60-79 1083 86.61 -- -- <LOD <LOD <LOD <LOD 0.11 0.16
<LOD - 0.13 0.13 - 0.19
Males 
Total,
age 6-79
2662 88.32 -- -- <LOD <LOD <LOD <LOD 0.12 0.17
0.10 - 0.13 0.15 - 0.19
6-11 524 95.04 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
12-19 505 92.87 -- -- <LOD <LOD <LOD <LOD <LOD 0.11
<LOD - 0.17
20-39 514 87.74 -- -- <LOD <LOD <LOD <LOD 0.11 0.16
<LOD - 0.14 0.13 - 0.19
40-59 578 84.60 -- -- <LOD <LOD <LOD <LOD 0.12 0.20
0.11 - 0.14 0.14 - 0.27
60-79 541 82.07 -- -- <LOD <LOD <LOD <LOD 0.14 0.19
0.11 - 0.17 0.13 - 0.25
Females
Total,
age 6-79
2830 92.30 -- -- <LOD <LOD <LOD <LOD <LOD 0.13
0.11 - 0.14
6-11 510 94.31 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
12-19 478 93.10 -- -- <LOD <LOD <LOD <LOD 0.12 0.16
<LOD - 0.16 0.12 - 0.20
20-39 655 90.99 -- -- <LOD <LOD <LOD <LOD <LOD 0.13
<LOD - 0.17
40-59 645 92.40 -- -- <LOD <LOD <LOD <LOD <LOD 0.12
<LOD - 0.15
60-79 542 91.14 -- -- <LOD <LOD <LOD <LOD <LOD 0.11
<LOD - 0.14
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.12b
Vanadium (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 90.58 -- -- <LOD <LOD <LOD <LOD 0.21 0.30
<LOD - 0.23 0.26 - 0.33
6-11 1031 94.96 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
12-19 982 93.08 -- -- <LOD <LOD <LOD <LOD <LOD 0.20
0.16 - 0.23
20-39 1165 89.87 -- -- <LOD <LOD <LOD <LOD 0.19 0.30
<LOD - 0.23 0.22 - 0.37
40-59 1218 89.08 -- -- <LOD <LOD <LOD <LOD 0.23 0.31
<LOD - 0.26 0.27 - 0.34
60-79 1083 86.61 -- -- <LOD <LOD <LOD <LOD 0.21 0.31
<LOD - 0.24 0.26 - 0.35
Males 
Total,
age 6-79
2653 88.62 -- -- <LOD <LOD <LOD <LOD 0.17 0.25
0.15 - 0.19 0.20 - 0.30
6-11 522 95.40 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
12-19 504 93.06 -- -- <LOD <LOD <LOD <LOD <LOD 0.18
<LOD - 0.24
20-39 512 88.09 -- -- <LOD <LOD <LOD <LOD 0.17 0.26
<LOD - 0.22 0.15 - 0.37
40-59 574 85.19 -- -- <LOD <LOD <LOD <LOD 0.18 0.26
0.16 - 0.19 0.21 - 0.31
60-79 541 82.07 -- -- <LOD <LOD <LOD <LOD 0.16 0.21
0.14 - 0.19 0.17 - 0.24
Females
Total,
age 6-79
2826 92.43 -- -- <LOD <LOD <LOD <LOD <LOD 0.33
0.28 - 0.38
6-11 509 94.50 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
12-19 478 93.10 -- -- <LOD <LOD <LOD <LOD 0.15 0.21
<LOD - 0.20 0.14 - 0.29
20-39 653 91.27 -- -- <LOD <LOD <LOD <LOD <LOD 0.34
<LOD - 0.45
40-59 644 92.55 -- -- <LOD <LOD <LOD <LOD <LOD 0.34
<LOD - 0.45
60-79 542 91.14 -- -- <LOD <LOD <LOD <LOD <LOD 0.33
<LOD - 0.42
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.1.13 Zinc (CASRN 7440-66-6)

Zinc (Zn) is one of the more common naturally occurring elements, and comprises approximately 0.004% of the Earth's crust (Browning, 1969). It is a lustrous, bluish-white, relatively soft metal in its pure state and can exist in a divalent oxidation state in various inorganic and organic compounds, which can be transformed by sunlight, water, and air. The most common zinc ore is sphalerite (ZnS), which often exists with the sulphides of other metallic elements, for example, lead, copper, cadmium, and iron (US EPA, 1976). Zinc is also found as calamine (ZnCO3) in carbonate sediments; other forms of zinc are usually products of the oxidation of sphalerite (US EPA, 1976; Hem, 1970). Zinc is an essential nutrient required for the maintenance of good health.

Canada is one of the major producers and exporters of zinc globally (Health Canada, 1987; Environment Canada, 1999). Zinc is mainly used for galvanizing other metal products, such as iron and steel, in order to prevent corrosion. Other principal uses include the production of alloys, such as brass and bronze, and the manufacture of dry-cell batteries. Zinc is also used in paints, preservatives, dyes, pesticides, various cosmetic and pharmaceutical products; in the manufacture of rayons, yarns, inks, matches, tires, and other rubber products; for cementing metals in metallurgical processing; and in ornamental work (Health Canada, 1987; Environment Canada, 1999). Zinc compounds can also be found in products such as vitamin or mineral supplements, sunscreens, deodorants, and anti-dandruff shampoos.

Due to its natural abundance and prominent use in industry, everyone is exposed to small amounts of zinc. The general population is primarily exposed to zinc at low levels through the ingestion of food. Increased exposure may occur in drinking water from pipes and fittings leaching zinc. Workers in certain occupational settings, such as mining, smelting, welding, or the manufacture of zinc alloys and galvanized metals, may also be exposed to higher amounts of zinc (ATSDR, 2005). Concentrations of zinc in serum and urine are believed to increase after exposure to high doses. Serum zinc levels are commonly used as indicators of population zinc status (Hess et al., 2007). Hair and nail samples have also been suggested as having potential value for monitoring longer-term exposure (ATSDR, 2005).

Following ingestion, zinc is absorbed via the gastrointestinal tract and then transported to various tissues and organs. Between 20 and 30% of dietary zinc is absorbed, with enhanced absorption occurring under conditions of zinc deficiency (Department of National Health and Welfare, 1983). Over 85% of the total body zinc is found in skeletal muscle and bone (IOM, 2001). The primary route of excretion from the body is via the gastrointestinal tract, and this includes unabsorbed dietary zinc, a small amount from sloughing of intestinal epithelial cells, and zinc from biliary and pancreatic origin. Under normal circumstances, about 0.5 mg of zinc may be lost in perspiration with an equal amount lost in daily urine (Prasad, 1983).

Zinc is an essential trace element in humans, forming a component of many metalloenzymes and other substances in the body. It aids in connective tissue formation, the maintenance of healthy skin, immune system functioning, and the metabolism of carbohydrates, fats, and proteins (Health Canada, 1987; Environment Canada, 1999; Health Canada, 2007). Insufficient zinc intake may lead to dermatitis, anorexia, reduced growth, poor healing of wounds, reduced reproductive ability, reduced mental function, and impairment of the immune system (ATSDR, 2005). The Recommended Dietary Allowance (RDA) for Canadians is 2 mg/day for young infants, 3-7 mg/day for children to age 13, and from the age of 14, 11 mg/day for males and 8 mg/day for females (Health Canada, 2005).

Exposure to high levels of zinc can affect health. Acute zinc toxicity is usually the result of taking excess vitamin or mineral supplements or drinking acidic beverages stored for long periods of time in galvanized containers (WHO, 2003). Large doses of zinc can cause stomach cramps, nausea, and vomiting (ATSDR, 2005). Ingesting high levels of zinc can inhibit absorption of copper into the blood stream (WHO, 2003; US EPA, 2005) and chronic zinc toxicosis, manifesting as a copper deficiency, can occur. Effects of inhaled zinc are generally limited to the respiratory tract and vary depending on the specific chemical composition (ATSDR, 2005). Inhalation of large quantities of zinc dust or fumes, such as in occupational settings, can result in a reversible short-term condition lasting a few days known as "metal fume fever," which begins with a dry throat and coughing and leads to chest pain, coughing, and shortness of breath.

Health Canada (2005) has adopted Tolerable Upper Intake Levels (UL) developed by the Institute of Medicine (IOM) for zinc, which account for both its essentiality and its potential toxicity. The ULs for zinc are 4 mg/day for infants 0-6 months old, 5 mg/day for infants 7-12 months old, 7 mg/day for children 1-3 years old, 12 mg/day for children 4-8 years old, 23 mg/day for children 9-13 years old, 34 mg/day for adolescents 14-18 years old, and 40 mg/day for adults (IOM, 2001). Health Canada (1987) has established an aesthetic objective for drinking water of ≤5.0 mg/L based on taste; this guideline was also deemed protective of adverse health effects.

Health Canada and Environment Canada assessed the metals (largely in the form of particulates) copper, zinc, nickel, lead, cadmium, chromium, and arsenic, contained in emissions from zinc plants, and concluded they were of concern to the environment and to human health (Environment Canada & Health Canada, 2001).

In a study carried out in British Columbia on non-smoking adults aged 30-65, the geometric mean and 95th percentile concentrations of zinc in urine were 285.43 µg/g creatinine and 607.83 µg/g creatinine, respectively (Clark et al., 2007).

Zinc was measured in the blood and urine of all participants aged 6-79 years in the Canadian Health Measures Survey and is presented as µg/L in blood and as both µg/L and µg/g creatinine in urine (Tables 8.1.13a, 8.1.13b, 8.1.13c). Finding a measurable amount of zinc in blood or urine is an indicator of exposure to zinc and does not necessarily mean that an adverse health effect will occur. Since it is an essential nutrient, its presence is expected. These data provide reference ranges for blood and urinary levels of zinc in the Canadian population.

Table 8.1.13a
Zinc - Arithmetic and geometric means, and selected percentiles of blood concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5319 0.00 6.44 6.37 5.23 5.80 6.42 7.06 7.61 7.91
6.35 - 6.53 6.28 - 6.46 5.12 - 5.34 5.73 - 5.87 6.35 - 6.49 6.96 - 7.16 7.50 - 7.72 7.79 - 8.03
6-11 910 0.00 5.29 5.24 4.42 4.78 5.26 5.73 6.18 6.51
5.17 - 5.40 5.12 - 5.36 4.27 - 4.56 4.62 - 4.94 5.12 - 5.40 5.63 - 5.83 6.03 - 6.34 6.37 - 6.65
12-19 945 0.00 6.03 5.96 4.94 5.45 6.01 6.54 7.15 7.44
5.93 - 6.13 5.86 - 6.07 4.75 - 5.13 5.34 - 5.55 5.84 - 6.17 6.44 - 6.64 7.07 - 7.23 7.23 - 7.64
20-39 1165 0.00 6.48 6.41 5.34 5.83 6.44 7.06 7.58 7.87
6.37 - 6.58 6.31 - 6.52 5.17 - 5.51 5.72 - 5.94 6.35 - 6.54 6.94 - 7.18 7.45 - 7.72 7.65 - 8.09
40-59 1220 0.00 6.59 6.54 5.53 6.03 6.53 7.11 7.66 7.97
6.49 - 6.70 6.43 - 6.65 5.36 - 5.70 5.91 - 6.15 6.38 - 6.68 6.99 - 7.24 7.54 - 7.78 7.73 - 8.21
60-79 1079 0.00 6.75 6.68 5.65 6.18 6.72 7.31 7.82 8.11
6.63 - 6.86 6.57 - 6.79 5.49 - 5.82 6.06 - 6.30 6.57 - 6.87 7.15 - 7.48 7.67 - 7.96 7.96 - 8.25
Males 
Total,
age 6-79
2576 0.00 6.68 6.61 5.39 6.09 6.72 7.32 7.77 8.10
6.57 - 6.78 6.50 - 6.71 5.32 - 5.45 6.00 - 6.17 6.59 - 6.86 7.20 - 7.45 7.65 - 7.90 7.91 - 8.29
6-11 459 0.00 5.21 5.17 4.39 4.68 5.14 5.64 6.15 6.39
5.06 - 5.36 5.02 - 5.32 4.22 - 4.56 4.53 - 4.83 4.96 - 5.32 5.50 - 5.78 5.92 - 6.37 6.14 - 6.65
12-19 489 0.00 6.14 6.06 4.88 5.44 6.11 6.86 7.26 7.88
6.00 - 6.28 5.92 - 6.21 4.60 - 5.16 5.29 - 5.59 5.88 - 6.34 6.66 - 7.06 7.06 - 7.45 7.42 - 8.33
20-39 514 0.00 6.77 6.72 5.66 6.21 6.78 7.38 7.76 7.98
6.63 - 6.91 6.58 - 6.86 5.32 - 5.99 6.04 - 6.38 6.60 - 6.95 7.25 - 7.51 7.55 - 7.98 7.69 - 8.27
40-59 577 0.00 6.91 6.86 5.93 6.39 6.86 7.43 7.83 8.26
6.76 - 7.06 6.71 - 7.02 5.75 - 6.11 6.25 - 6.53 6.67 - 7.05 7.24 - 7.62 7.60 - 8.07 7.93 - 8.59
60-79 537 0.00 7.00 6.94 5.95 6.42 6.95 7.54 7.95 8.25
6.87 - 7.12 6.82 - 7.06 5.84 - 6.05 6.29 - 6.55 6.78 - 7.12 7.36 - 7.73 7.83 - 8.07 8.04 - 8.46
Females
Total,
age 6-79
2743 0.00 6.19 6.13 5.14 5.63 6.19 6.72 7.19 7.58
6.11 - 6.28 6.05 - 6.22 5.02 - 5.26 5.53 - 5.73 6.10 - 6.27 6.61 - 6.83 7.10 - 7.29 7.43 - 7.74
6-11 451 0.00 5.36 5.32 4.44 4.90 5.35 5.81 6.28 6.57
5.24 - 5.49 5.19 - 5.45 4.17 - 4.70 4.72 - 5.08 5.22 - 5.48 5.68 - 5.95 6.04 - 6.52 6.41 - 6.73
12-19 456 0.00 5.90 5.86 5.02 5.44 5.90 6.37 6.81 7.03
5.80 - 6.00 5.75 - 5.97 4.85 - 5.19 5.33 - 5.56 5.74 - 6.07 6.24 - 6.50 6.61 - 7.01 6.83 - 7.23
20-39 651 0.00 6.18 6.12 5.12 5.58 6.18 6.67 7.12 7.51
6.03 - 6.33 5.97 - 6.26 4.91 - 5.32 5.44 - 5.73 5.98 - 6.38 6.53 - 6.80 6.98 - 7.27 7.03 - 7.99
40-59 643 0.00 6.28 6.24 5.29 5.75 6.26 6.73 7.22 7.53
6.17 - 6.40 6.12 - 6.35 5.10 - 5.49 5.64 - 5.86 6.14 - 6.38 6.57 - 6.89 7.07 - 7.37 7.35 - 7.72
60-79 542 0.00 6.52 6.46 5.44 5.96 6.46 7.01 7.59 7.97
6.37 - 6.66 6.32 - 6.60 5.23 - 5.64 5.76 - 6.15 6.35 - 6.58 6.85 - 7.18 7.37 - 7.81 7.61 - 8.33
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.13b
Zinc - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/L) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5492 0.78 389.50 254.02 67.64 136.98 274.33 524.69 835.11 1087.90
372.15 - 406.84 238.43 - 270.63 58.18 - 77.10 121.05 - 152.90 259.41 - 289.25 499.26 - 550.12 789.83 - 880.38 1027.88 - 1147.93
6-11 1034 0.19 388.46 293.15 98.41 189.91 326.86 519.34 752.89 860.12
354.62 - 422.31 260.64 - 329.70 74.26 - 122.56 165.54 - 214.28 284.54 - 369.18 470.86 - 567.81 682.83 - 822.95 788.47 - 931.77
12-19 983 0.10 541.80 396.80 126.10 228.41 454.02 729.80 1022.99 1370.65
490.58 - 593.03 364.64 - 431.79 103.18 - 149.03 197.48 - 259.34 417.17 - 490.87 683.87 - 775.74 878.51 - 1167.46 1085.36 - 1655.95
20-39 1169 1.20 341.28 218.60 57.22 119.22 224.21 456.87 763.54 1039.90
315.72 - 366.84 198.90 - 240.25 44.61 - 69.84 97.03 - 141.40 189.70 - 258.72 408.40 - 505.34 681.11 - 845.98 902.14 - 1177.66
40-59 1223 1.39 372.49 234.12 59.19 119.50 249.63 497.64 818.13 1131.81
342.68 - 402.29 214.57 - 255.44 47.15 - 71.22 101.77 - 137.24 221.13 - 278.12 440.06 - 555.22 648.43 - 987.82 971.11 - 1292.51
60-79 1083 0.83 411.29 275.36 82.44 154.56 293.09 547.78 866.66 1100.93
382.07 - 440.51 256.11 - 296.05 60.51 - 104.38 131.51 - 177.61 269.64 - 316.54 506.22 - 589.34 758.06 - 975.27 977.48 - 1224.38
Males 
Total,
age 6-79
2662 0.34 461.94 326.35 103.22 189.43 351.41 598.80 981.47 1225.41
445.14 - 478.73 309.83 - 343.75 90.68 - 115.76 172.28 - 206.57 329.55 - 373.28 569.89 - 627.71 920.98 - 1041.96 1144.01 - 1306.82
6-11 524 0.38 387.61 295.56 105.06 199.21 329.10 519.20 744.35 834.04
340.39 - 434.83 244.90 - 356.70 69.99 - 140.13 164.40 - 234.02 259.57 - 398.64 446.97 - 591.42 652.79 - 835.91 774.92 - 893.16
12-19 505 0.00 585.00 450.81 160.77 270.56 481.77 748.34 1089.70 1384.66
532.21 - 637.79 411.00 - 494.49 136.82 - 184.72 234.14 - 306.98 433.77 - 529.77 705.33 - 791.35 929.08 - 1250.32 1115.86 - 1653.47
20-39 514 0.39 431.81 294.09 84.58 154.95 307.62 572.85 947.98 1218.51
383.95 - 479.66 250.93 - 344.68 53.62 - 115.53 114.76 - 195.14 242.36 - 372.88 491.42 - 654.27 759.13 - 1136.82 1056.97 - 1380.05
40-59 578 0.52 456.47 317.86 95.76 187.55 349.03 574.18 986.86 1258.30
413.14 - 499.80 293.41 - 344.35 73.40 - 118.12 172.71 - 202.40 306.29 - 391.77 510.00 - 638.35 829.27 - 1144.45 945.54 - 1571.05
60-79 541 0.37 476.42 348.80 116.75 215.06 360.93 589.76 991.53 1162.98
423.12 - 529.71 313.37 - 388.23 90.93 - 142.57 196.65 - 233.46 318.60 - 403.27 492.47 - 687.05 853.14 - 1129.92 782.12 - 1543.85
Females
Total,
age 6-79
2830 1.20 317.15 197.78 51.06 102.41 210.14 423.23 685.19 936.85
291.83 - 342.47 180.16 - 217.13 44.72 - 57.40 84.83 - 120.00 192.04 - 228.24 385.27 - 461.20 630.07 - 740.32 833.84 - 1039.86
6-11 510 0.00 389.36 290.62 92.62 183.45 324.31 520.08 761.99 925.23
352.47 - 426.25 264.18 - 319.71 73.27 - 111.98 155.42 - 211.48 289.38 - 359.24 464.19 - 575.97 651.59 - 872.40 782.31 - 1068.15
12-19 478 0.21 494.50 345.05 93.97 180.75 393.57 705.25 1004.23 1300.18
435.01 - 554.00 304.40 - 391.13 61.52 - 126.43 143.01 - 218.48 329.56 - 457.59 595.92 - 814.57 795.61 - 1212.85 869.44 - 1730.92
20-39 655 1.83 249.94 162.05 46.20 87.02 169.66 350.85 549.37 669.79
222.66 - 277.22 145.18 - 180.88 35.99 - 56.41 67.66 - 106.38 146.54 - 192.77 297.03 - 404.66 448.24 - 650.49 595.21 - 744.37
40-59 645 2.17 289.41 173.01 46.99 86.59 186.74 362.37 650.00 948.58
242.29 - 336.54 146.71 - 204.03 35.73 - 58.25 66.12 - 107.06 147.29 - 226.18 292.95 - 431.79 537.73 - 762.26 672.12 - 1225.05
60-79 542 1.29 351.46 221.60 58.60 120.15 225.91 501.97 715.69 938.49
317.68 - 385.23 191.27 - 256.75 41.41 - 75.79 83.43 - 156.88 186.39 - 265.44 423.11 - 580.83 649.42 - 781.96 754.99 - 1121.99
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.1.13c
Zinc (creatinine adjusted) - Arithmetic and geometric means, and selected percentiles of urine concentrations (μg/g creatinine) for the Canadian population aged 6-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 6-79
5479 0.78 376.88 307.11 132.01 204.85 323.01 482.54 667.09 847.45
367.01 - 386.74 296.99 - 317.57 123.37 - 140.66 194.70 - 214.99 313.88 - 332.14 462.56 - 502.52 637.53 - 696.64 812.52 - 882.39
6-11 1031 0.19 508.21 451.08 242.02 333.59 465.00 612.18 828.72 966.87
482.23 - 534.18 426.43 - 477.16 214.67 - 269.37 310.42 - 356.75 442.34 - 487.66 580.30 - 644.06 773.58 - 883.87 893.49 - 1040.24
12-19 982 0.10 401.99 345.37 166.20 244.88 360.37 515.23 669.15 835.32
379.16 - 424.83 321.96 - 370.48 144.16 - 188.24 220.64 - 269.13 336.61 - 384.13 493.14 - 537.32 606.02 - 732.29 738.01 - 932.64
20-39 1165 1.20 289.02 243.79 111.27 170.17 254.85 363.28 510.11 602.17
273.70 - 304.33 228.57 - 260.02 95.73 - 126.81 155.21 - 185.14 235.15 - 274.55 346.88 - 379.67 469.32 - 550.89 567.71 - 636.62
40-59 1218 1.40 370.79 299.94 129.51 198.61 321.91 471.57 662.08 824.95
349.38 - 392.20 283.82 - 316.99 114.98 - 144.04 187.87 - 209.36 298.47 - 345.35 426.00 - 517.14 610.78 - 713.39 763.25 - 886.66
60-79 1083 0.83 476.50 385.06 166.35 262.25 393.84 597.37 885.74 1078.79
452.55 - 500.46 361.61 - 410.02 133.65 - 199.05 230.99 - 293.50 366.42 - 421.27 555.22 - 639.53 840.83 - 930.65 974.99 - 1182.59
Males 
Total,
age 6-79
2653 0.34 379.64 321.99 148.40 224.95 331.39 486.82 649.38 814.21
365.76 - 393.51 308.01 - 336.59 130.65 - 166.15 207.77 - 242.14 314.75 - 348.02 459.38 - 514.26 619.45 - 679.32 772.52 - 855.90
6-11 522 0.38 502.40 448.14 237.86 335.61 464.89 616.58 812.03 910.75
463.47 - 541.34 419.58 - 478.65 214.59 - 261.13 313.06 - 358.16 433.86 - 495.93 563.64 - 669.52 736.22 - 887.85 827.78 - 993.71
12-19 504 0.00 431.20 379.89 200.29 274.39 388.97 543.41 673.26 857.96
403.54 - 458.85 351.76 - 410.26 170.69 - 229.88 249.22 - 299.57 357.23 - 420.70 518.24 - 568.58 581.98 - 764.55 741.98 - 973.93
20-39 512 0.39 310.59 268.98 129.24 187.20 275.21 384.91 545.74 612.03
286.06 - 335.12 245.69 - 294.48 109.44 - 149.03 162.48 - 211.91 229.26 - 321.16 345.99 - 423.82 476.42 - 615.07 574.90 - 649.15
40-59 574 0.52 366.97 312.79 147.54 210.84 326.66 449.92 645.30 743.35
343.80 - 390.15 297.78 - 328.56 134.94 - 160.15 190.04 - 231.64 306.49 - 346.82 409.48 - 490.36 573.87 - 716.73 643.79 - 842.92
60-79 541 0.37 444.38 367.83 170.60 243.30 375.49 558.60 835.16 1000.82
412.22 - 476.55 337.21 - 401.23 143.09 - 198.11 211.01 - 275.59 346.17 - 404.81 514.61 - 602.60 737.27 - 933.05 858.72 - 1142.92
Females
Total,
age 6-79
2826 1.20 374.12 292.96 117.51 186.15 311.88 478.30 696.74 885.78
358.22 - 390.03 280.41 - 306.08 105.54 - 129.49 170.87 - 201.44 292.40 - 331.36 450.44 - 506.16 647.07 - 746.41 809.45 - 962.11
6-11 509 0.00 514.32 454.20 242.23 328.49 464.72 610.85 833.79 1012.11
489.42 - 539.21 425.86 - 484.42 197.42 - 287.05 297.34 - 359.65 440.03 - 489.42 579.50 - 642.20 743.79 - 923.80 900.92 - 1123.30
12-19 478 0.21 370.10 311.25 149.65 199.84 308.65 472.12 657.23 769.12
344.44 - 395.77 289.58 - 334.55 131.99 - 167.30 160.00 - 239.67 289.07 - 328.23 419.99 - 524.26 579.28 - 735.18 684.97 - 853.27
20-39 653 1.84 267.27 220.78 94.46 150.41 229.69 342.71 468.71 575.71
243.29 - 291.26 203.16 - 239.94 83.79 - 105.14 141.15 - 159.67 207.34 - 252.05 305.53 - 379.89 397.81 - 539.60 490.28 - 661.15
40-59 644 2.17 374.56 287.80 110.09 182.12 303.24 496.20 711.46 904.62
341.24 - 407.87 261.44 - 316.82 88.68 - 131.49 148.70 - 215.54 262.47 - 344.02 446.64 - 545.76 630.00 - 792.91 640.34 - 1168.90
60-79 542 1.29 506.01 401.60 151.98 290.14 425.47 627.28 921.54 1125.33
469.41 - 542.61 372.05 - 433.48 91.69 - 212.28 248.21 - 332.07 385.81 - 465.12 591.96 - 662.60 821.27 - 1021.82 939.16 - 1311.50
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
References

8.2 Organochlorines

8.2.1 Aldrin (CASRN 309-00-2)

Aldrin is an organochlorine insecticide with the systematic name 1,2,3,4,10,10-hexachloro-1,4,4α,5,8,8α-hexahydro-1,4-endo,exo-5,8-dimethanonaphthalene, and the chemical formula C12H8Cl6. Aldrin is closely related to dieldrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4α,5,6,7,8,8α-octahydro-1,4-endo, exo-5,8-dimethanonaphthalene; chemical formula C12H8Cl6O), and may be converted to dieldrin in the environment or through metabolic processes in the human body (ATSDR, 2002).

Aldrin is a synthetic chemical that does not occur naturally in the environment. It was manufactured for use only in pesticide applications (both agricultural and non-agricultural) and is no longer produced or imported into North America (ATSDR, 2002; Health Canada, 1995).

Aldrin was primarily used as an insecticide on crops, such as corn and cotton, from the 1950s through the 1970s, as well as for domestic, forestry, and industrial use (ATSDR, 2002; Health Canada, 1995). Aldrin is a soil insecticide that works by contact and ingestion (Hayes, 1982). Registration and use of aldrin decreased significantly after the mid-1970s, although limited use for subterranean termite control continued until the mid-1980s (Health Canada, 1995). Aldrin and dieldrin were not registered for use in Canada after 1990 (Agriculture Canada, 1990).

Aldrin previously entered the environment from treated crops and from use by exterminators, and may still persist in soils where it was applied. Current sources include spills and leaks from waste sites, as well as redistribution to previously uncontaminated areas by processes such as atmospheric transport and leaching to groundwater (ATSDR, 2002). There is no current potential for industrial releases within Canada.

The primary routes of exposure for the public are through ingestion of food grown in soil contaminated with aldrin or ingestion of animal tissue that has accumulated aldrin. Exposure may also occur through ingestion of drinking water, inhalation, or dermal contact with media containing aldrin, although the potential for these pathways is substantially lower (ATSDR, 2002). Exposure to aldrin and its metabolite dieldrin are often highest in individuals who consume large amounts of fish or fat tissue from marine mammals. Canadians living in Northern communities are often especially susceptible to consuming greater than average amounts of aldrin and dieldrin due to their traditional diets, which include large quantities of fish and marine mammals. Increased inhalation exposure can also result from residual volatilization of aldrin in homes with foundations that were treated for termite control (ATSDR, 2002).

Even though aldrin is no longer in use, it may still be found in food products since it persists in agricultural soil where it was previously used. Exposure in humans is primarily from ingestion of these food products (ATSDR, 2002). Aldrin was last analyzed in the Canadian Total Diet Study in 1985, although it was not detected in any foods (ATSDR, 2002). It has not been analyzed in more recent Total Diet Studies (TDS) (Health Canada, 2009). Dieldrin continues to be detected in a variety of foods, including fruit, vegetables, dairy products and fish, although concentrations have been decreasing since the use of dieldrin was phased out (ATSDR, 2002; Health Canada, 2009). The TDS results from 1978 showed that detectable residue levels of dieldrin in food were generally below 1 µg/kg (McLeod et al., 1980).

Due to the low solubility of both aldrin and dieldrin, the capability of these chemicals to contaminate either surface water or groundwater is considered to be very low. Aldrin and dieldrin concentrations are usually less than 0.01 μg/L in drinking water, and these compounds are rarely present in groundwater (WHO, 2003).

While aldrin is normally rapidly metabolized, dieldrin bioaccumulates and biomagnifies in fish and marine mammal species. Concentrations of dieldrin in seals in northern Canada did not decrease in concentration between 1972 and 1991 (Addison & Smith, 1998).

Aldrin is rapidly metabolized to dieldrin once absorbed in the body. Dieldrin is initially distributed throughout the body, but within a few hours it is redistributed primarily to fat, with smaller amounts being redistributed to the kidneys and lymph nodes (ATSDR, 2002). Dieldrin is estimated to have a biological elimination half-life of approximately 369 days (ATSDR, 2002). Excretion of dieldrin is primarily in feces via bile, but it is also excreted in smaller amounts in urine and in breast milk (ATSDR, 2002). Aldrin and dieldrin can both be measured in blood serum or plasma, as well as in breast milk. Since aldrin is rapidly metabolized into dieldrin upon absorption into the body (Health Canada, 1995), the aldrin concentration is only an indicator of recent exposure, and dieldrin is a more reliable marker of historic or chronic exposure to aldrin. In a pilot study carried out in 1992 in two regions of the Great Lakes area of Ontario, 232 anglers were assessed for the levels of various environmental contaminants in blood and urine samples. While aldrin was not assessed, dieldrin levels were measured; the geometric mean and maximum concentrations of dieldrin in blood plasma were 9.72 µg/kg plasma lipid and 45.7 µg/kg plasma lipid, respectively (Kearney et al., 1995).

Short-term exposure to high concentrations of aldrin has been associated with effects on the central nervous system and the liver (WHO, 2003). Cases of accidental poisonings have resulted in convulsions, seizures, or death (ATSDR, 2002). Long-term exposure to concentrations commonly encountered by the general population through dietary exposure is not thought to pose a health hazard (IPCS, 1999). Chronic exposure to moderate concentrations of aldrin may result in symptoms such as headaches, dizziness, irritability, and vomiting (ATSDR, 2002). Long-term exposure to aldrin and dieldrin has been shown to cause adverse hepatic effects in rats and dogs (ATSDR, 2002).

The United States Environmental Protection Agency classifies aldrin as a probable human carcinogen (Group B2), based on observed liver neoplasms in mice (US EPA, 1993). The International Agency for Research on Cancer has determined aldrin to be Group 3, "not classifiable as to its carcinogenicity to humans" due to inadequate human data and only limited animal data (IARC, 1987). Aldrin and dieldrin are classified as persistent organic pollutants (POP) by the Stockholm Convention, an international agreement to ban or severely restrict the production and use of POPs (UNEP, 2008). 

An acceptable daily intake (ADI) for aldrin and dieldrin combined of 0.1 µg/kg body weight per day has been adopted by Health Canada (2007). This value was based on a No Observed Adverse Effect Level (NOAEL) of 0.025 mg/kg body weight/day in rats for hepatotoxic effects. The Guideline for Canadian Drinking Water Quality for aldrin and dieldrin is 0.007 mg/L (Health Canada, 1995).

Blood plasma levels of aldrin were measured in a subset of the population aged 20-79 years participating in the Canadian Health Measures Survey and are presented as µg/L plasma and µg/kg lipid (Tables 8.2.1a, 8.2.1b). Participants were selected within the specified age range to be a representative sample of the Canadian population. Finding a measurable amount of aldrin in blood plasma is an indicator of recent exposure to aldrin and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for blood plasma levels of aldrin in the Canadian population.

Table 8.2.1a
Aldrin - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/L) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1666 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 526 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 596 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 544 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Males 
Total,
age 20-79
801 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 240 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 281 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 280 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Females
Total,
age 20-79
865 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 286 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 315 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 264 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.2.1b
Aldrin (lipid adjusted *) - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/kg lipid) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1664 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 525 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 596 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 543 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Males 
Total,
age 20-79
801 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 240 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 281 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 280 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Females
Total,
age 20-79
863 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 285 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 315 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 263 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
  • *   Lipids were measured in serum, while the chemical was measured in plasma. See Section 6.0, Statistical Data Analysis for further information.
References

8.2.2 Chlordane (CASRN 57-74-9)

Chlordane (C10H6Cl8) is an organochlorine pesticide that was introduced in the 1940s for agricultural and residential applications in Canada (CCME, 2004). Technical chlordane (CASRN 12789-03-6) is a mixture of over 140 structurally related organochlorine compounds. Some of the major components include:

The most important metabolite of chlordane is oxychlordane (2,3,4,5,6,6a,7,7-octachloro-1a,1b,5,5a,6,6a-hexahydro-2,5-methano-2H-indeno(1,2-b)oxirene) (CASRN 27304-13-8).

Chlordane is a synthetic chemical mixture with no natural sources, and is released to the environment solely by anthropogenic activities. Chlordane was used as a broad-based insecticide for a variety of agricultural crops, for residential applications such as lawns and gardens, as a fumigating agent, and for underground application to homes as termite prevention (ATSDR, 1994; Environment Canada, 2008). Chlordane was never manufactured in Canada and its use was discontinued in 1998. It is no longer registered for use as a pesticide in Canada and cannot be imported to or exported from Canada (Environment Canada, 2005). Production, sale, and use of chlordane in the United States have also been prohibited since 1988 (ATSDR, 1994).

Chlordane has been detected in all environmental media. While its use has been discontinued in Canada, chlordane compounds are very resistant to degradation, and long-range transport of these chemicals is possible (ATSDR, 1994).

The primary source of exposure to the public is through ingestion of foods containing traces of chlordane (ATSDR, 1994), although individuals living in homes previously treated with chlordane may be exposed to elevated indoor air concentrations (ATSDR, 1994). Chlordane can remain for decades in soils where it was previously applied, and food products grown in these soils continue to show detectable concentrations long after use was discontinued in Canada. Occupational exposure may occur with individuals working in agricultural areas where chlordane has previously been applied. Due to the bans on use in Canada and the United States, environmental concentrations are expected to continue to gradually decrease over time, and the potential for new industrial releases is low.

Various foods from the 1993 to 1998 Health Canada Total Diet Studies (TDS), including potato chips, fresh and canned fish, peanut butter, peanuts, candy, microwave popcorn, cucumbers, flour, cookies, and melons, had detectable levels (low parts per billion [ppb]) of chlordane chemicals (Health Canada, 2009a).

Chlordane products generally remain in soil after application. Due to the estimated one-year half-life in soil (UNEP, 2007), strong adsorption onto organic substrates, and very low solubility in water, chlordane residues can persist in soils for over 20 years (ATSDR, 1994). Chlordane may enter water bodies either through leaching from soils and subsequent transport through groundwater, or by deposition from the atmosphere; however, due to their low solubility, once in the water, chlordane tends to bind to sediments (UNEP, 2007). Chlordane compounds are not normally detected in drinking water (WHO, 2004).

Chlordane is absorbed after oral, dermal, and inhalation exposure. Once absorbed, chlordane isomers are preferentially metabolized into oxychlordane, and to a lesser extent, to heptachlor. Biological samples tend to contain primarily oxychlordane and nonachlor compounds (CDC, 2005). Elimination of these chemicals from the body occurs over months to years, and breast milk is a major excretion route in lactating women (CDC, 2005). Samples of maternal blood plasma from the Canadian Arctic in 1994-1999 (Butler Walker et al., 2003) consistently had detectable levels of chlordane products; mean concentrations were 0.05 μg/L for cis-nonachlor (detected in 48.05% of samples), 0.25 μg/L for trans-nonachlor (detected in 98.18% of samples), and 0.23 μg/L for oxychlordane (detected in95.58% of samples). In a pilot study carried out in 1992 in two regions of the Great Lakes area of Ontario, 232 anglers were assessed for the levels of a number of chlordane metabolites in blood plasma. Geometric mean and maximum concentrations (respectively) were 17.1 µg/kg plasma lipid and 48.4 µg/kg plasma lipid for oxychlordane, and 21.0 µg/kg plasma lipid and 116.2 µg/kg plasma lipid for trans-nonachlor (Kearney et al., 1995).

Exposure to high doses of chlordane can result in effects on the nervous system, digestive system, and liver (ATSDR, 1994). The toxicity of chlordane contamination is significantly influenced by environmental and biological degradation processes that have taken place, which are often isomer-specific (ATSDR, 1994).

Chlordane pesticides are not registered for use or sale in Canada by the Pest Management Regulatory Agency (Health Canada, 2009b). Chlordane is classified as a persistent organic pollutant (POP) and as a severe marine pollutant by the Stockholm Convention, an international agreement to ban or severely restrict the production and use of POPs (UNEP, 2008). Health Canada and Environment Canada have conducted a screening assessment that concluded technical grade chlordane is of concern to non-human organisms, but that no further action is required for this substance since no manufacturing or importing of chlordane was reported by Canadian industry (Environment Canada, 2008).

The International Agency for Research on Cancer (IARC) classifies chlordane as a possible human carcinogen (Group 2B) based on inadequate evidence in humans and sufficient evidence in laboratory animals, specifically liver cancer observed in some rodent studies (IARC, 2001). The United States Environmental Protection Agency (US EPA, 1997) has classified chlordane as Group B2, a probable human carcinogen.

A provisional tolerable daily intake (pTDI) for the total sum of chlordane and related chlordane isomer/metabolites of 0.05 µg/kg body weight/day has been adopted by Health Canada (2007). The World Health Organization (WHO, 2004) has established an allowable daily intake (ADI) of 0.0005 mg/kg body weight/day for technical chlordane, based on liver toxicity observed in long-term rat studies.

Blood plasma levels of α-chlordane, γ-chlordane, cis-nonachlor, trans-nonachlor, and oxychlordane were measured in a subset of the Canadian Health Measures Survey (CHMS) population aged 20-79 years and are presented as µg/L plasma and µg/kg lipid (Tables 8.2.2.1a - 8.2.2.5b). Participants were selected within the specified age range to be a representative sample of the Canadian population. Finding a measurable amount of chlordane or its metabolites in blood plasma is an indicator of exposure to chlordane and does not necessarily mean that an adverse health effect will occur. These data provide reference ranges for blood plasma levels of α-chlordane, γ-chlordane, cis-nonachlor, trans-nonachlor, and oxychlordane in the Canadian population.

8.2.2.1 α-Chlordane
Table 8.2.2.1a
α-Chlordane - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/L) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1666 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 526 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 596 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 544 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Males 
Total,
age 20-79
801 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 240 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 281 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 280 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Females
Total,
age 20-79
865 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 286 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 315 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 264 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.2.2.1b
α-Chlordane (lipid adjusted *) - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/kg lipid) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1664 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 525 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 596 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 543 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Males 
Total,
age 20-79
801 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 240 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 281 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 280 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Females
Total,
age 20-79
863 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 285 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 315 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 263 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
  • *   Lipids were measured in serum, while the chemical was measured in plasma. See Section 6.0, Statistical Data Analysis for further information.
8.2.2.2 γ-Chlordane
Table 8.2.2.2a
γ-Chlordane - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/L) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1666 99.70 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 526 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 596 99.50 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 544 99.63 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Males 
Total,
age 20-79
801 99.75 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 240 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 281 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 280 99.29 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Females
Total,
age 20-79
865 99.65 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 286 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 315 99.05 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 264 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.2.2.2b
γ-Chlordane (lipid adjusted *) - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/kg lipid) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1664 99.82 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 525 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 596 99.50 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 543 99.82 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Males 
Total,
age 20-79
801 99.75 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 240 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 281 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 280 99.29 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
Females
Total,
age 20-79
863 99.88 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
20-39 285 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
40-59 315 99.05 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
60-79 263 100.00 -- -- <LOD <LOD <LOD <LOD <LOD <LOD
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
  • *   Lipids were measured in serum, while the chemical was measured in plasma. See Section 6.0, Statistical Data Analysis for further information.
8.2.2.3 cis-Nonachlor
Table 8.2.2.3a
cis-Nonachlor - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/L) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1668 49.04 -- -- <LOD <LOD <LOD 0.01 0.01 0.02
0.01 - 0.01 0.01 - 0.02 0.01 - 0.02
20-39 526 88.40 -- -- <LOD <LOD <LOD <LOD 0.01 0.01
<LOD - 0.01 0.01 - 0.01
40-59 596 49.16 -- -- <LOD <LOD 0.01 0.01 0.01 0.02
<LOD - 0.01 0.01 - 0.01 0.01 - 0.02 0.01 - 0.02
60-79 546 10.99 0.01 0.01 <LOD 0.01 0.01 0.02 0.02 0.03
0.01 - 0.02 0.01 - 0.01 0.01 - 0.01 0.01 - 0.01 0.01 - 0.02 0.02 - 0.03 0.02 - 0.04
Males 
Total,
age 20-79
801 45.32 -- -- <LOD <LOD <LOD 0.01 0.01 0.02
0.01 - 0.01 0.01 - 0.02 0.01 - 0.03
20-39 240 85.00 -- -- <LOD <LOD <LOD <LOD 0.01 0.01
<LOD - 0.01 0.01 - 0.01
40-59 281 45.91 -- -- <LOD <LOD 0.01 0.01 0.01 0.02
<LOD - 0.01 0.01 - 0.01 0.01 - 0.02 0.01 - 0.02
60-79 280 10.71 0.01 0.01 <LOD 0.01 0.01 0.02 0.03 0.04
0.01 - 0.02 0.01 - 0.01 <LOD - 0.01 0.01 - 0.01 0.01 - 0.01 0.01 - 0.02 0.02 - 0.04 0.01 - 0.06
Females
Total,
age 20-79
867 52.48 -- -- <LOD <LOD <LOD 0.01 0.01 0.02
0.01 - 0.01 0.01 - 0.02 0.01 - 0.02
20-39 286 91.26 -- -- <LOD <LOD <LOD <LOD 0.01 0.01
<LOD - 0.01 0.01 - 0.01
40-59 315 52.06 -- -- <LOD <LOD 0.01 0.01 0.01 0.02
<LOD - 0.01 0.01 - 0.01 0.01 - 0.02 0.01 - 0.03
60-79 266 11.28 0.01 0.01 <LOD 0.01 0.01 0.01 0.02 0.02
0.01 - 0.01 0.01 - 0.01 0.01 - 0.01 0.01 - 0.01 0.01 - 0.02 0.02 - 0.03 0.02 - 0.03
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.2.2.3b
cis-Nonachlor (lipid adjusted*) - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/kg lipid) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1666 49.10 -- -- <LOD <LOD <LOD 1.29 2.21 3.13
1.07 - 1.52 1.77 - 2.64 2.20 - 4.06
20-39 525 88.57 -- -- <LOD <LOD <LOD <LOD 1.09 1.74
<LOD - 1.63 0.97 - 2.50
40-59 596 49.16 -- -- <LOD <LOD 0.77 1.23 2.10 3.01
<LOD - 1.03 1.00 - 1.47 1.49 - 2.71 1.50 - 4.52
60-79 545 11.01 2.00 1.52 <LOD 1.07 1.52 2.33 3.55 5.50
1.54 - 2.45 1.27 - 1.82 0.94 - 1.20 1.27 - 1.78 1.85 - 2.81 2.31 - 4.80 2.71 - 8.29
Males 
Total,
age 20-79
801 45.32 -- -- <LOD <LOD <LOD 1.33 2.21 3.00
1.12 - 1.55 1.88 - 2.54 1.86 - 4.14
20-39 240 85.00 -- -- <LOD <LOD <LOD <LOD 1.08 1.51
<LOD - 1.56 0.79 - 2.23
40-59 281 45.91 -- -- <LOD <LOD 0.77 1.24 2.00 2.59
<LOD - 1.11 0.99 - 1.50 1.50 - 2.51 1.38 - 3.80
60-79 280 10.71 2.27 1.70 <LOD 1.15 1.61 2.57 3.89 6.54
1.69 - 2.85 1.39 - 2.09 <LOD - 1.06 0.94 - 1.36 1.28 - 1.95 1.90 - 3.25 1.50 - 6.29 2.81 - 10.26
Females
Total,
age 20-79
865 52.60 -- -- <LOD <LOD <LOD 1.26 2.15 3.14
1.01 - 1.52 1.49 - 2.80 2.15 - 4.13
20-39 285 91.58 -- -- <LOD <LOD <LOD <LOD 1.09 1.79
<LOD - 1.82 0.76 - 2.81
40-59 315 52.06 -- -- <LOD <LOD 0.76 1.17 2.10 3.14
<LOD - 1.01 0.84 - 1.49 1.01 - 3.19 1.35 - 4.93
60-79 265 11.32 1.75 1.37 <LOD 0.99 1.42 2.14 3.04 3.95
1.36 - 2.13 1.14 - 1.64 0.78 - 1.19 1.16 - 1.69 1.68 - 2.60 2.00 - 4.08 2.30 - 5.60
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
  • *   Lipids were measured in serum, while the chemical was measured in plasma. See Section 6.0, Statistical Data Analysis for further information.
8.2.2.4 trans-Nonachlor
Table 8.2.2.4a
trans-Nonachlor - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/L) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1668 6.00 0.05 0.04 0.01 0.02 0.04 0.07 0.11 0.14
0.05 - 0.06 0.03 - 0.04 <LOD - 0.02 0.02 - 0.02 0.03 - 0.04 0.06 - 0.08 0.10 - 0.12 0.12 - 0.16
20-39 526 17.11 0.02 0.02 <LOD 0.01 0.02 0.03 0.04 0.05
0.02 - 0.03 0.01 - 0.02 <LOD - 0.02 0.02 - 0.02 0.02 - 0.03 0.03 - 0.05 0.04 - 0.07
40-59 596 1.68 0.05 0.04 0.02 0.03 0.05 0.07 0.09 0.11
0.05 - 0.06 0.04 - 0.05 0.02 - 0.02 0.03 - 0.04 0.04 - 0.05 0.06 - 0.07 0.08 - 0.11 0.09 - 0.14
60-79 546 0.00 0.10 0.09 0.04 0.06 0.09 0.13 0.16 0.22
0.09 - 0.12 0.08 - 0.10 0.04 - 0.05 0.05 - 0.06 0.07 - 0.10 0.11 - 0.15 0.13 - 0.20 0.14 - 0.30
Males 
Total,
age 20-79
801 4.87 0.05 0.04 0.01 0.02 0.04 0.07 0.11 0.15
0.05 - 0.06 0.03 - 0.04 <LOD - 0.01 0.02 - 0.02 0.03 - 0.04 0.06 - 0.07 0.10 - 0.12 0.13 - 0.17
20-39 240 15.00 0.02 0.02 <LOD 0.01 0.02 0.03 0.04 0.05
0.02 - 0.03 0.01 - 0.02 <LOD - 0.01 0.01 - 0.02 0.02 - 0.03 0.03 - 0.05 0.04 - 0.07
40-59 281 1.07 0.05 0.04 0.02 0.03 0.04 0.07 0.09 0.11
0.05 - 0.06 0.04 - 0.05 0.01 - 0.03 0.03 - 0.04 0.04 - 0.05 0.05 - 0.08 0.07 - 0.11 0.10 - 0.12
60-79 280 0.00 0.11 0.09 0.05 0.06 0.09 0.13 0.18 0.26
0.09 - 0.13 0.08 - 0.10 0.04 - 0.06 0.05 - 0.06 0.07 - 0.10 0.10 - 0.16 0.14 - 0.22 0.14 - 0.38
Females
Total,
age 20-79
867 7.04 0.05 0.04 <LOD 0.02 0.04 0.07 0.11 0.14
0.05 - 0.06 0.03 - 0.04 <LOD - 0.01 0.02 - 0.02 0.03 - 0.04 0.06 - 0.08 0.09 - 0.13 0.12 - 0.16
20-39 286 18.88 0.02 0.02 <LOD 0.01 0.02 0.03 0.04 0.05
0.02 - 0.03 0.01 - 0.02 <LOD - 0.02 0.01 - 0.02 0.02 - 0.03 0.03 - 0.05 0.02 - 0.08
40-59 315 2.22 0.06 0.05 0.02 0.03 0.05 0.07 0.09 0.13
0.05 - 0.07 0.04 - 0.05 0.01 - 0.03 0.03 - 0.04 0.04 - 0.06 0.06 - 0.07 0.07 - 0.12 0.08 - 0.17
60-79 266 0.00 0.10 0.08 0.04 0.06 0.08 0.12 0.15 0.20
0.08 - 0.12 0.07 - 0.10 0.03 - 0.05 0.05 - 0.07 0.07 - 0.10 0.10 - 0.14 0.12 - 0.18 0.12 - 0.27
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.2.2.4b
trans-Nonachlor (lipid adjusted *) - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/kg lipid) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1666 6.00 8.51 5.98 1.92 3.53 6.30 11.03 17.59 22.72
7.44 - 9.57 5.29 - 6.77 <LOD - 2.57 3.03 - 4.03 5.41 - 7.20 9.68 - 12.39 14.49 - 20.68 19.44 - 26.01
20-39 525 17.14 4.01 3.04 <LOD 2.08 3.12 4.61 7.15 10.59
3.34 - 4.69 2.56 - 3.61 <LOD - 2.73 2.73 - 3.50 3.94 - 5.28 5.26 - 9.04 7.12 - 14.06
40-59 596 1.68 8.75 7.31 3.65 5.15 7.45 10.83 14.90 18.93
7.72 - 9.78 6.50 - 8.21 3.22 - 4.09 4.50 - 5.80 6.75 - 8.15 9.27 - 12.40 12.13 - 17.67 14.79 - 23.08
60-79 545 0.00 16.07 13.53 6.82 9.68 13.49 19.48 25.85 33.98
13.45 - 18.69 11.70 - 15.65 5.12 - 8.53 8.53 - 10.83 11.43 - 15.54 16.34 - 22.61 19.06 - 32.64 22.18 - 45.77
Males 
Total,
age 20-79
801 4.87 8.49 5.94 1.92 3.30 6.33 10.94 17.13 22.66
7.50 - 9.48 5.21 - 6.76 <LOD - 2.45 2.80 - 3.81 5.30 - 7.35 9.44 - 12.43 13.79 - 20.47 18.82 - 26.49
20-39 240 15.00 3.81 3.01 <LOD 2.12 3.06 4.52 6.90 10.83
3.13 - 4.48 2.50 - 3.63 <LOD - 2.66 2.65 - 3.47 3.68 - 5.36 4.28 - 9.53 6.89 - 14.77
40-59 281 1.07 8.57 7.22 3.58 5.20 7.44 10.82 13.66 17.62
7.45 - 9.69 6.14 - 8.50 2.43 - 4.72 4.32 - 6.08 6.43 - 8.45 8.82 - 12.82 11.75 - 15.56 12.70 - 22.55
60-79 280 0.00 17.27 14.51 7.97 9.76 14.14 20.77 31.09 40.95
14.64 - 19.91 12.60 - 16.71 6.45 - 9.49 8.83 - 10.69 11.80 - 16.49 17.35 - 24.18 23.56 - 38.63 29.71 - 52.19
Females
Total,
age 20-79
865 7.05 8.52 6.03 <LOD 3.70 6.23 11.05 17.94 22.72
7.30 - 9.75 5.25 - 6.93 <LOD - 3.00 2.99 - 4.41 5.15 - 7.31 9.52 - 12.58 14.47 - 21.40 18.99 - 26.46
20-39 285 18.95 4.23 3.07 <LOD 2.07 3.32 4.83 7.13 9.29
3.17 - 5.30 2.45 - 3.85 <LOD - 3.20 2.65 - 4.00 3.91 - 5.76 4.89 - 9.36 1.96 - 16.62
40-59 315 2.22 8.93 7.39 3.68 5.03 7.43 10.82 15.56 18.96
7.63 - 10.23 6.45 - 8.46 3.24 - 4.12 4.27 - 5.79 6.46 - 8.40 9.01 - 12.63 11.23 - 19.89 12.89 - 25.03
60-79 265 0.00 14.95 12.68 6.50 9.31 13.21 18.36 24.26 29.49
12.16 - 17.75 10.76 - 14.95 4.74 - 8.26 7.67 - 10.95 10.89 - 15.52 14.95 - 21.77 18.89 - 29.63 19.48 - 39.50
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
  • *   Lipids were measured in serum, while the chemical was measured in plasma. See Section 6.0, Statistical Data Analysis for further information.
8.2.2.5 Oxychlordane
Table 8.2.2.5a
Oxychlordane - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/L) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1668 2.58 0.03 0.03 0.01 0.01 0.03 0.04 0.07 0.09
0.03 - 0.04 0.02 - 0.03 0.01 - 0.01 0.01 - 0.02 0.02 - 0.03 0.04 - 0.05 0.06 - 0.08 0.08 - 0.10
20-39 526 7.03 0.02 0.01 0.01 0.01 0.01 0.02 0.03 0.04
0.01 - 0.02 0.01 - 0.01 <LOD - 0.01 0.01 - 0.01 0.01 - 0.01 0.02 - 0.02 0.02 - 0.03 0.03 - 0.04
40-59 596 0.84 0.04 0.03 0.02 0.02 0.03 0.04 0.06 0.07
0.03 - 0.04 0.03 - 0.03 0.01 - 0.02 0.02 - 0.03 0.03 - 0.03 0.04 - 0.05 0.05 - 0.06 0.06 - 0.08
60-79 546 0.18 0.07 0.06 0.03 0.04 0.06 0.08 0.11 0.14
0.06 - 0.07 0.05 - 0.06 0.02 - 0.03 0.04 - 0.04 0.05 - 0.06 0.07 - 0.09 0.09 - 0.12 0.11 - 0.17
Males 
Total,
age 20-79
801 2.00 0.03 0.02 0.01 0.01 0.03 0.04 0.07 0.08
0.03 - 0.04 0.02 - 0.03 0.01 - 0.01 0.01 - 0.02 0.02 - 0.03 0.04 - 0.04 0.06 - 0.08 0.07 - 0.09
20-39 240 6.25 0.02 0.01 0.01 0.01 0.01 0.02 0.03 0.04
0.01 - 0.02 0.01 - 0.01 <LOD - 0.01 0.01 - 0.01 0.01 - 0.02 0.02 - 0.03 0.02 - 0.03 0.03 - 0.04
40-59 281 0.00 0.03 0.03 0.01 0.02 0.03 0.04 0.06 0.07
0.03 - 0.04 0.03 - 0.03 0.01 - 0.02 0.02 - 0.02 0.03 - 0.03 0.03 - 0.04 0.05 - 0.06 0.06 - 0.08
60-79 280 0.36 0.06 0.05 0.03 0.04 0.06 0.08 0.10 0.13
0.06 - 0.07 0.05 - 0.06 0.02 - 0.03 0.03 - 0.04 0.05 - 0.06 0.07 - 0.09 0.09 - 0.12 0.10 - 0.17
Females
Total,
age 20-79
867 3.11 0.04 0.03 0.01 0.02 0.03 0.05 0.07 0.10
0.03 - 0.04 0.02 - 0.03 0.01 - 0.01 0.01 - 0.02 0.03 - 0.03 0.05 - 0.05 0.06 - 0.09 0.08 - 0.11
20-39 286 7.69 0.02 0.01 0.01 0.01 0.01 0.02 0.03 0.03
0.01 - 0.02 0.01 - 0.01 <LOD - 0.01 0.01 - 0.01 0.01 - 0.02 0.02 - 0.02 0.02 - 0.03 0.02 - 0.05
40-59 315 1.59 0.04 0.03 0.02 0.02 0.03 0.05 0.06 0.08
0.03 - 0.04 0.03 - 0.04 0.01 - 0.02 0.02 - 0.03 0.03 - 0.04 0.04 - 0.05 0.05 - 0.07 0.06 - 0.11
60-79 266 0.00 0.07 0.06 0.03 0.04 0.06 0.08 0.11 0.14
0.06 - 0.08 0.05 - 0.07 0.02 - 0.04 0.04 - 0.05 0.05 - 0.07 0.07 - 0.10 0.10 - 0.13 0.08 - 0.19
  • a If >40% of samples were below the LOD, the percentile distribution is reported but means were not calculated.
Table 8.2.2.5b
Oxychlordane (lipid adjusted *) - Arithmetic and geometric means, and selected percentiles of plasma concentrations (μg/kg lipid) for the Canadian population aged 20-79 years, Canadian Health Measures Survey Cycle 1, 2007-2009.
  n %<LODa A.M.
95%CI
G.M.
95%CI
10th
95%CI
25th
95%CI
50th
95%CI
75th
95%CI
90th
95%CI
95th
95%CI
Total,
age 20-79
1666 2.58 5.60 4.21 1.50 2.53 4.28 7.33 11.02 14.07
5.05 - 6.15 3.80 - 4.67 1.37 - 1.63 2.19 - 2.87 3.82 - 4.74 6.51 - 8.16 9.88 - 12.17 12.30 - 15.84
20-39 525 7.05 2.89 2.32 1.09 1.51 2.39 3.55 5.56 7.31
2.58 - 3.20 2.05 - 2.62 <LOD - 1.53 1.36 - 1.65 2.03 - 2.75 3.23 - 3.87 4.36 - 6.77 5.40 - 9.22
40-59 596 0.84 5.74 4.98 2.37 3.57 5.14 7.06 9.53 11.14
5.19 - 6.28 4.52 - 5.50 1.83 - 2.91 3.11 - 4.04 4.29 - 5.99 6.18 - 7.95 8.48 - 10.58 9.50 - 12.77
60-79 545 0.18 10.18 8.80 4.13 6.33 8.74 12.68 16.90 20.70
8.86 - 11.50 7.79 - 9.93 3.59 - 4.67 5.60 - 7.05 7.49 - 10.00 11.04 - 14.33 13.80 - 19.99 15.80 - 25.60
Males 
Total,
age 20-79
801 2.00 5.26 4.02 1.62 2.32 4.13 6.69 10.59 12.77
4.71 - 5.81 3.59 - 4.49 1.37 - 1.86 1.99 - 2.66 3.68 - 4.58 5.96 - 7.42 9.42 - 11.76 10.84 - 14.70
20-39 240 6.25 2.83 2.32 1.14 1.65 2.26 3.47 5.09 6.92
2.44 - 3.22 2.05 - 2.63 <LOD - 1.46 1.37 - 1.94 1.93 - 2.60 2.88 - 4.06 3.64 - 6.54 4.57 - 9.28
40-59 281 0.00 5.29 4.67 2.23 3.25 4.69 6.61 9.16 11.00
4.63 - 5.95 4.09 - 5.34 1.70 - 2.76 2.59 - 3.90 3.72 - 5.66 5.98 - 7.23 7.52 - 10.81 9.89 - 12.11
60-79 280 0.36 9.85 8.41 4.06 5.73 8.58 12.20 16.76 20.31
8.61 - 11.09 7.35 - 9.64 3.48 - 4.63 4.75 - 6.71 6.91 - 10.25 10.12 - 14.29 14.26 - 19.26 16.41 - 24.21
Females
Total,
age 20-79
865 3.12 5.94