Report on Human Biomonitoring of Environmental Chemicals in Pooled Samples

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Date published: 2020-12-14

Results of the Canadian Health Measures Survey Cycles 1 (2007–2009), 3 (2012–2013), 4 (2014–2015) and 5 (2016–2017)

1 Introduction
2 Objectives
3 Pooling design and collection
4 Laboratory analyses
5 Statistical data analyses
6 Considerations for interpreting the pooled serum biomonitoring data
- 6.1 Considerations for data analysis
7 Summaries and results for dioxins and furans
- 7.1 Dioxins and furans
8 Summaries and results for flame retardants
9 Summaries and results for organochlorine pesticides
10 Summaries and results for polychlorinated biphenyls
- 10.1 Polychlorinated biphenyls
Appendix A: Limits of detection
Appendix B: Toxic equivalence values for dioxins and dioxin-like compounds

Acknowledgements

This document was made possible by the efforts of the following staff of the National Biomonitoring Program of Health Canada: Annie St-Amand (Section Head), Kate Werry (Report Lead), Jeff Willey (Report Coordinator), Tyler Pollock (Data Coordinator), Alexandre Crew, Sarah Faure, Subramanian Karthikeyan, Christine MacKinnon-Roy, Julie Yome.

The development and implementation of the biomonitoring component of the Canadian Health Measures Survey was achieved through extensive contributions of programs and staff across Health Canada and Statistics Canada. A special thank you goes out to the participants of the survey, without whom this study would not be possible.

1 Introduction

The Canadian Health Measures Survey (CHMS) is a national, ongoing, direct health measures survey led by Statistics Canada in partnership with Health Canada and the Public Health Agency of Canada. Since its launch in 2007, the survey’s principal objective has been to collect health and wellness data and biological specimens from a nationally representative sample of Canadians. Biological specimens are analyzed for indicators of health status, chronic and infectious diseases, nutritional status and environmental chemicals. This information is important for understanding and detecting emerging trends in risk factors and exposures and advancing health surveillance and research in Canada.

The survey is conducted in two-year cycles, with each cycle comprising data collected from approximately 5,800 Canadians aged 3–79 at 16 collection sites across Canada. The collection sites vary from cycle to cycle and are stratified in five regions of Canada (the Atlantic provinces, Québec, Ontario, the Prairie provinces and British Columbia). The CHMS is designed as a cross-sectional survey that is representative of approximately 96%–97% of the Canadian population (Statistics Canada, 2010; Statistics Canada, 2015; Statistics Canada, 2017; Statistics Canada, 2019). Detailed descriptions of the CHMS rationale, survey design, target population, ethical considerations and sampling strategy have been published elsewhere (Beck et al., 2018; Day et al., 2007; Giroux, 2007; Labrecque and Quigley, 2014; Labrecque and Quigley, 2016; Statistics Canada, 2010; Statistics Canada, 2015; Statistics Canada, 2017; Statistics Canada, 2019; Tremblay et al., 2007).

Biological specimen: a sample of material derived from a survey participant, such as blood, urine, saliva, DNA, hair or nail clippings

Environmental chemical: a chemical substance, either human-made or natural, that is present in the environment and to which humans may be exposed through air, water, food, soil, dust or consumer products

Individual sample: a biological specimen from a single survey participant

Persistent organic pollutants: human-made or natural organic compounds that, once released into the environment, remain intact for long periods, become widely distributed geographically, accumulate in the fatty tissues of humans and wildlife, and have harmful impacts on human health and/or the environment

Pooled sample: a single sample containing a combination of multiple individual samples selected using a set of grouping criteria, such as age or sex (in this report, the term "pooled sample" is also referred to as "pool")

Serum: the fluid component of blood plasma remaining after clot formation

The CHMS biomonitoring component measures environmental chemicals and/or their metabolites in survey participants’ blood, urine and hair. During the first five cycles of the CHMS, data for approximately 200 environmental chemicals were collected in individual samples. These data — along with background information on the selection and prioritization of environmental chemicals — have been published in Health Canada’s reports on human biomonitoring of environmental chemicals (Health Canada, 2010; Health Canada, 2015; Health Canada, 2017; Health Canada, 2019). Select persistent organic pollutants, including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), were measured in individual plasma samples from cycle 1 (2007–2009) (Health Canada, 2010). The concentrations detected in these individual samples were frequently below the limits of detection, thereby limiting the ability to develop national means for several of these compounds. Pooling samples was proposed as a cost-effective approach to address the issue of low detection levels.

This report presents national data on the concentrations of environmental chemicals measured in pooled serum collected from Canadians from 2007–2017. Pooled serum samples were included in the biomonitoring component of cycles 1, 3 (2012–2013), 4 (2014–2015) and 5 (2016–2017) of the CHMS. Measurement in pooled serum samples was carried out for 84 environmental chemicals in cycle 1 and for 54 environmental chemicals in cycles 3, 4 and 5. Pooled serum samples were also included in cycle 6 (2018–2019). Collection for cycle 6 was completed in late 2019 and planning for future cycles is under way.

A full list of the chemicals measured in pooled serum as part of four cycles of the CHMS from 2007–2017 is presented in Table 1.1. Note that pooled serum was not included as part of cycle 2 (2009–2011).

Table 1.1
Chemicals measured in pooled serum in the Canadian Health Measures Survey from 2007–2017
Chemical	Cycle 1 (2007–2009)	Cycle 3 (2012–2013)	Cycle 4 (2014–2015)	Cycle 5 (2016–2017)
Dioxins
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)	Yes	Yes	Yes	Yes
1,2,3,7,8-Pentachlorodibenzo-p-dioxin (PeCDD)	Yes	Yes	Yes	Yes
1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (HxCDD)	Yes	Yes	Yes	Yes
1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (HxCDD)	Yes	Yes	Yes	Yes
1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (HxCDD)	Yes	Yes	Yes	Yes
1,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin (HpCDD)	Yes	Yes	Yes	Yes
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (OCDD)	Yes	Yes	Yes	Yes
Furans
2,3,7,8-Tetrachlorodibenzofuran (TCDF)	Yes	Yes	Yes	Yes
1,2,3,7,8-Pentachlorodibenzofuran (PeCDF)	Yes	Yes	Yes	Yes
2,3,4,7,8-Pentachlorodibenzofuran (PeCDF)	Yes	Yes	Yes	Yes
1,2,3,4,7,8-Hexachlorodibenzofuran (HxCDF)	Yes	Yes	Yes	Yes
1,2,3,6,7,8-Hexachlorodibenzofuran (HxCDF)	Yes	Yes	Yes	Yes
1,2,3,7,8,9-Hexachlorodibenzofuran (HxCDF)	Yes	Yes	Yes	Yes
2,3,4,6,7,8-Hexachlorodibenzofuran (HxCDF)	Yes	Yes	Yes	Yes
1,2,3,4,6,7,8-Heptachlorodibenzofuran (HpCDF)	Yes	Yes	Yes	Yes
1,2,3,4,7,8,9-Heptachlorodibenzofuran (HpCDF)	Yes	Yes	Yes	Yes
1,2,3,4,6,7,8,9-Octachlorodibenzofuran (OCDF)	Yes	Yes	Yes	Yes
Flame retardants
Tetrabromobisphenol A (TBBPA)	No	Yes	Yes	Yes
Flame retardants: Hexabromocyclododecane
alpha-Hexabromocyclododecane (α-HBCD)	Yes	Yes	Yes	Yes
beta-Hexabromocyclododecane (β-HBCD)	Yes	Yes	Yes	Yes
gamma-Hexabromocyclododecane (γ-HBCD)	Yes	Yes	Yes	Yes
Flame retardants: Polybrominated diphenyl ethers
4,4'-Dibromodiphenyl ether (PBDE 15)	Yes	No	No	No
2,2',4-Tribromodiphenyl ether (PBDE 17)	Yes	No	No	No
2,4,4'-Tribromodiphenyl ether (PBDE 28)	Yes	No	No	No
3,4,4'-Tribromodiphenyl ether (PBDE 37)	Yes	No	No	No
2,2',4,4'-Tetrabromodiphenyl ether (PBDE 47)	Yes	Yes	Yes	Yes
2,3',4,4'-Tetrabromodiphenyl ether (PBDE 66)	Yes	No	No	No
2,3',4',6-Tetrabromodiphenyl ether (PBDE 71)	Yes	No	No	No
2,4,4′,6-Tetrabromodiphenyl ether (PBDE 75)	Yes	No	No	No
3,3′,4,4′-Tetrabromodiphenyl ether (PBDE 77)	Yes	No	No	No
2,2’,3,4,4’-Pentabromodiphenyl ether (PBDE 85)	Yes	No	No	No
2,2',4,4',5-Pentabromodiphenyl ether (PBDE 99)	Yes	Yes	Yes	Yes
2,2',4,4',6-Pentabromodiphenyl ether (PBDE 100)	Yes	Yes	Yes	Yes
2,3′,4,4′,6-Pentabromodiphenyl ether (PBDE 119)	Yes	No	No	No
3,3′,4,4′,5-Pentabromodiphenyl ether (PBDE 126)	Yes	No	No	No
2,2′,3,4,4′,5′-Hexabromodiphenyl ether (PBDE 138)	Yes	No	No	No
2,2',4,4',5,5'-Hexabromodiphenyl ether (PBDE 153)	Yes	Yes	Yes	Yes
2,2’,4,4’,5,6’-Hexabromodiphenyl ether (PBDE 154)	Yes	No	No	No
2,3,3',4,5,6-Hexabromodiphenyl ether (PBDE 160)	Yes	No	No	No
2,2′,3,4,4′,5,6-Heptabromodiphenyl ether (PBDE 181)	Yes	No	No	No
2,2’,3,4,4’,5’,6-Heptabromodiphenyl ether (PBDE 183)	Yes	No	No	No
2,3,3',4,4',5,6-Heptabromodiphenyl ether (PBDE 190)	Yes	No	No	No
2,3,3′,4,4′,5,5′,6-Octabromodiphenyl ether (PBDE 205)	Yes	No	No	No
2,2',3,3',4,4',5,5',6,6'-Decabromodiphenyl ether (PBDE 209)	Yes	Yes	Yes	Yes
Organochlorine pesticides
Hexachlorobenzene	Yes	Yes	Yes	Yes
Mirex	Yes	No	No	No
Organochlorine pesticides: Chlordane
trans-Nonachlor	Yes	Yes	Yes	Yes
Oxychlordane	No	Yes	Yes	Yes
Organochlorine pesticides: Dichlorodiphenyltrichloroethane
o,p'-Dichlorodiphenyldichloroethylene (o,p'-DDE)	No	Yes	Yes	Yes
p,p'-Dichlorodiphenyldichloroethylene (p,p'-DDE)	Yes	Yes	Yes	Yes
p,p'-Dichlorodiphenyltrichloroethane (p,p'-DDT)	Yes	No	No	No
Organochlorine pesticides: Endosulfan
α-Endosulfan (Endosulfan I)	No	Yes	Yes	Yes
β-Endosulfan (Endosulfan II)	No	Yes	Yes	Yes
Polychlorinated biphenyls
2,2',5-Trichlorobiphenyl (PCB 18)	Yes	No	No	No
2,4,4'-Trichlorobiphenyl (PCB 28)	Yes	No	No	No
2,2',4,5'-Tetrachlorobiphenyl (PCB 49)	Yes	No	No	No
2,2',5,5'-Tetrachlorobiphenyl (PCB 52)	Yes	No	No	No
2,3',4,4'-Tetrachlorobiphenyl (PCB 66)	Yes	No	No	No
2,4,4',5-Tetrachlorobiphenyl (PCB 74)	Yes	Yes	Yes	Yes
3,3',4,4'-Tetrachlorobiphenyl (PCB 77)	Yes	Yes	Yes	Yes
3,4,4',5-Tetrachlorobiphenyl (PCB 81)	Yes	Yes	Yes	Yes
2,2',4,4',5-Pentachlorobiphenyl (PCB 99)	Yes	Yes	Yes	Yes
2,2',4,5,5'-Pentachlorobiphenyl (PCB 101)	Yes	No	No	No
2,3,3',4,4'-Pentachlorobiphenyl (PCB 105)	Yes	Yes	Yes	Yes
2,3,3’,4’,6-Pentachlorobiphenyl (PCB 110)	Yes	No	No	No
2,3,3',4,4'-Pentachlorobiphenyl (PCB 114)	Yes	Yes	Yes	Yes
2,3',4,4',5-Pentachlorobiphenyl (PCB 118)	Yes	Yes	Yes	Yes
2',3,4,4',5-Pentachlorobiphenyl (PCB 123)	Yes	Yes	Yes	Yes
3,3',4,4',5-Pentachlorobiphenyl (PCB 126)	Yes	Yes	Yes	Yes
2,2',3,3',4,4'-Hexachlorobiphenyl (PCB 128)	Yes	No	No	No
2,2',3,4,4',5'-Hexachlorobiphenyl (PCB 138)	Yes	Yes	Yes	Yes
2,2',3,4,5,5'-Hexachlorobiphenyl (PCB 141)	Yes	No	No	No
2,2',3,4',5,5'-Hexachlorobiphenyl (PCB 146)	No	Yes	Yes	Yes
2,2',4,4',5,5'-Hexachlorobiphenyl (PCB 153)	Yes	Yes	Yes	Yes
2,3,3',4,4',5-Hexachlorobiphenyl (PCB 156)	Yes	Yes	Yes	Yes
2,3,3',4,4',5'-Hexachlorobiphenyl (PCB 157)	Yes	Yes	Yes	Yes
2,3',4,4',5,5'-Hexachlorobiphenyl (PCB 167)	Yes	Yes	Yes	Yes
3,3',4,4',5,5'-Hexachlorobiphenyl (PCB 169)	Yes	Yes	Yes	Yes
2,2',3,3',4,4',5-Heptachlorobiphenyl (PCB 170)	Yes	Yes	Yes	Yes
2,2',3,3',5,5',6-Heptachlorobiphenyl (PCB 178)	Yes	No	No	No
2,2',3,4,4',5,5'-Heptachlorobiphenyl (PCB 180)	Yes	Yes	Yes	Yes
2,2',3,4,4',5',6-Heptachlorobiphenyl (PCB 183)	Yes	No	No	No
2,2',3,4',5,5',6-Heptachlorobiphenyl (PCB 187)	Yes	Yes	Yes	Yes
2,3,3’,4,4’,5,5’-Heptachlorobiphenyl (PCB 189)	Yes	Yes	Yes	Yes
2,2',3,3',4,4',5,5'-Octachlorobiphenyl (PCB 194)	Yes	Yes	Yes	Yes
2,2’,3,3’,4,4’,5,6-Octachlorobiphenyl (PCB 195)	Yes	No	No	No
2,2',3,3',4,5',6,6'-Octachlorobiphenyl (PCB 201)	Yes	No	No	No
2,2',3,4,4',5,5',6-Octachlorobiphenyl (PCB 203)	Yes	No	No	No
2,2',3,3',4,4',5,5',6-Nonachlorobiphenyl (PCB 206)	Yes	No	No	No
2,2',3,3',4,4',5,5',6,6'-Decachlorobiphenyl (PCB 209)	Yes	No	No	No

Sections 2–6 of this report describe the design and implementation of the pooled serum biomonitoring component of the CHMS. These are followed by descriptive summaries for each chemical or chemical group, outlining chemical identities, common uses, occurrences in the environment, potential sources of exposure in the human population, toxicokinetics and health effects, Canadian regulatory status and existing Canadian biomonitoring data. Information on the general CHMS survey and the biomonitoring component (individual samples) has been published previously (Health Canada, 2010; Health Canada, 2013; Health Canada, 2015; Health Canada, 2017; Health Canada, 2019; Statistics Canada, 2020). A complete list of chemicals that have been measured or are planned for measurement in pooled and individual blood and urine samples collected as part of the CHMS is available online (Health Canada, 2020).

Data tables specific to each chemical are provided below the relevant summaries. The tables are broken down by age group and sex, and contain descriptive statistics on the distribution of pooled serum concentrations in the sample population. Data from all cycles are presented together in tables for ease of comparison. Downloadable tables are available in comma-separated values (CSV) format through the Government of Canada's open data portal.

Data from all components of the CHMS are available to scientists through Statistics Canada's Research Data Centres Program, and are a resource for additional scientific analyses. Further information about the CHMS can be obtained by contacting Statistics Canada at infostats@canada.ca.

References

Beck, K., Giroux, S., and Tremblay, M. (2018). Sampling documentation for cycle 5 of the Canadian Health Measures Survey. Statistics Canada (internal document).

Day, B., Langlois, R., Tremblay, M., and Knoppers, B. (2007). Canadian Health Measures Survey: Sampling strategy overview. Health Reports, Special Issue Supplement, 18, 31–35. Statistics Canada, Catalogue no. 82-003-S.

Giroux, S. (2007). Canadian Health Measures Survey: Sampling strategy overview. Health Reports, Special Issue Supplement, 18, 31–35. Statistics Canada, Catalogue no. 82-003-S.

Health Canada (2010). Report on Human Biomonitoring of Environmental Chemicals in Canada: Results of the Canadian Health Measures Survey Cycle 1 (2007–2009). Minister of Health, Ottawa, ON. Retrieved February 4, 2020.

Health Canada (2013). Second Report on Human Biomonitoring of Environmental Chemicals in Canada: Results of the Canadian Health Measures Survey Cycle 2 (2009–2011). Minister of Health, Ottawa, ON. Retrieved February 4, 2020.

Health Canada (2015). Third Report on Human Biomonitoring of Environmental Chemicals in Canada: Results of the Canadian Health Measures Survey Cycle 3 (2012–2013). Minister of Health, Ottawa, ON. Retrieved February 4, 2020.

Health Canada (2017). Fourth Report on Human Biomonitoring of Environmental Chemicals in Canada: Results of the Canadian Health Measures Survey Cycle 4 (2014–2015). Minister of Health, Ottawa, ON. Retrieved February 4, 2020.

Health Canada (2019). Fifth Report on Human Biomonitoring of Environmental Chemicals in Canada: Results of the Canadian Health Measures Survey Cycle 5 (2016–2017). Minister of Health, Ottawa, ON. Retrieved February 4, 2020.

Health Canada (2020). Biomonitoring Content Summary for the Canadian Health Measures Survey: Cycles 1–6 (2007–2019). Minister of Health, Ottawa, ON. Retrieved October 14, 2020.

Labrecque, F., and Quigley, A. (2014). Sampling documentation for cycle 3 of the Canadian Health Measures Survey. Statistics Canada (internal document).

Labrecque F., and Quigley, A. (2016). Sampling documentation for cycle 4 of the Canadian Health Measures Survey. Statistics Canada internal document.

Statistics Canada (2010). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 1. Ottawa, ON. Available upon request (infostats@canada.ca).

Statistics Canada (2015). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 3. Ottawa, ON. Available upon request (infostats@canada.ca).

Statistics Canada (2017). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 4. Ottawa, ON. Available upon request (infostats@statcan.gc.ca).

Statistics Canada (2019). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 5. Ottawa, ON. Available upon request (infostats@canada.ca).

Statistics Canada (2020). Canadian Health Measures Survey (CHMS). Ottawa, ON.

Tremblay, M., Wolfson, M., & Connor Gorber, S. (2007). Canadian Health Measures Survey: Rationale, background and overview. Health Reports, Special Issue Supplement, 18, 7–20. Statistics Canada Catalogue no. 82-003-S.

2 Objectives

The primary purpose of the pooled serum biomonitoring component of the Canadian Health Measures Survey (CHMS) is to provide estimates of environmental chemical concentrations in the Canadian population. These estimates can be used to assess chemical exposures and develop policies to reduce Canadians' exposure to toxic chemicals to protect their health.

The pooled serum biomonitoring component was added to the survey to enable analyses of certain environmental chemicals — namely persistent organohalogens — that are difficult to quantify in individual samples. In individual samples, the small blood volume available and low concentrations generally result in a low frequency of detectable results. In addition, the cost of sensitive analytical methods for measuring these persistent organohalogens can be prohibitive. These limitations are addressed by pooling samples: the pools produce larger sample volumes and reduce the number of samples being analyzed, thereby enabling the use of more sensitive analytical techniques, reducing overall costs and increasing the detection frequency such that national estimates of chemical concentrations can be established.

Specific uses of the CHMS pooled serum biomonitoring data include:

establishing baseline concentrations of chemicals in Canadians
providing information for setting priorities and taking action to reduce Canadians' exposure to environmental chemicals and protect their health
assessing the effectiveness of health and environmental risk management actions intended to reduce exposures and health risks from specific chemicals
contributing to international monitoring programs, such as the Stockholm Convention on Persistent Organic Pollutants

3 Pooling design and collection

The pooled serum biomonitoring component of the Canadian Health Measures Survey (CHMS) was designed to address the need for nationally representative data on current population exposures to persistent organohalogens in Canada. This information is important in understanding exposure to risk factors, detecting emerging trends in risk factors and exposures, and advancing health surveillance and research in Canada.

The strategy for creating pools was developed by Statistics Canada (Verret and Giroux, 2010) and designed to meet three specific criteria:

allow estimates for each age group and sex
yield estimates with as little bias as possible
provide quality indicators or measures of variance

This section provides an overview of the sample size and allocation, blood collection, pool formation and methodology, and variance estimation.

3.1 Sample size and allocation

To meet the objective of producing reliable estimates at the national level by age group and sex, the CHMS requires a sample of at least 500 persons in each of the six age groups (3–5, 6–11, 12–19, 20–39, 40–59 and 60–79 years) and of each sex (except in the 3–5-year group), for a total of 11 groups. Cycle 1 (2007–2009) did not include the 3–5-year age group, and subsequent cycles were not designed to provide estimates for the individual sexes for this age group.

Participants were sampled from 16 collection sites across Canada. Within each cycle, collection sites were allocated to the five Canadian regions in proportion to population size, with two sites allocated to the Atlantic region (except in cycle 1, where only one site was allocated), four to the Québec region, six to the Ontario region, two to the Prairies region and two to British Columbia.

3.2 Blood collection

Biospecimen collection for the CHMS was carried out with consenting survey participants through visits to mobile examination centres (MECs). Detailed descriptions of the MEC operations and logistics for cycles 1, 3 (2012–2013), 4 (2014–2015) and 5 (2016–2017) have been published (Bryan et al., 2007; Statistics Canada, 2010; Statistics Canada, 2015; Statistics Canada, 2017; Statistics Canada, 2019).

Some CHMS participants were randomly selected to fast prior to their MEC appointments. Those selected were required to fast for at least 10 hours. Shorter fasting durations were allowed for others. Pregnant women, people with diabetes, children under six years of age, and other special cases were not asked to fast even if they had initially been flagged for fasting. The target fasted subsample size was 2,500 participants aged 6–79 for each cycle.

All blood specimens collected in the MEC were processed and aliquoted in the MEC. Blood specimens were drawn by a certified phlebotomist; the maximum amount depended upon the age of the participant and consent to storage. The approximate volumes drawn over cycles 1, 3, 4 and 5 ranged from 22.0 mL in 3–5-year-olds to 83.0 mL in 20–79-year-olds (Health Canada, 2010; Health Canada, 2015; Health Canada, 2017; Health Canada, 2019).

For the pooled serum biomonitoring component, blood was collected in Vacutainer Serum Separator Tubes and centrifuged to separate serum. In cycles 3, 4 and 5, a minimum volume of 0.5 mL of serum from each participant was aliquoted, and samples were then frozen for storage in the MEC. To maintain sample integrity, all specimens were stored as soon as processing was complete. A four-hour time limit from the point of collection was set for blood samples to be processed and stored; however, for most samples, this was completed within two hours. Once a week, the specimens were shipped on dry ice to the Food Laboratory Toronto, part of Health Canada’s Regulatory Operations and Enforcement Branch (Ontario, Canada). Samples were stored at -80°C until ready for pooling and analyses.

In cycle 1, the pooled serum biomonitoring component was conducted as a secondary study to the original survey. The serum samples used to create the pools were the volume (approximately 0.4 mL per individual) remaining after nutritional biomarker analyses were complete. These serum samples were shipped on dry ice to the reference laboratory in the Food Research Division of Health Canada’s Health Products and Food Branch (Ontario, Canada) for pooling and analyses. Samples were stored at -80°C until ready for extraction and analyses.

3.3 Pool formation and methodology

To simplify laboratory handling and minimize errors related to pooling, the pools were created using the same quantity of specimen from each participant. This approach limited the total quantity of specimen available for the pools. For cycle 1, it was determined that 0.35 mL of serum was available per participant. For the analyses in that cycle, a minimum volume of 25 mL of serum was required per pool to measure contaminant concentration levels. This meant that the pools required serum from at least 71 individuals. In an effort to account for all forms of non-response, serum from 80 participants was combined. “Non-response” included insufficient volume, sample loss during handling, and individual refusal to participate in future studies or share data with Health Canada.

Given these constraints, 59 pools were formed for cycle 1. The pools were distributed by sex and age groups (6–11, 12–19, 20–39, 40–59 and 60–79 years) and did not consider fasting status. The pools comprised specimens from 57–120 individuals, corresponding to total serum pool volumes of 20–42 mL (mean: 27.2 mL) and a total of 4,583 individual participants. Some pools had a high number of individuals with insufficient serum volume, resulting in less than the targeted minimum of 71 individuals.

A similar pooling protocol was used for cycles 3, 4 and 5, with 0.35 mL serum from each participant used to create pools of at least 80 participants with a minimum total volume of 25 mL. To ensure the minimum target of 71 individuals was met for each pool, participants for whom no blood was collected (or where the remaining volume of serum was less than 0.35 mL) were dropped prior to creating the pools. In all, 65 pools were formed for cycle 3 and 67 for cycles 4 and 5. The pools were distributed by age groups (3–5, 6–11, 12–19, 20–39, 40–59 and 60–79 years) and sex (except for those aged 3–5 years). Each pool comprised 71–133 individuals from the approximately 5,500 participants.

Table 3.3.1 provides the number of participants participating in the study and the number of pools formed for each target group in the survey.

Table 3.3.1
Number of participants and pools formed for each target age and sex group in the Canadian Health Measures Survey cycle 1 (2007–2009), cycle 3 (2012–2013), cycle 4 (2014–2015) and cycle 5 (2016–2017)
Cycle	Participants	Pools	Participants/ pool
Total, 3–79 years
1 (2007–2009)	NA	NA	NA
3 (2012–2013)	5,528	65	75–133
4 (2014–2015)	5,504	67	71–127
5 (2016–2017)	5,409	67	71–123
Total, 6-79 years
1 (2007–2009)	4,583	59	57–120
3 (2012–2013)	5,063	59	75–133
4 (2014–2015)	5,027	61	71–127
5 (2016–2017)	4,930	61	71–123
Females, 6-79 years
1 (2007–2009)	2,407	30	57–108
3 (2012–2013)	2,521	29	75–125
4 (2014–2015)	2,517	31	71–121
5 (2016–2017)	2,456	31	71–119
Males, 6-79 years
1 (2007–2009)	2,176	29	61–120
3 (2012–2013)	2,542	30	75–133
4 (2014–2015)	2,510	30	75–127
5 (2016–2017)	2,474	30	74–123
3-5 years
1 (2007–2009)	NA	NA	NA
3 (2012–2013)	465	6	75–85
4 (2014–2015)	477	6	75–92
5 (2016–2017)	479	6	74–104
6–11 years
1 (2007–2009)	801	10	67–105
3 (2012–2013)	934	11	75–117
4 (2014–2015)	924	12	75–84
5 (2016–2017)	909	12	71–85
12-19 years
1 (2007–2009)	786	10	64–108
3 (2012–2013)	978	12	75–112
4 (2014–2015)	982	12	75–100
5 (2016–2017)	986	12	72–123
20-39 years
1 (2007–2009)	992	13	68–102
3 (2012–2013)	1,038	12	75–125
4 (2014–2015)	1,075	13	71–118
5 (2016–2017)	1,047	13	71–114
40-59 years
1 (2007–2009)	1,079	14	64–90
3 (2012–2013)	1,071	12	75–133
4 (2014–2015)	1,050	12	75–127
5 (2016–2017)	1,001	12	75–116
60-79 years
1 (2007–2009)	925	12	57–120
3 (2012–2013)	1,042	12	75–124
4 (2014–2015)	996	12	75–107
5 (2016–2017)	987	12	75–108
NA: data not available as participants under the age of six were not included in cycle 1

The method for creating the pools was developed by Statistics Canada (Verret and Giroux, 2010) and approved by the Health Canada Research Ethics Board. The method took into account the survey design and aimed to produce mean estimates as close as possible to those obtained for individual data (Verret and Giroux 2010).

The CHMS is a sample survey, meaning that the participants represent many other Canadians not surveyed. To ensure the results would be representative of the entire population, Statistics Canada generated sample weights for each group of pooled samples and incorporated them into all estimates presented in the data tables (e.g., arithmetic means). The pool survey weights were calculated from the survey weights for each participant included in the pool. An adjustment factor was applied to correct for the survey weights of omitted participants. Participants were omitted if they were considered non-responsive, usually due to insufficient volume, sample loss during handling, or refusal to participate in future studies or share data with Health Canada.

3.4 Variance estimation

The theory of dependent random groups was used to calculate an estimate of the variance with a conservative bias (Särndal et al., 1992; Verret and Giroux, 2010). In this method, two replicates (dependent random groups) were created, with each replicate including all age–sex groups and an equal number of collection sites randomly assigned from each of the five CHMS regions (the Atlantic provinces, Québec, Ontario, the Prairie provinces and British Columbia). In cycle 1, only one collection site was sampled in the Atlantic region; as such, it was grouped with the Québec region prior to being assigned to a replicate. In cycles 3, 4 and 5, the Atlantic region included two collection sites; as a result, no grouping of regions was required. Once formed, the replicates were adjusted so that an estimate from each would reflect the Canadian population. The serum pools were then constructed with individuals from the sites assigned to that replicate for each age and sex combination.

A simulation study was carried out to measure the stability of the point estimates (arithmetic mean) and variance estimates (coefficient of variation [CV]) for data obtained from pooled samples (Verret and Giroux, 2010). The pooling strategy was simulated from a subsample of individual measurements from cycle 1. Based upon this study, the CV of the arithmetic mean was stable, which indicates that the point estimates themselves are stable. However, the variance estimates obtained from the dependent random groups were found to be very unstable. As such, the CV should only be considered accurate within an order of magnitude. Other measures of variance estimation, such as confidence intervals — or statistical approaches that rely on variance, such as hypothesis testing — should be avoided. This includes drawing definitive conclusions when comparing results over cycles or with other biomonitoring surveys. Despite the unstable variance estimation resulting from sample pooling, the point estimates provided here are considered accurate and reliable.

3.5 Missing data

Missing data in the CHMS pooled serum biomonitoring data set refers to pools for which the concentration of a chemical is unknown due to sample loss resulting from issues encountered during laboratory analyses. While every effort was made to minimize sample loss, issues during analyses were often the result of human error. Sources of sample loss included issues with sample handling, sample preparation and instrumentation. Differences in laboratory methods resulted in some chemicals being more susceptible to losses. For example, in each cycle of the CHMS, data were missing for up to seven pools in the dioxin, furan and dioxin-like polychlorinated biphenyl analyses while data were missing for at most one pool from the polychlorinated biphenyl analyses.

Concentrations presented in the data tables of this report for chemicals impacted by sample loss were calculated using imputed values for the missing data. Specifically, values for these pools were imputed using the weighted mean of available results for the age/sex group that the missing pool represented. To ensure the accuracy and reliability of the point estimates, imputation by the mean was limited to a weighted maximum of 10% of pools for each target population for which data are presented. Imputation also impacts variance estimation; additional caution should be exercised when interpreting the CV for groups with missing pools and imputed data. Arithmetic means and other descriptive statistics and quality indicators were not calculated for population groups impacted by significant sample loss.

References

Bryan, S., St-Denis, M., Wojtas, D. (2007). Canadian Health Measures Survey: Clinic operations and logistics. Health Reports, Special Issue Supplement, 18, 53–69. Statistics Canada Catalogue no. 82-003-S.

Särndal, C.-E., Swensson, B., Wretman, J. (1992). Model assisted survey sampling. New York: Springer-Verlag, Inc.

Statistics Canada (2010). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 1. Ottawa, ON. Available upon request (infostats@canada.ca).

Statistics Canada (2015). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 3. Ottawa, ON. Available upon request (infostats@canada.ca).

Statistics Canada (2017). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 4. Ottawa, ON. Available upon request (infostats@statcan.gc.ca).

Statistics Canada (2019). Canadian Health Measures Survey (CHMS) Data User Guide: Cycle 5. Ottawa, ON. Available upon request (infostats@canada.ca).

Verret, F., and Giroux, S. (2010). La formation de pools de sérums de sang pour l’analyse dans l’Enquête canadienne sur les mesures de la santé. Assemblée annuelle de la SSC.

4 Laboratory analyses

Laboratory analyses of environmental chemicals were performed at Health Canada analytical laboratories. The laboratories developed standardized operating procedures for the analytical methods used to measure environmental chemicals or their metabolites in serum pools. Analytical accuracy and measurement precision were evaluated through rigorous method validation programs at each laboratory.

To ensure ongoing accuracy and precision of results, several quality control measures were employed as part of the Canadian Health Measures Survey (CHMS). The methods and quality control protocols used in the analyses of the environmental chemicals are described below.

4.1 Dioxins, furans and dioxin-like polychlorinated biphenyls

Polychlorinated dibenzo-p-dioxin (dioxin), polychlorinated dibenzofuran (furan) and dioxin-like polychlorinated biphenyl (PCB) analyses in serum pools from cycle 1 (2007–2009) were performed by the Food Research Division of Health Canada’s Health Products and Food Branch (Ontario, Canada). The analytical methods and quality control procedures for cycle 1 are described in detail elsewhere (Rawn et al., 2012). Dioxin, furan and dioxin-like PCB analyses in serum pools from cycles 3 (2012–2013), 4 (2014–2015) and 5 (2016–2017) were performed at the Food Laboratory Toronto, part of Health Canada’s Regulatory Operations and Enforcement Branch (Ontario, Canada) (Health Canada, 2019a).

These analyses measured seven dioxin congeners, 10 furan congeners and four coplanar dioxin-like PCBs in all four cycles. Pooled serum samples were aliquoted and spiked with isotopically labelled standards of dioxins, furans and dioxin-like PCBs. Samples were then homogenized in a mixture of ethanol, saturated aqueous ammonium sulfate and hexane. Solvent was extracted and digested in concentrated sulphuric acid to remove lipids. Samples were then subjected to secondary clean-up and fractionation via tandem cesium silicate and Florisil columns followed by carbon columns. Recovery standards were added to the final sample extract. Qualitative and quantitative analyses were performed using high-resolution >gas chromatography/high-resolution selected ion mass spectrometry (GC/HRMS). Quality control was ensured by evaluating a reagent blank and a National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) with every sample batch. The laboratory also participated in the Interlaboratory Comparison Program for Dioxins and Furans in Serum offered by the Centre de toxicologie du Québec (CTQ), Institut National de Santé Publique du Québec (INSPQ) (INSPQ, 2020b). The results of the quality control measures from reference materials and external assessment programs were consistently within the acceptable ranges set by the proficiency testing providers.

4.2 Flame retardants

4.2.1 Hexabromocyclododecane and tetrabromobisphenol A

Hexabromocyclododecane (HBCD) analyses in serum pools from cycle 1 were performed by the Food Research Division of Health Canada’s Health Products and Food Branch (Ontario, Canada). Analytical methods and quality control procedures for cycle 1 are described in detail elsewhere (Rawn et al., 2014). HBCD and tetrabromobisphenol A (TBBPA) analyses in serum pools from cycles 3, 4 and 5 were performed at the Food Laboratory Toronto, part of Health Canada’s Regulatory Operations and Enforcement Branch (Ontario, Canada) (Health Canada, 2018a). These analyses measured three HBCD isomers (α-HBCD, β-HBCD and γ-HBCD) in all four cycles and TBBPA in cycles 3, 4 and 5. Pooled serum samples were aliquoted and spiked with isotopically labelled standards of each analyte. Samples were extracted using a hexane and tert-butyl methyl ether solution. The resulting extract was passed through an acidified silica gel column to collect a first fraction containing HBCD eluted with hexane and a second fraction containing TBBPA eluted with dichloromethane. The two fractions were then subjected to secondary clean-up with sulphuric acid and reconstituted in a methanol and water solution. Qualitative and quantitative analyses were performed using liquid chromatography tandem mass spectrometry (LC/MS/MS) with multiple reaction monitoring (MRM). Quality control was ensured by evaluating in-house pooled serum spiked with HBCD and TBBPA standards with every sample batch. Results of in-house quality control measures were consistently within the acceptable ranges set by the laboratory (± 30%).

4.2.2 Polybrominated diphenyl ethers

Polybrominated diphenyl ether (PBDE) analyses in serum pools from cycle 1 were performed by the Food Research Division of Health Canada’s Health Products and Food Branch (Ontario, Canada). Analytical methods and quality control procedures for cycle 1 are described in detail elsewhere (Rawn et al., 2014). PBDE analyses in serum pools from cycles 3, 4 and 5 were performed at the Food Laboratory Toronto, part of Health Canada’s Regulatory Operations and Enforcement Branch (Ontario, Canada) (Health Canada, 2019b). These analyses measured 23 PBDEs in cycle 1 and five PBDEs in cycles 3, 4 and 5. Pooled serum samples were aliquoted and spiked with isotopically labelled standards of PBDEs. Samples were then homogenized in a mixture of ethanol, saturated aqueous ammonium sulfate and hexane. Solvent was extracted and digested in concentrated sulphuric acid to remove lipids. Samples were then subjected to secondary clean-up and fractionation via tandem cesium silicate and Florisil columns followed by a carbon column. Recovery standards were added to the final sample extract. Qualitative and quantitative analyses were performed using high-resolution GC/HRMS. Quality control was ensured by evaluating a reagent blank and a NIST SRM with every sample batch. The laboratory also participated in the Arctic Monitoring and Assessment Programme (AMAP) Ring Test for Persistent Organic Pollutants in Human Serum offered by the CTQ, INSPQ, Québec, Canada (INSPQ, 2020a). The results of quality control measures from reference materials and external assessment programs were consistently within the acceptable ranges set by the proficiency testing providers.

4.3 Organochlorine pesticides

Organochlorine pesticide and metabolite analyses in serum pools from cycle 1 were performed by the Food Research Division of Health Canada’s Health Products and Food Branch (Ontario, Canada). Analytical methods and quality control procedures for cycle 1 were the same as those conducted for the measurement of PCBs and are described in detail elsewhere (Rawn et al., 2012). Organochlorine analyses in serum pools from cycles 3, 4 and 5 were performed at the Food Laboratory Toronto, part of Health Canada’s Regulatory Operations and Enforcement Branch (Ontario, Canada) (Health Canada, 2018b). These analyses measured hexachlorobenzene, trans-nonachlor (a chlordane component), oxychlordane (a chlordane metabolite), and p,p'-dichlorodiphenyldichloroethylene (a dichlorodiphenyltrichloroethane metabolite) in all four cycles. Also measured were mirex and p,p'-dichlorodiphenyldichloroethane in cycle 1, as well as endosulfan (endosulfan I and II) and another dichlorodiphenyltrichloroethane metabolite (o,p'-dichlorodiphenyldichloroethylene) in cycles 3, 4 and 5. Pooled serum samples were aliquoted and spiked with isotopically labelled standards of each analyte. Samples were then extracted using a mixture of ethanol, saturated aqueous ammonium sulfate, and hexane. The organic fraction was isolated using liquid–liquid extraction. Samples were then subjected to secondary clean-up via gel permeation chromatography using a porous cross-linked polystyrene polymer gel and cyclohexane-dichloromethane. Samples were transferred to autosampler vials and reconstituted in nonane. Qualitative and quantitative analyses were performed using gas chromatography triple quadrupole mass spectrometry (GC/MS/MS) with MRM. Quality control was ensured by evaluating a reagent blank and a NIST SRM with every sample batch. The laboratory also participated in the AMAP Ring Test for Persistent Organic Pollutants in Human Serum offered by the CTQ, INSPQ, Québec, Canada (INSPQ, 2020a). Results of quality control measures from reference materials and external assessment programs were consistently within the acceptable ranges set by the proficiency testing providers.

4.4 Polychlorinated biphenyls

Polychlorinated biphenyl (PCB) analyses in serum pools from cycle 1 were performed by the Food Research Division at Health Canada’s Health Products and Food Branch (Ontario, Canada). Analytical methods and quality control procedures for cycle 1 are described in detail elsewhere (Rawn et al., 2012). PCB analyses in serum pools from cycles 3, 4 and 5 were performed at the Food Laboratory Toronto, part of Health Canada’s Regulatory Operations and Enforcement Branch (Ontario, Canada) (Health Canada, 2019c). These analyses measured 32 PCBs in cycle 1 and 17 PCBs in cycles 3, 4 and 5. Pooled serum samples were aliquoted and spiked with isotopically labelled standards of PCBs. Samples were then homogenized in a mixture of ethanol, saturated aqueous ammonium sulfate and hexane. Solvent was extracted and digested in concentrated sulphuric acid to remove lipids. Samples were then subjected to secondary clean-up and fractionation via tandem cesium silicate and Florisil columns. Recovery standards were added to the final sample extract. Qualitative and quantitative analyses were performed using high-resolution GC/HRMS. Quality control was ensured by evaluating a reagent blank and a NIST SRM with every sample batch. The laboratory also participated in the AMAP Ring Test for Persistent Organic Pollutants in Human Serum offered by the CTQ, INSPQ, Québec, Canada (INSPQ, 2020a). Results of quality control measures from reference materials and external assessment programs were consistently within the acceptable ranges set by the proficiency testing providers.

4.5 Lipids

Lipid content determination of serum pools from cycle 1 was performed by the Food Research Division of Health Canada’s Health Products and Food Branch (Ontario, Canada). Lipid content determination of serum pools from cycles 3, 4 and 5 was performed at the Food Laboratory Toronto, part of Health Canada’s Regulatory Operations and Enforcement Branch (Ontario, Canada). This analysis measured the weight of lipid relative to the weight of serum. Lipid content was determined gravimetrically in cycles 1, 3 and 5. The crude sample was extracted in hexane and dried under a gentle stream of high-purity nitrogen to achieve a constant weight. Following lipid determination, samples were re-dissolved in hexane before proceeding with the chemical analyses. In cycle 4, lipid content was determined following a modified version of the AOAC official method 996.06 (AOAC, 2001). Serum pools were aliquoted and lipids were hydrolyzed with a mixture of hydrochloric acid and ethanol, then extracted with a mixture of hexane and ethyl ether. The extracted fatty acids were methylated in a transesterification process using boron trifluoride in methanol. Finally, quantification was performed using gas chromatography with flame ionization detection before an empirical correction (based on the analysis of AMAP proficiency test samples) was applied to account for lipids not captured by the above transesterification process. Measures of lipid content were comparable across all four cycles.

References

AOAC International (2001). Fat (total, saturated and unsaturated) in foods, hydrolytic extraction gas chromatographic method, 18th Edition, AOAC Official Method 996.06.

Health Canada (2018a). Analytical method report for the determination of α, β, γ–Hexabromocyclododecane and tetrabromobisphenol A in human serum. Food Laboratory Toronto, Regulatory Operations and Enforcement Branch, Health Canada, Toronto, ON.

Health Canada (2018b). Analytical method report for the determination of organochlorine pesticides and metabolites in human serum. Food Laboratory Toronto, Regulatory Operations and Enforcement Branch, Health Canada, Toronto, ON.

Health Canada (2019a). Method of analysis for polychlorinated dibenzo-para-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (coplanar-PCBs). Food Laboratory Toronto, Regulatory Operations and Enforcement Branch, Health Canada, Toronto, ON.

Health Canada (2019b). Method of analysis for polybrominated diphenyl ethers (PBDEs). Food Laboratory Toronto, Regulatory Operations and Enforcement Branch, Health Canada, Toronto, ON.

Health Canada (2019c). Method of analysis for polychlorinated biphenyls (PCBs). Food Laboratory Toronto, Regulatory Operations and Enforcement Branch, Health Canada, Toronto, ON.

INSPQ (Institut national de santé publique Québec) (2020a). AMAP Ring Test for Persistent Organic Pollutants in Human Serum. Retrieved March 19, 2020.

INSPQ (Institut national de santé publique Québec) (2020b). Interlaboratory Comparison Program for Dioxin Furans in Serum. Retrieved March 19, 2020.

Rawn, D.F., Ryan, J.J., Sadler, A.R., Sun, W.F., Haines, D., Macey, K., Van Oostdam, J. (2012). PCDD/F and PCB concentrations in sera from the Canadian Health Measures Survey (CHMS) from 2007 to 2009. Environment International, 47, 48–55.

Rawn, D.K.F., Ryan, J.J., Sadler, A.R., Sun, W.-F., Weber, D., Laffey, P., Haines, D., Macey, K., van Oostdam, J. (2014). Brominated flame retardant concentrations in sera from the Canadian Health Measures Survey (CHMS) from 2007 to 2009. Environment International, 63, 26–34.

5 Statistical data analyses

Descriptive statistics and quality indicators for the concentrations of environmental chemicals in pooled samples were generated using the Statistical Analysis System software (SAS Institute Inc., version 9.4, 2013).

Data tables are presented for each chemical measured in pooled samples from cycle 1 (2007–2009), 3 (2012–2013), 4 (2014–2015) and/or 5 (2016–2017). The tables include the total number of pools, the minimum concentrations, the maximum concentrations, the weighted arithmetic means and the coefficients of variation (CVs) associated with the arithmetic means. For each chemical, results are presented for the total population aged 6–79 in cycle 1; aged 3–79 in cycles 3, 4 and 5; and in some cases, both, for comparison purposes. Results are also presented by age group and sex. LODs for each chemical and survey cycle are provided alongside the respective data table and collectively in Appendix A. LODs are provided in lipid-adjusted units. Some chemicals measured in pooled serum have constant LODs across all samples analyzed. This includes organochlorine pesticides and metabolites, hexabromocyclododecane and tetrabromobisphenol A in cycles 3, 4 and 5. For these chemicals, the LOD value is provided alongside the respective data tables and in Appendix A. Other chemicals have an individual LOD for each pool, as the LOD can vary based on the amount of pooled serum analyzed and with daily fluctuations in instrument performance. This includes all chemicals in cycle 1 and polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, polychlorinated biphenyls and polybrominated diphenyl ethers in cycles 3, 4 and 5. For these chemicals, the mean LOD values for cycles 1, 3, 4 and 5 are provided alongside the respective data tables and in Appendix A. The LOD range (minimum to maximum) is also provided in Appendix A for cycles 3, 4 and 5.

Measurements that fell below the LOD for the laboratory analytical method were assigned a value equal to half the constant LOD or the individual LOD, depending on the type of LOD reported. Pools with missing data due to sample loss were assigned a value equal to the weighted mean of available results for the age/sex group that the missing pool represented. If the proportion of results below the LOD was greater than 40% or the weighted proportion of results with data missing was greater than 10%, arithmetic means were not calculated. When the result for at least one pool was below the LOD, the minimum concentration was reported as <LOD. When the results for all pools were below the LOD, the maximum concentration was also reported as <LOD. For most chemicals, the maximum concentration presented is a measured value. However, there are some instances where the maximum LOD was over twice the highest measured concentration and, as a result, the maximum concentration presented is an imputed LOD.

The environmental chemicals measured in serum pools are lipophilic and concentrate in the body’s lipid stores, including in serum. Lipid content of the serum pools was measured at the time of sample analysis. Data for these chemicals were adjusted for lipid content and are presented as the weight of chemical per gram of lipid. Separate tables present unadjusted data as the weight of chemical per whole weight of serum to allow for comparison with studies using these units.

Under the Statistics Act, Statistics Canada is required to ensure participant confidentiality. Most estimates presented in the data tables are based on a small number of pooled samples. However, since many individual participants are represented in these pooled samples, it is not possible to extract information about any one individual. Therefore, point estimates based on a small number of pooled samples are not suppressed.

6 Considerations for interpreting the pooled serum biomonitoring data

The pooled serum biomonitoring component of the Canadian Health Measures Survey (CHMS) was designed to provide estimates of environmental chemical concentrations in the Canadian population. The survey is nationally representative. The first cycle covers approximately 96% of the Canadian population aged 6–79, while subsequent cycles cover approximately 96%–97% of the Canadian population aged 3–79. The pools were created across collection sites; as such, the pooling strategy does not permit breakdown of data by region, province or collection site. In addition, the CHMS design did not target specific exposure scenarios; consequently, it did not select or exclude participants on the basis of their potential for low or high exposures to environmental chemicals.

Biomonitoring in pooled samples provides an estimate of how much of a chemical is present in a population. The absence of a chemical does not necessarily mean a population has not been exposed. While the ability to measure environmental chemicals at very low concentrations has advanced in recent years, the technology may not be capable of detecting current exposures for certain chemicals.

While most persistent organohalogens are measured as the parent compound or specific congener, some organochlorines are measured as metabolites. Parent compounds may be broken down or metabolized in the body into one or more metabolites. For example, the organochlorine pesticide dichlorodiphenyltrichloroethane is broken down into several metabolites, including dichlorodiphenyldichloroethylene and dichlorodiphenyldichloroethane.

Biomonitoring cannot tell us the source or route of exposure. The amount of chemical measured indicates the total amount that has entered the population via all routes (ingestion, inhalation and skin contact) and from all sources (air, water, soil, food and consumer products). The detection of the chemical may be the result of exposure to a single source or multiple sources. In addition, in most cases, biomonitoring cannot distinguish between natural and anthropogenic sources. Some chemicals, such as polychlorinated dibenzo-p-dioxins (dioxins) and polychlorinated dibenzofurans (furans), occur naturally in the environment and are also present in human-made products. While it is not possible to attribute exposures to specific sources or routes, CHMS data from individual samples have been used to support research on the predictors of exposure to certain chemicals, including polychlorinated biphenyls (PCBs) (Singh et al., 2019). However, the pooling of samples limits the ability to examine these links, as the pooling design did not consider predictors of exposure.

The presence alone of a chemical in a population does not necessarily mean it will cause a health effect. Factors such as the dose, the toxicity of the chemical and the duration and timing of exposure are important to determine whether potential adverse health effects may occur. CHMS data from individual samples have been used as evidence to support research on the potential links between exposure to certain chemicals and specific health effects. However, the pooling of samples limits the ability to examine these links, as health end points were not considered in the pooling design.

For some chemicals, such as PCBs, research studies have provided a general understanding of the population-level health risks associated with different concentrations in blood (ANSES, 2010). From a screening perspective, biomonitoring equivalents (BEs) have been developed based upon existing exposure guidance values, and are a tool to help interpret biomonitoring data in a health-risk context at the population level (Hays et al., 2008). BEs have been used to screen existing biomonitoring data from the CHMS (Faure et al., 2020; St-Amand et al., 2014). However, for many chemicals, further research is needed to understand the potential health effects, if any, associated with different blood concentrations. Further, certain populations — such as children, pregnant women, the elderly or those who are immunocompromised — may be more susceptible to the effects of exposure.

6.1 Considerations for data analysis

Pooled serum data from cycle 1 (2007–2009) for polychlorinated biphenyls (PCBs), dioxins, furans, polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) were published previously (Rawn et al., 2012; Rawn et al., 2014). The statistical approach used by Statistics Canada in the development of the data included in these previous publications differs from that used in the current report. In addition, there was a problem identified with the original imputation of measurements that fell below the limits of detection (LODs) used by Rawn et al., that has been rectified for this report. As a result, the previously published data are not directly comparable with the data presented in this report.

6.1.1 Instability of variance estimates

Estimates such as the arithmetic mean from a sample survey inevitably include sampling errors. Measurements of the possible scope of sampling errors are based on the standard error of the estimates drawn from the survey results. To get a better indication of the size of the standard error, it is often more useful to express the standard error in terms of the estimate being measured. The resulting measure, the coefficient of variation (CV), is obtained by dividing the standard deviation of the estimate by the estimate itself, and is expressed as a percentage of the estimate. For the pooled serum biomonitoring component of the CHMS, variance estimates including CVs are unstable due to the small number of pools (57–69) and collection sites (15–16) for each cycle. Without stable CVs, it is not recommended to generate confidence interval estimates or to conduct hypothesis testing.

The instability of the CVs limits the extent of analyses that can be done with pooled serum data from the CHMS. The CHMS pooled serum biomonitoring data set includes arithmetic means and accompanying CVs for the total population and subpopulations (sex and age group) for the substances measured in cycle 1 (2007–2009), cycle 3 (2012–2013), cycle 4 (2014–2015) and cycle 5 (2016–2017). It is important to note that although arithmetic means may be compared across cycles or among subpopulations, it is not possible to definitively conclude whether they are statistically or meaningfully different from each other without the option of generating confidence intervals or conducting hypothesis testing. Therefore, caution must be exercised when interpreting the data. This is especially the case for comparisons of arithmetic means with high CVs.

The following guidelines, adapted from those used by Statistics Canada, are provided for interpreting arithmetic means based on their CVs:

When a CV is below 16.6%, an arithmetic mean may be considered reliable.
When a CV is between 16.6% and 33.3%, an arithmetic mean may be considered less reliable due to the high sampling variability associated with the estimate; data should be used with caution.
When a CV is greater than 33.3%, an arithmetic mean may be considered the least reliable due to the very high sampling variability associated with the estimate; data should be used with a high degree of caution.

Some arithmetic means were calculated using imputed data to account for missing pools. Additional caution should be exercised when interpreting the CV for these arithmetic means as imputation can impact variance estimation.

6.1.2 Variation between cycles

For those chemicals measured in multiple cycles, it is important to note that changes in analytical methods across cycles may contribute to variations in results. The LODs for certain analytical methods have changed from cycle to cycle as a result of improvements to analytical methods (Appendix A). As a result, there may be some instances where results were reported as <LOD in a past cycle and as a concentration >LOD in a more recent cycle. This difference in LODs should be considered when interpreting data from multiple cycles.

6.1.3 Comparability with individual data

Pooled sample data are equivalent to the arithmetic mean of the results from each individual sample in the pool. In individual samples, estimates of central tendency are best made using a geometric mean due to the log-normal distribution of the data. In other words, the geometric mean is preferable for individual sample data because it is less influenced by a small number of high values that are common when measuring chemicals in biological samples. For these types of data with log-normal distribution, arithmetic means are expected to be higher than geometric means. Therefore, the arithmetic means presented for the pooled sample data are expected to be higher than the geometric means of individual sample data reported elsewhere, including in Health Canada’s reports on human biomonitoring of environmental chemicals. The difference between arithmetic and geometric means should be considered when comparing results from pooled sample data with those of individual sample data.

6.1.4 Lipid adjustment

The environmental chemicals measured in pooled serum — namely, persistent organohalogens — are lipophilic, and concentrate in lipid stores within the body. As such, data were adjusted for serum lipid content and are presented on a lipid weight basis, as is commonly and routinely done for these chemicals (HHEAR, 2020). Data are also presented on a serum weight basis for comparison with studies in which lipids were not measured. It is worth noting that serum lipid levels can be affected by variables such as sex, age, fasting status and body mass index (BMI), which may result in differences among demographic and sampling groups within a single cycle (Costanza et al., 2005). In addition, a subset (approximately half) of the CHMS participants aged 6–79 fasted for a minimum of 10 hours prior to blood sampling. For data presented on a serum weight basis, concentrations of lipophilic chemicals are generally higher in non-fasting samples than in fasting samples (Phillips et al., 1989). However, correcting for total serum lipids results in similar chemical concentrations in fasting and non-fasting samples (Phillips et al., 1989).

References

ANSES (Agence nationale de sécurité sanitaire de l’alimentation, de l’environnement et du travail). 2010. Opinion of the French Food Safety Agency on interpreting the health impact of PCB concentration levels in the French population. ANSES, Paris. Retrieved March 3, 2020.

Costanza, M.C., Cayanis, E., Ross, B.M., Flaherty, M.S., Alvin, G.B., Das, K., Morabia, A. (2005). Relative contributions of genes, environment, and interactions to blood lipid concentrations in a general adult population. American Journal of Epidemiology, 161 (8), 714–724.

Faure, S., Noisel, N., Werry, K., Karthikeyan, S., Aylward, L.L, St-Amand, A. (2020). Evaluation of human biomonitoring data in a health risk based context: An updated analysis of population level data from the Canadian Health Measures Survey. International Journal of Hygiene and Environmental Health, 223 (1), 267–280.

Hays, S.M., Aylward, L.L., LaKind, J.S., Bartels, M.J., Barton, H.A., Boogaard, P.J., Brunk, C., DiZio, S., Dourson, M., Goldstein, D.A., et al. (2008). Guidelines for the derivation of biomonitoring equivalents: report from the biomonitoring equivalents expert workshop. Regulatory Toxicology and Pharmacology, 51 (3), S4–S15.

HHEAR (Human Health Exposure Analysis Resource) (2020). Lipid Adjustment of Persistent Organic Pollutants. Retrieved March 20, 2020.

Phillips, D.L., Pirkle, J.L., Burse, V.W., Bernert Jr., J.T., Henderson, L.O., Needham, L.L. (1989). Chlorinated hydrocarbon levels in human serum: Effects of fasting and feeding. Archives of Environmental Contamination and Toxicology, 18 (4), 495–500.

Singh, K., Karthikeyan, S., Vladisavljevic, D., St-Amand, A., Chan, H.M. (2019). Factors associated with plasma concentrations of polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (p,p’-DDE) in the Canadian population. International Journal of Environmental Health Research, 29(3), 326–347.

St-Amand, A., Werry, K., Aylward, L.L., Hays, S.M., Nong, A. (2014). Screening of population level biomonitoring data from the Canadian Health Measures Survey in a risk-based context. Toxicology Letters, 231 (2), 126–134.

7 Summaries and results for dioxins and furans

7.1 Dioxins and furans

Dioxins and furans are classes of toxicologically and structurally similar chlorinated organic chemicals. This group comprises 75 polychlorinated dibenzo-p-dioxins (dioxins) and 135 polychlorinated dibenzofurans (furans) (ATSDR, 1994; ATSDR, 1998). Of the 210 congeners, 17 are considered of greatest concern to human health. These congeners were measured as part of the Canadian Health Measures Survey (CHMS) and are listed in Table 7.1.1 and Table 7.1.2.

Table 7.1.1
Polychlorinated dibenzo-p-dioxins measured in pooled serum in the Canadian Health Measures Survey cycle 1 (2007–2009), cycle 3 (2012–2013), cycle 4 (2014–2015) and cycle 5 (2016–2017)
Compound name	CASRN
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)	1746-01-6
1,2,3,7,8-Pentachlorodibenzo-p-dioxin (PeCDD)	40321-76-4
1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (HxCDD)	39227-28-6
1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (HxCDD)	57653-85-7
1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (HxCDD)	19408-74-3
1,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin (HpCDD)	35822-46-9
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (OCDD)	3268-87-9

Table 7.1.2
Polychlorinated dibenzofurans measured in pooled serum in the Canadian Health Measures Survey cycle 1 (2007–2009), cycle 3 (2012–2013), cycle 4 (2014–2015) and cycle 5 (2016–2017)
Compound name	CASRN
2,3,7,8-Tetrachlorodibenzofuran (TCDF)	51207-31-9
1,2,3,7,8-Pentachlorodibenzofuran (PeCDF)	57117-41-6
2,3,4,7,8-Pentachlorodibenzofuran (PeCDF)	57117-31-4
1,2,3,4,7,8-Hexachlorodibenzofuran (HxCDF)	70648-26-9
1,2,3,6,7,8-Hexachlorodibenzofuran (HxCDF)	57117-44-9
1,2,3,7,8,9-Hexachlorodibenzofuran (HxCDF)	72918-21-9
2,3,4,6,7,8-Hexachlorodibenzofuran (HxCDF)	60851-34-5
1,2,3,4,6,7,8-Heptachlorodibenzofuran (HpCDF)	67562-39-4
1,2,3,4,7,8,9-Heptachlorodibenzofuran (HpCDF)	55673-89-7
1,2,3,4,6,7,8,9-Octachlorodibenzofuran (OCDF)	39001-02-0

Dioxins and furans are produced from natural processes — such as forest fires and volcanic eruptions — and as a result of anthropogenic activities (Health Canada, 2006). Incineration processes are a major anthropogenic source, and include accidental burning of transformers and electrical equipment as well as intentional burning of materials such as household trash, municipal and medical waste, treated woods and fossil fuels. Other sources of anthropogenic releases are metal processing, chlorine bleaching of pulp and paper, electrical power generation, tobacco smoke and manufacturing of chemicals, such as pesticides (Health Canada, 2006). Dioxins and furans are not used commercially or produced intentionally by industry (except for scientific research purposes); rather, they are generated as impurities during the manufacture of other chemicals or products (ATSDR, 1994).

Dioxins and furans enter the environment mainly through air and are found in the environment throughout the world (WHO, 2010). Once in the atmosphere, they can undergo long-range transport (Health Canada, 2006). The highest levels of these chemicals are found in soils, sediments and foods (WHO, 2010). In the environment, dioxins and furans are bioaccumulative and persistent. These properties are more pronounced in higher chlorinated congeners and congeners with specific positions of chlorination (WHO, 2010). TCDD has an estimated half-life in surface soil of 9–15 years and in subsurface soil of 25–100 years (Paustenbach et al. 1992). Even though levels have decreased, dioxins and furans are still present in the environment from historical releases and, in certain cases, industrial or agricultural incidents (EPA, 2019; WHO, 2016).

The primary route of exposure in the general population is the ingestion of foods, including breast milk (Health Canada, 2006). Because of their lipophilic properties, higher levels of dioxins and furans are generally found in certain fat-containing foods, such as meats, dairy products, eggs and fish (ATSDR, 1998; Consonni et al., 2012; EPA, 2019). Dioxin and furan exposure may also occur through air, drinking water and consumer products; however, exposure from these sources is very low (ATSDR, 1994; ATSDR, 1998).

Although dioxins and furans are readily absorbed following oral exposure, the rate of absorption is specific to each congener and the vehicle used (ATSDR, 1994; ATSDR, 1998). Once in the bloodstream, these compounds are carried by serum lipids and lipoproteins. They are stored mainly in lipid-rich tissues, with the highest concentrations found in the liver, adipose tissue, skin and muscle (ATSDR, 1994; ATSDR, 1998; Aylward et al., 2008). Data from experimental studies demonstrated that fetuses might be exposed to dioxins and furans via the placenta (ATSDR, 1994; ATSDR, 1998; Lampa et al., 2018). The extent of metabolism and accumulation depend on the number of chlorine atom substitutions, with more chlorinated substances undergoing greater accumulation (ATSDR, 1994; ATSDR, 1998). Dioxins and furans can be measured in breast milk, adipose tissue and blood or its components, including whole blood, plasma and serum (Patterson et al., 1988). These chemicals are slowly excreted from the body, mainly via feces, but can also be excreted efficiently through breast milk. Estimated half-lives differ between congeners, and range from 2–15 years in adults (ATSDR, 1994; ATSDR, 1998; Aylward et al., 2008). Serum levels of dioxins and furans are used to assess human exposures to these chemicals in the general population (Aylward et al., 2008).

Most, if not all, toxic effects of dioxins and furans are mediated through activation of the aryl hydrocarbon receptor. Acute ingestion of dioxins and furans induces hepatotoxicity and chloracne, characterized by persistent skin lesions (Marinković et al., 2010; WHO, 2010). Chronic exposure can lead to reproductive, developmental and neurodevelopmental effects as well as endocrine and immune system toxicity (WHO, 2010). The International Agency for Research on Cancer (2012) has classified TCDD and 2,3,4,7,8-PeCDF as Group 1 (carcinogenic to humans) and other dioxins and furans as Group 3 (not classifiable as to their carcinogenicity to humans). The toxicities of dioxin and furan mixtures can be expressed in terms of toxic equivalents (TEQs), which can be used to evaluate the human health risks posed by these complex mixtures (Consonni et al., 2012; WHO, 2010). An overview of the TEQ approach is provided in Appendix B.

Dioxins and furans are listed on Schedule 1, List of Toxic Substances, of the Canadian Environmental Protection Act, 1999 (CEPA 1999). They are also classified as persistent organic pollutants by the Stockholm Convention on Persistent Organic Pollutants (Canada, 1999; Environment Canada, 2013a; Environment Canada, 2013b; UNEP, 2008). The Government of Canada considers dioxins and furans to be persistent, bioaccumulative and toxic; as such, they are targeted for full life cycle management (Track 2 substances) (Environment Canada, 2013a; Environment Canada, 2013b; Environment Canada and Health Canada, 1990). Risk management actions under CEPA 1999 have been developed to control and, if possible, eliminate releases of these substances into the environment (Health Canada, 2006). These actions include: Canada-wide standards to minimize the release of dioxins and furans from municipal solid waste and hazardous waste incinerators, coastal pulp and paper boilers, iron sintering plants and electric arc furnaces; regulations requiring the virtual elimination of dioxin and furan release from pulp mills; and multi-pollutant approaches for other sectors, including base metals smelting, diesel fuel combustion, electric power generation and wood treatment. TCDD is also a prohibited ingredient on the List of Prohibited and Restricted Cosmetic Ingredients (more commonly referred to as the Cosmetic Ingredient Hotlist, or simply the Hotlist), an administrative tool that Health Canada uses to communicate to manufacturers and others that certain substances, when present in a cosmetic, may not comply with the requirements of the Food and Drugs Act or the Cosmetic Regulations (Health Canada, 2019). This list also provides limits for other dioxins and furans that might be present as impurities during triclosan manufacturing (Health Canada, 2019). Dioxins and furans are analyzed as part of Health Canada's ongoing Total Diet Study surveys (Health Canada, 2016) as well by the Canadian Food Inspection Agency as part of its ongoing monitoring and surveillance activities. These survey activities demonstrate that dioxin and furan concentrations in foods sold in Canada have decreased in the past 25 years. Internationally, Canada is working with the United Nations to reduce the unintentional releases of dioxins and furans through the Convention on Long-Range Transboundary Air Pollution and the Stockholm Convention on Persistent Organic Pollutants.

Dioxins and furans have been measured in pooled blood samples from pregnant women during regional biomonitoring studies conducted in Alberta, northern Saskatchewan and Nunavik. In 2005, the Alberta Biomonitoring Program conducted a biomonitoring study of pregnant women living in Alberta (Alberta Health and Wellness, 2008). Serum samples from 28,484 individuals were combined into 158 pools. Detectable levels were reported for three dioxin congeners (1,2,3,6,7,8-HxCDD, HpCDD and OCDD) and six furan congeners (1,2,3,7,8- PeCDF, 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF, 1,2,3,4,6,7,8-HpCDF and OCDF). HpCDD and OCDD were the most highly detected congeners, with mean concentrations ranging from 5.5–55 pg/g lipid for HpCDD and from 5.3–280 pg/g lipid for OCDD. The Northern Saskatchewan Biomonitoring Study was carried out from 2011–2013 in pregnant women living in northern Saskatchewan (Saskatchewan Ministry of Health, 2019). Serum samples from 841 individuals were combined into six pools. Detectable levels were reported for three dioxin congeners (1,2,3,6,7,8-HxCDD, HpCDD and OCDD) and three furan congeners (1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF and 1,2,3,4,6,7,8-HpCDF). As in the other regional biomonitoring studies, HpCDD and OCDD were the most highly detected congeners. Concentrations ranged from 8.9–16 pg/g lipid for HpCDD and from 90–110 pg/g lipid for OCDD. In 2013, a study of emerging Arctic contaminants was conducted in Nunavik under the Arctic Monitoring and Assessment Programme (AMAP) MercuNorth Project (Caron et al., 2019). Five pools of plasma samples from 78 pregnant women were analyzed for dioxins and furans. Detectable levels were reported for three dioxin congeners (1,2,3,6,7,8-HxCDD, HpCDD and OCDD) and two furan congeners (2,3,4,7,8-PeCDF and 1,2,3,4,6,7,8-HpCDF). HpCDD and OCDD were the most highly detected congeners, with geometric mean concentrations of 5.33 pg/g lipid for HpCDD and 60.18 pg/g lipid for OCDD.

Seventeen dioxin and furan congeners (Table 7.1.1 and 7.1.2) were analyzed in pooled serum samples of CHMS participants aged 6–79 in cycle 1 (2007–2009) and aged 3–79 in cycles 3 (2012–2013), 4 (2014–2015) and 5 (2016–2017). Data from these cycles are presented as pg/g lipid and pg/g serum. Finding a measurable amount of dioxin and furan congeners in serum is an indicator of exposure to dioxins and furans. It does not necessarily mean that an adverse health effect will occur.

Rawn et al. (2012) published dioxin and furan data from pooled serum samples collected in cycle 1 of the CHMS. These previously published results were generated using a different statistical approach. As a result, they are not directly comparable with the data presented in this report.

Table 7.1.3
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	2.1	NC-L	NC-L
4 (2014–2015)	67	<LOD	1.9	NC-L	NC-L
5 (2016–2017)	67	<LOD	1.3	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	2.8	0.91	13
3 (2012–2013)	59	<LOD	2.1	NC-L	NC-L
4 (2014–2015)	61	<LOD	1.9	NC-L	NC-L
5 (2016–2017)	61	<LOD	1.3	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	2.8	0.93	34
3 (2012–2013)	29	<LOD	2.1	NC-L	NC-L
4 (2014–2015)	31	<LOD	1.9	NC-L	NC-L
5 (2016–2017)	31	<LOD	1.3	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	2.2	0.90	8
3 (2012–2013)	30	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	30	<LOD	1.7	NC-L	NC-L
5 (2016–2017)	30	<LOD	<LOD	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	1.8	0.74	46
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.5	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	1.9	0.66	20
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	1.9	1.0	36
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	1.7	NC-L	NC-L
5 (2016–2017)	13	<LOD	<LOD	NC-L	NC-L
40–59 years
1 (2007–2009)	14	0.17	2.2	0.64	16
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.3	0.70	14
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
60–79 years
1 (2007–2009)	12	0.51	2.8	1.5	10
3 (2012–2013)	12	<LOD	2.1	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.9	NC-M	NC-M
5 (2016–2017)	12	<LOD	1.3	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.1, 0.65, 0.27 and 0.38 pg/g lipid, respectively
Table 7.1.3 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.3 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.4
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.013	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.0089	NC-L	NC-L
5 (2016–2017)	67	<LOD	0.0074	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.020	0.0058	11
3 (2012–2013)	59	<LOD	0.013	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.0089	NC-L	NC-L
5 (2016–2017)	61	<LOD	0.0074	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.020	0.0060	31
3 (2012–2013)	29	<LOD	0.013	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.0089	NC-L	NC-L
5 (2016–2017)	31	<LOD	0.0074	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.016	0.0056	11
3 (2012–2013)	30	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.0080	NC-L	NC-L
5 (2016–2017)	30	<LOD	<LOD	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	0.0092	0.0038	46
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0068	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.010	0.0033	21
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.011	0.0061	33
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.0075	NC-L	NC-L
5 (2016–2017)	13	<LOD	<LOD	NC-L	NC-L
40–59 years
1 (2007–2009)	14	0.0011	0.016	0.0045	15
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0060	0.0041	31
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
60–79 years
1 (2007–2009)	12	0.0034	0.020	0.010	10
3 (2012–2013)	12	<LOD	0.013	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0089	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.0074	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.3.
Table 7.1.4 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.3 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.5
1,2,3,7,8-Pentachlorodibenzo-p-dioxin (PeCDD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	13	NC-L	NC-L
4 (2014–2015)	67	<LOD	9.0	3.7	24
5 (2016–2017)	67	<LOD	5.9	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	7.8	3.1	3
3 (2012–2013)	59	<LOD	13	NC-L	NC-L
4 (2014–2015)	61	<LOD	9.0	3.8	24
5 (2016–2017)	61	<LOD	5.9	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	7.8	3.0	8
3 (2012–2013)	29	<LOD	13	NC-L	NC-L
4 (2014–2015)	31	<LOD	9.0	3.5	22
5 (2016–2017)	31	<LOD	5.9	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	0.81	6.4	3.2	2
3 (2012–2013)	30	<LOD	12	NC-L	NC-L
4 (2014–2015)	30	<LOD	8.2	NC-M	NC-M
5 (2016–2017)	30	<LOD	5.7	2.8	7
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	6.1	1.1	39
4 (2014–2015)	6	<LOD	3.3	1.7	65
5 (2016–2017)	6	<LOD	4.3	NC-L	NC-L
6–11 years
1 (2007–2009)	10	0.81	2.8	2.3	11
3 (2012–2013)	11	<LOD	3.0	NC-L	NC-L
4 (2014–2015)	12	<LOD	4.7	NC-L	NC-L
5 (2016–2017)	12	<LOD	5.7	NC-L	NC-L
12–19 years
1 (2007–2009)	10	1.3	2.4	1.8	15
3 (2012–2013)	12	<LOD	12	NC-L	NC-L
4 (2014–2015)	12	<LOD	3.3	NC-L	NC-L
5 (2016–2017)	12	<LOD	3.6	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	2.7	2.2	3
3 (2012–2013)	12	<LOD	13	NC-L	NC-L
4 (2014–2015)	13	1.8	7.1	2.8	25
5 (2016–2017)	13	<LOD	4.2	NC-L	NC-L
40–59 years
1 (2007–2009)	14	3.0	5.1	3.7	1
3 (2012–2013)	12	<LOD	9.5	NC-L	NC-L
4 (2014–2015)	12	2.7	9.0	5.2	41
5 (2016–2017)	12	<LOD	4.2	NC-M	NC-M
60–79 years
1 (2007–2009)	12	1.3	7.8	4.6	23
3 (2012–2013)	12	<LOD	11	4.2	16
4 (2014–2015)	12	<LOD	7.0	NC-M	NC-M
5 (2016–2017)	12	3.6	5.9	4.8	4
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.3, 0.75, 0.39 and 0.57 pg/g lipid, respectively.
Table 7.1.5 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.5 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.6
1,2,3,7,8-Pentachlorodibenzo-p-dioxin (PeCDD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.062	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.042	0.019	10
5 (2016–2017)	67	<LOD	0.034	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.054	0.020	2
3 (2012–2013)	59	<LOD	0.062	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.042	0.019	10
5 (2016–2017)	61	<LOD	0.034	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.054	0.020	9
3 (2012–2013)	29	<LOD	0.062	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.042	0.018	11
5 (2016–2017)	31	<LOD	0.034	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	0.0045	0.043	0.020	4
3 (2012–2013)	30	<LOD	0.058	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.038	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.025	0.014	1
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.024	0.0046	32
4 (2014–2015)	6	<LOD	0.015	0.0085	64
5 (2016–2017)	6	<LOD	0.018	NC-L	NC-L
6–11 years
1 (2007–2009)	10	0.0045	0.015	0.012	12
3 (2012–2013)	11	<LOD	0.014	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.021	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.021	NC-L	NC-L
12–19 years
1 (2007–2009)	10	0.0068	0.012	0.0093	15
3 (2012–2013)	12	<LOD	0.043	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.013	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.012	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.017	0.013	1
3 (2012–2013)	12	<LOD	0.062	NC-L	NC-L
4 (2014–2015)	13	0.010	0.026	0.014	9
5 (2016–2017)	13	<LOD	0.024	NC-L	NC-L
40–59 years
1 (2007–2009)	14	0.020	0.036	0.026	1
3 (2012–2013)	12	<LOD	0.057	NC-L	NC-L
4 (2014–2015)	12	0.017	0.042	0.028	25
5 (2016–2017)	12	<LOD	0.025	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.010	0.054	0.032	22
3 (2012–2013)	12	<LOD	0.058	0.024	13
4 (2014–2015)	12	<LOD	0.034	NC-M	NC-M
5 (2016–2017)	12	0.018	0.034	0.026	1
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.5.
Table 7.1.6 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.6 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.7
1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (HxCDD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	6.5	2.6	1
4 (2014–2015)	67	<LOD	8.1	NC-M	NC-M
5 (2016–2017)	67	<LOD	10	2.5	8
Total, 6–79 years
1 (2007–2009)	59	<LOD	5.3	2.7	2
3 (2012–2013)	59	<LOD	6.5	2.7	0
4 (2014–2015)	61	<LOD	8.1	NC-M	NC-M
5 (2016–2017)	61	<LOD	10	2.6	8
Females, 6–79 years
1 (2007–2009)	30	<LOD	5.0	2.4	6
3 (2012–2013)	29	<LOD	6.5	2.8	7
4 (2014–2015)	31	<LOD	8.1	NC-M	NC-M
5 (2016–2017)	31	<LOD	4.2	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	5.3	3.0	8
3 (2012–2013)	30	<LOD	5.7	2.5	8
4 (2014–2015)	30	0.70	5.8	NC-M	NC-M
5 (2016–2017)	30	<LOD	10	2.6	14
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	1.0	2.6	2.0	20
4 (2014–2015)	6	<LOD	2.1	1.3	33
5 (2016–2017)	6	<LOD	2.7	1.6	39
6–11 years
1 (2007–2009)	10	<LOD	2.8	1.7	10
3 (2012–2013)	11	<LOD	2.5	NC-L	NC-L
4 (2014–2015)	12	<LOD	3.7	NC-M	NC-M
5 (2016–2017)	12	<LOD	3.4	2.0	22
12–19 years
1 (2007–2009)	10	<LOD	2.1	NC-L	NC-L
3 (2012–2013)	12	<LOD	6.1	NC-M	NC-M
4 (2014–2015)	12	1.2	4.4	NC-M	NC-M
5 (2016–2017)	12	<LOD	2.6	1.8	8
20–39 years
1 (2007–2009)	13	1.5	3.4	2.4	1
3 (2012–2013)	12	<LOD	4.0	2.9	11
4 (2014–2015)	13	1.2	4.4	1.9	29
5 (2016–2017)	13	1.3	3.6	2.6	12
40–59 years
1 (2007–2009)	14	1.9	4.6	3.1	13
3 (2012–2013)	12	<LOD	5.7	2.1	18
4 (2014–2015)	12	1.9	5.8	3.3	32
5 (2016–2017)	12	1.0	2.2	NC-M	NC-M
60–79 years
1 (2007–2009)	12	1.8	5.3	3.8	16
3 (2012–2013)	12	3.0	6.5	4.2	6
4 (2014–2015)	12	2.7	8.1	NC-M	NC-M
5 (2016–2017)	12	2.1	10	4.3	15
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.7, 0.74, 0.39 and 0.49 pg/g lipid, respectively.
Table 7.1.7 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.7 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.8
1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (HxCDD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.039	0.014	2
4 (2014–2015)	67	<LOD	0.048	NC-M	NC-M
5 (2016–2017)	67	<LOD	0.049	0.013	4
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.036	0.017	3
3 (2012–2013)	59	<LOD	0.039	0.014	2
4 (2014–2015)	61	<LOD	0.048	NC-M	NC-M
5 (2016–2017)	61	<LOD	0.049	0.013	3
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.035	0.015	5
3 (2012–2013)	29	<LOD	0.039	0.015	5
4 (2014–2015)	31	<LOD	0.048	NC-M	NC-M
5 (2016–2017)	31	<LOD	0.024	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.036	0.019	10
3 (2012–2013)	30	<LOD	0.032	0.014	8
4 (2014–2015)	30	0.0031	0.027	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.049	0.013	7
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.0048	0.010	0.0088	12
4 (2014–2015)	6	<LOD	0.010	0.0064	34
5 (2016–2017)	6	<LOD	0.010	0.0069	43
6–11 years
1 (2007–2009)	10	<LOD	0.015	0.0089	11
3 (2012–2013)	11	<LOD	0.011	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.017	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.012	0.0075	18
12–19 years
1 (2007–2009)	10	<LOD	0.011	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.024	NC-M	NC-M
4 (2014–2015)	12	0.0048	0.022	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.0094	0.0070	2
20–39 years
1 (2007–2009)	13	0.0087	0.021	0.014	2
3 (2012–2013)	12	<LOD	0.021	0.015	18
4 (2014–2015)	13	0.0077	0.019	0.0096	13
5 (2016–2017)	13	0.0057	0.017	0.012	8
40–59 years
1 (2007–2009)	14	0.013	0.032	0.021	14
3 (2012–2013)	12	<LOD	0.032	0.012	18
4 (2014–2015)	12	0.012	0.027	0.018	14
5 (2016–2017)	12	0.0059	0.013	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.014	0.036	0.026	16
3 (2012–2013)	12	0.017	0.039	0.024	6
4 (2014–2015)	12	0.012	0.048	NC-M	NC-M
5 (2016–2017)	12	0.0097	0.049	0.023	10
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.7.
Table 7.1.8 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.8 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.9
1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (HxCDD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	40	14	5
4 (2014–2015)	67	<LOD	49	NC-M	NC-M
5 (2016–2017)	67	4.2	32	13	1
Total, 6–79 years
1 (2007–2009)	59	3.0	51	21	2
3 (2012–2013)	59	<LOD	40	14	5
4 (2014–2015)	61	<LOD	49	NC-M	NC-M
5 (2016–2017)	61	4.2	32	13	1
Females, 6–79 years
1 (2007–2009)	30	5.5	51	20	7
3 (2012–2013)	29	<LOD	40	15	5
4 (2014–2015)	31	<LOD	49	NC-M	NC-M
5 (2016–2017)	31	4.2	32	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	3.0	50	23	9
3 (2012–2013)	30	4.1	36	13	7
4 (2014–2015)	30	4.4	39	NC-M	NC-M
5 (2016–2017)	30	4.6	30	13	0
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	8.0	13	9.9	4
4 (2014–2015)	6	7.0	11	8.6	8
5 (2016–2017)	6	6.9	10	8.3	7
6–11 years
1 (2007–2009)	10	3.0	11	8.7	9
3 (2012–2013)	11	2.7	13	7.7	1
4 (2014–2015)	12	<LOD	8.2	NC-M	NC-M
5 (2016–2017)	12	4.6	10	7.2	17
12–19 years
1 (2007–2009)	10	5.5	9.6	7.6	3
3 (2012–2013)	12	3.2	11	NC-M	NC-M
4 (2014–2015)	12	4.8	7.2	NC-M	NC-M
5 (2016–2017)	12	4.2	7.4	6.0	6
20–39 years
1 (2007–2009)	13	12	23	15	10
3 (2012–2013)	12	<LOD	14	9.7	12
4 (2014–2015)	13	6.1	12	8.0	19
5 (2016–2017)	13	4.7	8.6	7.2	4
40–59 years
1 (2007–2009)	14	23	50	27	9
3 (2012–2013)	12	11	19	13	5
4 (2014–2015)	12	12	22	18	13
5 (2016–2017)	12	8.3	14	NC-M	NC-M
60–79 years
1 (2007–2009)	12	5.8	51	37	22
3 (2012–2013)	12	23	40	29	2
4 (2014–2015)	12	16	49	NC-M	NC-M
5 (2016–2017)	12	22	32	27	7
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.7, 0.86, 0.40 and 0.49 pg/g lipid, respectively.
Table 7.1.9 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.9 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.10
1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (HxCDD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.24	0.077	4
4 (2014–2015)	67	<LOD	0.24	NC-M	NC-M
5 (2016–2017)	67	0.017	0.18	0.066	2
Total, 6–79 years
1 (2007–2009)	59	0.017	0.37	0.14	2
3 (2012–2013)	59	<LOD	0.24	0.078	5
4 (2014–2015)	61	<LOD	0.24	NC-M	NC-M
5 (2016–2017)	61	0.017	0.18	0.068	2
Females, 6–79 years
1 (2007–2009)	30	0.029	0.35	0.13	7
3 (2012–2013)	29	<LOD	0.24	0.085	4
4 (2014–2015)	31	<LOD	0.24	NC-M	NC-M
5 (2016–2017)	31	0.017	0.18	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	0.017	0.37	0.15	11
3 (2012–2013)	30	0.018	0.18	0.071	6
4 (2014–2015)	30	0.019	0.20	NC-M	NC-M
5 (2016–2017)	30	0.018	0.15	0.064	6
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.032	0.062	0.044	5
4 (2014–2015)	6	0.035	0.049	0.042	9
5 (2016–2017)	6	0.031	0.040	0.035	2
6–11 years
1 (2007–2009)	10	0.017	0.061	0.046	10
3 (2012–2013)	11	0.013	0.062	0.035	6
4 (2014–2015)	12	<LOD	0.035	NC-M	NC-M
5 (2016–2017)	12	0.017	0.034	0.025	15
12–19 years
1 (2007–2009)	10	0.029	0.048	0.039	3
3 (2012–2013)	12	0.014	0.044	NC-M	NC-M
4 (2014–2015)	12	0.021	0.030	NC-M	NC-M
5 (2016–2017)	12	0.017	0.030	0.023	12
20–39 years
1 (2007–2009)	13	0.071	0.14	0.089	12
3 (2012–2013)	12	<LOD	0.073	0.050	5
4 (2014–2015)	13	0.032	0.053	0.040	3
5 (2016–2017)	13	0.022	0.047	0.034	1
40–59 years
1 (2007–2009)	14	0.16	0.37	0.19	9
3 (2012–2013)	12	0.057	0.11	0.078	5
4 (2014–2015)	12	0.072	0.11	0.098	6
5 (2016–2017)	12	0.049	0.083	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.044	0.35	0.25	22
3 (2012–2013)	12	0.12	0.24	0.17	2
4 (2014–2015)	12	0.072	0.24	NC-M	NC-M
5 (2016–2017)	12	0.11	0.18	0.15	3
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.9.
Table 7.1.10 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.10 footnote a Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.11
1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (HxCDD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	9.3	NC-L	NC-L
4 (2014–2015)	67	<LOD	7.3	NC-M	NC-M
5 (2016–2017)	67	<LOD	5.5	3.1	4
Total, 6–79 years
1 (2007–2009)	59	<LOD	7.1	3.2	10
3 (2012–2013)	59	<LOD	9.3	NC-L	NC-L
4 (2014–2015)	61	<LOD	7.3	NC-M	NC-M
5 (2016–2017)	61	<LOD	5.5	3.1	4
Females, 6–79 years
1 (2007–2009)	30	<LOD	7.1	3.6	5
3 (2012–2013)	29	<LOD	8.9	NC-L	NC-L
4 (2014–2015)	31	<LOD	7.2	NC-M	NC-M
5 (2016–2017)	31	<LOD	5.1	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	4.9	2.8	16
3 (2012–2013)	30	<LOD	9.3	NC-L	NC-L
4 (2014–2015)	30	<LOD	7.3	NC-M	NC-M
5 (2016–2017)	30	<LOD	5.5	3.0	10
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	2.6	1.6	46
4 (2014–2015)	6	<LOD	3.5	2.2	21
5 (2016–2017)	6	<LOD	4.5	3.3	1
6–11 years
1 (2007–2009)	10	<LOD	4.0	2.6	26
3 (2012–2013)	11	<LOD	4.3	NC-L	NC-L
4 (2014–2015)	12	<LOD	7.3	NC-M	NC-M
5 (2016–2017)	12	<LOD	5.5	3.3	34
12–19 years
1 (2007–2009)	10	<LOD	3.4	2.6	10
3 (2012–2013)	12	<LOD	5.5	NC-L	NC-L
4 (2014–2015)	12	<LOD	3.5	NC-M	NC-M
5 (2016–2017)	12	<LOD	4.8	2.5	34
20–39 years
1 (2007–2009)	13	<LOD	3.9	2.6	12
3 (2012–2013)	12	<LOD	9.3	NC-L	NC-L
4 (2014–2015)	13	2.0	4.4	2.6	19
5 (2016–2017)	13	2.3	4.6	3.1	1
40–59 years
1 (2007–2009)	14	3.0	4.8	3.8	2
3 (2012–2013)	12	<LOD	8.9	NC-L	NC-L
4 (2014–2015)	12	<LOD	4.0	2.1	33
5 (2016–2017)	12	1.1	3.6	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	7.1	3.8	50
3 (2012–2013)	12	<LOD	6.5	4.0	0
4 (2014–2015)	12	<LOD	7.2	NC-M	NC-M
5 (2016–2017)	12	2.0	5.2	4.5	1
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 2.1, 0.79, 0.38 and 0.49 pg/g lipid, respectively.
Table 7.1.11 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.11 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.12
1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (HxCDD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.050	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.035	NC-M	NC-M
5 (2016–2017)	67	<LOD	0.029	0.016	8
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.051	0.020	10
3 (2012–2013)	59	<LOD	0.050	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.035	NC-M	NC-M
5 (2016–2017)	61	<LOD	0.029	0.016	8
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.051	0.023	6
3 (2012–2013)	29	<LOD	0.050	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.035	NC-M	NC-M
5 (2016–2017)	31	<LOD	0.029	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.033	0.018	15
3 (2012–2013)	30	<LOD	0.046	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.033	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.027	0.015	16
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.012	0.0073	53
4 (2014–2015)	6	<LOD	0.018	0.011	20
5 (2016–2017)	6	<LOD	0.022	0.014	8
6–11 years
1 (2007–2009)	10	<LOD	0.020	0.014	26
3 (2012–2013)	11	<LOD	0.019	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.033	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.020	0.012	33
12–19 years
1 (2007–2009)	10	<LOD	0.017	0.013	11
3 (2012–2013)	12	<LOD	0.024	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.015	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.019	0.0097	29
20–39 years
1 (2007–2009)	13	<LOD	0.023	0.015	10
3 (2012–2013)	12	<LOD	0.046	NC-L	NC-L
4 (2014–2015)	13	0.011	0.018	0.013	2
5 (2016–2017)	13	0.010	0.027	0.014	4
40–59 years
1 (2007–2009)	14	0.021	0.031	0.026	1
3 (2012–2013)	12	<LOD	0.050	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.022	0.013	48
5 (2016–2017)	12	0.0059	0.020	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	0.051	0.026	49
3 (2012–2013)	12	<LOD	0.039	0.023	0
4 (2014–2015)	12	<LOD	0.035	NC-M	NC-M
5 (2016–2017)	12	0.0092	0.029	0.024	3
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.11.
Table 7.1.12 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.12 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.13
1,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin (HpCDD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	5.1	34	18	3
4 (2014–2015)	67	7.0	32	NC-M	NC-M
5 (2016–2017)	67	7.3	30	17	4
Total, 6–79 years
1 (2007–2009)	59	3.3	46	22	1
3 (2012–2013)	59	5.1	34	18	2
4 (2014–2015)	61	7.0	32	NC-M	NC-M
5 (2016–2017)	61	7.4	30	18	4
Females, 6–79 years
1 (2007–2009)	30	7.7	46	22	5
3 (2012–2013)	29	5.7	34	19	5
4 (2014–2015)	31	7.4	32	18	10
5 (2016–2017)	31	8.7	26	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	3.3	35	22	2
3 (2012–2013)	30	5.1	25	17	1
4 (2014–2015)	30	7.0	24	NC-M	NC-M
5 (2016–2017)	30	7.4	30	16	2
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	8.6	16	12	25
4 (2014–2015)	6	9.0	13	11	7
5 (2016–2017)	6	7.3	14	12	8
6–11 years
1 (2007–2009)	10	3.3	19	12	18
3 (2012–2013)	11	5.7	18	10	29
4 (2014–2015)	12	7.0	14	NC-M	NC-M
5 (2016–2017)	12	7.4	20	13	29
12–19 years
1 (2007–2009)	10	7.7	17	13	5
3 (2012–2013)	12	5.1	19	NC-M	NC-M
4 (2014–2015)	12	7.4	14	NC-M	NC-M
5 (2016–2017)	12	8.7	15	14	2
20–39 years
1 (2007–2009)	13	16	25	19	8
3 (2012–2013)	12	11	25	18	6
4 (2014–2015)	13	9.0	21	14	19
5 (2016–2017)	13	13	30	18	3
40–59 years
1 (2007–2009)	14	19	34	26	10
3 (2012–2013)	12	12	25	16	9
4 (2014–2015)	12	12	23	17	17
5 (2016–2017)	12	10	23	NC-M	NC-M
60–79 years
1 (2007–2009)	12	13	46	31	20
3 (2012–2013)	12	19	34	26	8
4 (2014–2015)	12	18	32	NC-M	NC-M
5 (2016–2017)	12	15	30	23	4
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.7, 0.53, 0.26 and 0.43 pg/g lipid, respectively.
Table 7.1.13 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.13 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.14
1,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin (HpCDD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	0.024	0.20	0.096	3
4 (2014–2015)	67	0.032	0.16	NC-M	NC-M
5 (2016–2017)	67	0.027	0.18	0.088	7
Total, 6–79 years
1 (2007–2009)	59	0.018	0.32	0.14	0
3 (2012–2013)	59	0.024	0.20	0.098	3
4 (2014–2015)	61	0.032	0.16	NC-M	NC-M
5 (2016–2017)	61	0.027	0.18	0.089	7
Females, 6–79 years
1 (2007–2009)	30	0.042	0.32	0.14	4
3 (2012–2013)	29	0.027	0.20	0.10	6
4 (2014–2015)	31	0.032	0.16	0.094	1
5 (2016–2017)	31	0.033	0.15	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	0.018	0.24	0.14	4
3 (2012–2013)	30	0.024	0.15	0.093	1
4 (2014–2015)	30	0.032	0.13	NC-M	NC-M
5 (2016–2017)	30	0.027	0.18	0.082	7
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.041	0.066	0.054	17
4 (2014–2015)	6	0.041	0.064	0.056	6
5 (2016–2017)	6	0.031	0.056	0.049	4
6–11 years
1 (2007–2009)	10	0.018	0.10	0.064	19
3 (2012–2013)	11	0.027	0.072	0.047	25
4 (2014–2015)	12	0.032	0.063	NC-M	NC-M
5 (2016–2017)	12	0.027	0.067	0.046	27
12–19 years
1 (2007–2009)	10	0.042	0.085	0.064	5
3 (2012–2013)	12	0.024	0.081	NC-M	NC-M
4 (2014–2015)	12	0.032	0.069	NC-M	NC-M
5 (2016–2017)	12	0.036	0.060	0.052	4
20–39 years
1 (2007–2009)	13	0.094	0.16	0.11	6
3 (2012–2013)	12	0.057	0.13	0.096	12
4 (2014–2015)	13	0.055	0.084	0.069	3
5 (2016–2017)	13	0.060	0.18	0.086	7
40–59 years
1 (2007–2009)	14	0.13	0.22	0.18	11
3 (2012–2013)	12	0.062	0.15	0.095	9
4 (2014–2015)	12	0.075	0.12	0.095	1
5 (2016–2017)	12	0.057	0.14	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.099	0.32	0.21	19
3 (2012–2013)	12	0.11	0.20	0.15	8
4 (2014–2015)	12	0.081	0.16	NC-M	NC-M
5 (2016–2017)	12	0.087	0.15	0.12	1
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.13.
Table 7.1.14 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.14 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.15
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (OCDD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	310	130	5
4 (2014–2015)	67	55	300	120	10
5 (2016–2017)	67	59	220	120	3
Total, 6–79 years
1 (2007–2009)	59	2.3	360	160	5
3 (2012–2013)	59	61	310	130	5
4 (2014–2015)	61	55	300	120	10
5 (2016–2017)	61	59	220	120	3
Females, 6–79 years
1 (2007–2009)	30	63	360	180	4
3 (2012–2013)	29	61	310	150	5
4 (2014–2015)	31	55	300	140	9
5 (2016–2017)	31	59	220	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	2.3	220	130	6
3 (2012–2013)	30	72	210	120	4
4 (2014–2015)	30	55	180	NC-M	NC-M
5 (2016–2017)	30	65	140	100	3
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	91	78	10
4 (2014–2015)	6	66	86	77	4
5 (2016–2017)	6	59	100	76	4
6–11 years
1 (2007–2009)	10	2.3	130	89	25
3 (2012–2013)	11	64	110	85	1
4 (2014–2015)	12	58	100	NC-M	NC-M
5 (2016–2017)	12	61	140	93	13
12–19 years
1 (2007–2009)	10	79	120	96	4
3 (2012–2013)	12	61	110	NC-M	NC-M
4 (2014–2015)	12	55	82	NC-M	NC-M
5 (2016–2017)	12	59	140	86	8
20–39 years
1 (2007–2009)	13	82	210	130	12
3 (2012–2013)	12	84	170	110	16
4 (2014–2015)	13	55	150	91	17
5 (2016–2017)	13	74	170	110	8
40–59 years
1 (2007–2009)	14	130	260	190	3
3 (2012–2013)	12	97	210	130	0
4 (2014–2015)	12	77	180	120	14
5 (2016–2017)	12	69	140	NC-M	NC-M
60–79 years
1 (2007–2009)	12	63	360	220	24
3 (2012–2013)	12	140	310	220	7
4 (2014–2015)	12	140	300	NC-M	NC-M
5 (2016–2017)	12	120	220	160	0
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 4.4, 3.4, 0.69 and 1.1 pg/g lipid, respectively.
Table 7.1.15 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.15 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.16
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (OCDD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV ^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	1.9	0.73	6
4 (2014–2015)	67	0.23	1.4	0.61	2
5 (2016–2017)	67	0.24	1.1	0.59	6
Total, 6–79 years
1 (2007–2009)	59	0.013	2.5	1.0	4
3 (2012–2013)	59	0.29	1.9	0.74	6
4 (2014–2015)	61	0.23	1.4	0.61	2
5 (2016–2017)	61	0.24	1.1	0.59	6
Females, 6–79 years
1 (2007–2009)	30	0.43	2.5	1.2	4
3 (2012–2013)	29	0.29	1.9	0.84	6
4 (2014–2015)	31	0.23	1.4	0.72	1
5 (2016–2017)	31	0.24	1.1	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	0.013	1.5	0.85	5
3 (2012–2013)	30	0.33	1.3	0.64	5
4 (2014–2015)	30	0.27	0.99	NC-M	NC-M
5 (2016–2017)	30	0.26	0.82	0.49	3
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.37	0.34	2
4 (2014–2015)	6	0.28	0.42	0.38	3
5 (2016–2017)	6	0.25	0.36	0.32	1
6–11 years
1 (2007–2009)	10	0.013	0.72	0.47	27
3 (2012–2013)	11	0.33	0.48	0.39	4
4 (2014–2015)	12	0.24	0.41	NC-M	NC-M
5 (2016–2017)	12	0.26	0.37	0.32	9
12–19 years
1 (2007–2009)	10	0.43	0.59	0.49	5
3 (2012–2013)	12	0.29	0.46	NC-M	NC-M
4 (2014–2015)	12	0.23	0.36	NC-M	NC-M
5 (2016–2017)	12	0.24	0.45	0.32	1
20–39 years
1 (2007–2009)	13	0.50	1.3	0.79	9
3 (2012–2013)	12	0.41	0.95	0.59	22
4 (2014–2015)	13	0.34	0.56	0.46	1
5 (2016–2017)	13	0.38	0.77	0.50	12
40–59 years
1 (2007–2009)	14	0.86	1.9	1.3	3
3 (2012–2013)	12	0.58	1.3	0.77	0
4 (2014–2015)	12	0.46	0.90	0.66	3
5 (2016–2017)	12	0.39	0.82	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.48	2.5	1.5	24
3 (2012–2013)	12	0.78	1.9	1.3	6
4 (2014–2015)	12	0.66	1.4	NC-M	NC-M
5 (2016–2017)	12	0.64	1.1	0.88	4
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.15.
Table 7.1.16 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.16 footnote a Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.17
2,3,7,8-Tetrachlorodibenzofuran (TCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	2.0	NC-L	NC-L
4 (2014–2015)	67	<LOD	5.8	2.1	16
5 (2016–2017)	67	<LOD	4.5	1.1	8
Total, 6–79 years
1 (2007–2009)	59	<LOD	1.9	0.67	8
3 (2012–2013)	59	<LOD	2.0	NC-L	NC-L
4 (2014–2015)	61	<LOD	5.8	2.1	15
5 (2016–2017)	61	<LOD	4.5	1.1	7
Females, 6–79 years
1 (2007–2009)	30	<LOD	1.9	0.69	10
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	5.8	2.6	11
5 (2016–2017)	31	<LOD	4.5	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	1.4	0.65	5
3 (2012–2013)	30	<LOD	2.0	NC-L	NC-L
4 (2014–2015)	30	<LOD	5.8	NC-M	NC-M
5 (2016–2017)	30	<LOD	4.1	1.2	1
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	4.6	NC-L	NC-L
5 (2016–2017)	6	<LOD	2.6	1.7	13
6–11 years
1 (2007–2009)	10	<LOD	1.4	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	5.8	NC-L	NC-L
5 (2016–2017)	12	<LOD	3.8	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	1.3	0.61	44
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	1.1	2.8	NC-M	NC-M
5 (2016–2017)	12	<LOD	4.5	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	1.2	0.67	10
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	3.7	2.3	44
5 (2016–2017)	13	<LOD	2.7	1.3	22
40–59 years
1 (2007–2009)	14	0.026	1.4	0.73	21
3 (2012–2013)	12	<LOD	2.0	NC-L	NC-L
4 (2014–2015)	12	<LOD	5.8	2.7	0
5 (2016–2017)	12	<LOD	1.6	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	1.9	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	5.0	NC-M	NC-M
5 (2016–2017)	12	<LOD	2.1	1.5	11
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.3, 0.49, 0.19 and 0.27 pg/g lipid, respectively.
Table 7.1.17 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.17 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.18
2,3,7,8-Tetrachlorodibenzofuran (TCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.034	0.011	2
5 (2016–2017)	67	<LOD	0.019	0.0054	2
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.014	0.0042	6
3 (2012–2013)	59	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.034	0.011	0
5 (2016–2017)	61	<LOD	0.019	0.0054	1
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.014	0.0044	10
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.034	0.014	3
5 (2016–2017)	31	<LOD	0.019	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.0094	0.0040	2
3 (2012–2013)	30	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.026	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.016	0.0057	10
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	0.020	NC-L	NC-L
5 (2016–2017)	6	<LOD	0.012	0.0074	21
6–11 years
1 (2007–2009)	10	<LOD	0.0073	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.026	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.019	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.0064	0.0031	43
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	0.0049	0.014	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.016	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.0071	0.0039	13
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.016	0.011	30
5 (2016–2017)	13	<LOD	0.013	0.0062	15
40–59 years
1 (2007–2009)	14	0.00019	0.0094	0.0050	20
3 (2012–2013)	12	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.034	0.015	17
5 (2016–2017)	12	<LOD	0.0083	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	0.014	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.027	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.011	0.0082	14
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.17.
Table 7.1.18 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.18 footnote a Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.19
1,2,3,7,8-Pentachlorodibenzofuran (PeCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	3.1	NC-L	NC-L
4 (2014–2015)	67	<LOD	5.6	1.3	33
5 (2016–2017)	67	<LOD	1.9	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	1.3	NC-L	NC-L
3 (2012–2013)	59	<LOD	3.1	NC-L	NC-L
4 (2014–2015)	61	<LOD	5.6	1.4	32
5 (2016–2017)	61	<LOD	1.9	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	1.2	NC-L	NC-L
3 (2012–2013)	29	<LOD	2.4	NC-L	NC-L
4 (2014–2015)	31	<LOD	4.3	1.2	8
5 (2016–2017)	31	<LOD	1.9	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	1.3	NC-L	NC-L
3 (2012–2013)	30	<LOD	3.1	NC-L	NC-L
4 (2014–2015)	30	<LOD	5.6	NC-M	NC-M
5 (2016–2017)	30	<LOD	1.4	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.49	NC-L	NC-L
4 (2014–2015)	6	<LOD	0.82	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	1.3	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	2.1	NC-L	NC-L
5 (2016–2017)	12	<LOD	1.5	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	1.2	NC-L	NC-L
3 (2012–2013)	12	<LOD	3.1	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.3	NC-M	NC-M
5 (2016–2017)	12	<LOD	1.9	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	1.1	NC-L	NC-L
3 (2012–2013)	12	<LOD	2.4	NC-L	NC-L
4 (2014–2015)	13	0.59	2.8	1.1	42
5 (2016–2017)	13	<LOD	1.4	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	1.0	NC-L	NC-L
3 (2012–2013)	12	<LOD	1.1	NC-L	NC-L
4 (2014–2015)	12	0.66	5.6	2.4	40
5 (2016–2017)	12	<LOD	1.4	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	1.1	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.31	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.4	NC-M	NC-M
5 (2016–2017)	12	<LOD	1.1	0.75	6
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.1, 0.33, 0.17 and 0.23 pg/g lipid, respectively.
Table 7.1.19 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.19 footnote a Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.20
1,2,3,7,8-Pentachlorodibenzofuran (PeCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.026	0.0067	19
5 (2016–2017)	67	<LOD	0.0077	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.0080	NC-L	NC-L
3 (2012–2013)	59	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.026	0.0069	18
5 (2016–2017)	61	<LOD	0.0077	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.0080	NC-L	NC-L
3 (2012–2013)	29	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.025	0.0065	5
5 (2016–2017)	31	<LOD	0.0068	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.0069	NC-L	NC-L
3 (2012–2013)	30	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.026	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.0077	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.0020	NC-L	NC-L
4 (2014–2015)	6	<LOD	0.0040	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	0.0065	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0095	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0060	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.0065	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0053	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.0068	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.0068	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.012	NC-L	NC-L
4 (2014–2015)	13	0.0034	0.012	0.0052	27
5 (2016–2017)	13	<LOD	0.0077	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.0069	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.0066	NC-L	NC-L
4 (2014–2015)	12	0.0040	0.026	0.012	24
5 (2016–2017)	12	<LOD	0.0074	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	0.0080	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.0016	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0074	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.0054	0.0040	1
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.19.
Table 7.1.20 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.20 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.21
2,3,4,7,8-Pentachlorodibenzofuran (PeCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%) ^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	15	3.7	22
4 (2014–2015)	67	<LOD	15	6.6	19
5 (2016–2017)	67	3.0	8.6	5.8	5
Total, 6–79 years
1 (2007–2009)	59	<LOD	8.8	4.2	15
3 (2012–2013)	59	<LOD	15	3.7	21
4 (2014–2015)	61	<LOD	15	6.7	19
5 (2016–2017)	61	3.0	8.6	5.8	5
Females, 6–79 years
1 (2007–2009)	30	<LOD	8.8	4.1	12
3 (2012–2013)	29	<LOD	14	3.3	26
4 (2014–2015)	31	<LOD	10	6.1	18
5 (2016–2017)	31	3.2	8.3	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	7.3	4.2	19
3 (2012–2013)	30	<LOD	15	4.1	17
4 (2014–2015)	30	<LOD	15	NC-M	NC-M
5 (2016–2017)	30	3.0	8.6	6.5	6
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	6.0	2.8	44
4 (2014–2015)	6	3.0	7.7	4.5	18
5 (2016–2017)	6	5.5	7.5	5.8	4
6–11 years
1 (2007–2009)	10	<LOD	3.6	2.2	38
3 (2012–2013)	11	<LOD	5.9	2.9	46
4 (2014–2015)	12	<LOD	6.3	NC-M	NC-M
5 (2016–2017)	12	3.0	7.8	5.7	11
12–19 years
1 (2007–2009)	10	1.8	4.6	3.0	2
3 (2012–2013)	12	<LOD	15	NC-L	NC-L
4 (2014–2015)	12	1.9	6.6	NC-M	NC-M
5 (2016–2017)	12	3.4	5.8	4.6	0
20–39 years
1 (2007–2009)	13	<LOD	6.8	3.4	33
3 (2012–2013)	12	<LOD	14	NC-L	NC-L
4 (2014–2015)	13	2.8	8.1	4.8	30
5 (2016–2017)	13	3.2	6.3	4.9	9
40–59 years
1 (2007–2009)	14	3.4	7.1	5.4	2
3 (2012–2013)	12	<LOD	9.7	4.7	37
4 (2014–2015)	12	4.8	15	8.7	25
5 (2016–2017)	12	3.8	8.0	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	8.8	4.7	55
3 (2012–2013)	12	6.8	11	8.2	4
4 (2014–2015)	12	6.4	10	NC-M	NC-M
5 (2016–2017)	12	6.4	8.6	7.7	1
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.3, 0.74, 0.27 and 0.39 pg/g lipid, respectively.
Table 7.1.21 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.21 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.22
2,3,4,7,8-Pentachlorodibenzofuran (PeCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.067	0.021	21
4 (2014–2015)	67	<LOD	0.069	0.034	6
5 (2016–2017)	67	0.011	0.046	0.029	8
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.063	0.027	14
3 (2012–2013)	59	<LOD	0.067	0.021	20
4 (2014–2015)	61	<LOD	0.069	0.035	6
5 (2016–2017)	61	0.011	0.046	0.029	8
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.063	0.027	11
3 (2012–2013)	29	<LOD	0.067	0.019	24
4 (2014–2015)	31	<LOD	0.059	0.032	9
5 (2016–2017)	31	0.012	0.044	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.051	0.026	17
3 (2012–2013)	30	<LOD	0.058	0.023	17
4 (2014–2015)	30	<LOD	0.069	NC-M	NC-M
5 (2016–2017)	30	0.011	0.046	0.032	11
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.025	0.013	51
4 (2014–2015)	6	0.015	0.033	0.022	17
5 (2016–2017)	6	0.022	0.027	0.025	9
6–11 years
1 (2007–2009)	10	<LOD	0.019	0.012	39
3 (2012–2013)	11	<LOD	0.026	0.013	43
4 (2014–2015)	12	<LOD	0.028	NC-M	NC-M
5 (2016–2017)	12	0.011	0.029	0.020	8
12–19 years
1 (2007–2009)	10	0.010	0.023	0.015	2
3 (2012–2013)	12	<LOD	0.054	NC-L	NC-L
4 (2014–2015)	12	0.0074	0.032	NC-M	NC-M
5 (2016–2017)	12	0.012	0.023	0.018	7
20–39 years
1 (2007–2009)	13	<LOD	0.039	0.020	31
3 (2012–2013)	12	<LOD	0.067	NC-L	NC-L
4 (2014–2015)	13	0.016	0.033	0.024	14
5 (2016–2017)	13	0.014	0.035	0.023	16
40–59 years
1 (2007–2009)	14	0.025	0.051	0.037	3
3 (2012–2013)	12	<LOD	0.058	0.028	35
4 (2014–2015)	12	0.029	0.069	0.047	7
5 (2016–2017)	12	0.021	0.042	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	0.063	0.033	53
3 (2012–2013)	12	0.040	0.066	0.046	5
4 (2014–2015)	12	0.029	0.059	NC-M	NC-M
5 (2016–2017)	12	0.034	0.046	0.041	3
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.21.
Table 7.1.22 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.22 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.23
1,2,3,4,7,8-Hexachlorodibenzofuran (HxCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	6.1	3.6	8
4 (2014–2015)	67	<LOD	8.4	NC-M	NC-M
5 (2016–2017)	67	<LOD	6.7	3.5	7
Total, 6–79 years
1 (2007–2009)	59	<LOD	16	NC-L	NC-L
3 (2012–2013)	59	<LOD	6.1	3.6	6
4 (2014–2015)	61	<LOD	7.9	NC-M	NC-M
5 (2016–2017)	61	<LOD	6.7	3.5	7
Females, 6–79 years
1 (2007–2009)	30	<LOD	9.1	NC-L	NC-L
3 (2012–2013)	29	<LOD	6.1	3.4	12
4 (2014–2015)	31	<LOD	7.6	NC-M	NC-M
5 (2016–2017)	31	1.6	4.8	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	16	NC-L	NC-L
3 (2012–2013)	30	<LOD	5.4	3.8	1
4 (2014–2015)	30	2.3	7.9	NC-M	NC-M
5 (2016–2017)	30	<LOD	6.7	3.9	9
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	4.6	2.5	58
4 (2014–2015)	6	1.4	8.4	2.9	33
5 (2016–2017)	6	2.8	5.1	3.9	13
6–11 years
1 (2007–2009)	10	<LOD	9.1	NC-L	NC-L
3 (2012–2013)	11	<LOD	4.6	2.0	26
4 (2014–2015)	12	<LOD	7.4	NC-M	NC-M
5 (2016–2017)	12	2.1	6.7	3.9	9
12–19 years
1 (2007–2009)	10	<LOD	1.9	NC-L	NC-L
3 (2012–2013)	12	<LOD	5.4	NC-M	NC-M
4 (2014–2015)	12	2.8	5.0	NC-M	NC-M
5 (2016–2017)	12	<LOD	6.3	3.7	1
20–39 years
1 (2007–2009)	13	<LOD	16	NC-L	NC-L
3 (2012–2013)	12	1.6	6.1	4.0	23
4 (2014–2015)	13	2.2	5.5	3.6	35
5 (2016–2017)	13	2.9	6.5	3.5	1
40–59 years
1 (2007–2009)	14	<LOD	3.7	NC-L	NC-L
3 (2012–2013)	12	1.7	4.5	3.6	1
4 (2014–2015)	12	2.7	7.9	5.4	19
5 (2016–2017)	12	1.6	4.4	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	4.0	NC-L	NC-L
3 (2012–2013)	12	3.1	5.1	3.7	5
4 (2014–2015)	12	3.8	7.6	NC-M	NC-M
5 (2016–2017)	12	3.0	5.1	3.8	9
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.0, 0.45, 0.22 and 0.29 pg/g lipid, respectively.
Table 7.1.23 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.23 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.24
1,2,3,4,7,8-Hexachlorodibenzofuran (HxCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.031	0.019	7
4 (2014–2015)	67	<LOD	0.045	NC-M	NC-M
5 (2016–2017)	67	<LOD	0.038	0.017	11
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.094	NC-L	NC-L
3 (2012–2013)	59	<LOD	0.031	0.019	5
4 (2014–2015)	61	<LOD	0.045	NC-M	NC-M
5 (2016–2017)	61	<LOD	0.038	0.017	12
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.051	NC-L	NC-L
3 (2012–2013)	29	<LOD	0.031	0.018	10
4 (2014–2015)	31	<LOD	0.045	NC-M	NC-M
5 (2016–2017)	31	0.0086	0.023	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.094	NC-L	NC-L
3 (2012–2013)	30	<LOD	0.026	0.021	1
4 (2014–2015)	30	0.011	0.036	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.038	0.019	16
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.022	0.011	64
4 (2014–2015)	6	0.0070	0.036	0.014	32
5 (2016–2017)	6	0.012	0.020	0.017	18
6–11 years
1 (2007–2009)	10	<LOD	0.047	NC-L	NC-L
3 (2012–2013)	11	<LOD	0.020	0.0092	21
4 (2014–2015)	12	<LOD	0.033	NC-M	NC-M
5 (2016–2017)	12	0.0097	0.025	0.014	7
12–19 years
1 (2007–2009)	10	<LOD	0.010	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.022	NC-M	NC-M
4 (2014–2015)	12	0.012	0.025	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.025	0.014	6
20–39 years
1 (2007–2009)	13	<LOD	0.094	NC-L	NC-L
3 (2012–2013)	12	0.0090	0.029	0.020	16
4 (2014–2015)	13	0.012	0.024	0.018	19
5 (2016–2017)	13	0.014	0.038	0.017	8
40–59 years
1 (2007–2009)	14	<LOD	0.025	NC-L	NC-L
3 (2012–2013)	12	0.010	0.026	0.021	2
4 (2014–2015)	12	0.017	0.038	0.030	1
5 (2016–2017)	12	0.0086	0.026	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	0.027	NC-L	NC-L
3 (2012–2013)	12	0.016	0.031	0.021	4
4 (2014–2015)	12	0.017	0.045	NC-M	NC-M
5 (2016–2017)	12	0.016	0.028	0.020	13
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.23.
Table 7.1.24 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.24 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.25
1,2,3,6,7,8-Hexachlorodibenzofuran (HxCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	7.7	3.7	5
4 (2014–2015)	67	<LOD	9.2	NC-M	NC-M
5 (2016–2017)	67	<LOD	5.8	3.5	10
Total, 6–79 years
1 (2007–2009)	59	<LOD	6.2	3.5	9
3 (2012–2013)	59	<LOD	7.7	3.7	6
4 (2014–2015)	61	<LOD	9.2	NC-M	NC-M
5 (2016–2017)	61	<LOD	5.8	3.5	10
>Females, 6–79 years
1 (2007–2009)	30	<LOD	5.5	3.0	6
3 (2012–2013)	29	<LOD	7.7	3.9	4
4 (2014–2015)	31	<LOD	7.7	NC-M	NC-M
5 (2016–2017)	31	1.7	4.7	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	6.2	3.9	12
3 (2012–2013)	30	<LOD	6.8	3.6	17
4 (2014–2015)	30	2.0	9.2	NC-M	NC-M
5 (2016–2017)	30	<LOD	5.8	3.8	14
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	4.1	2.0	50
4 (2014–2015)	6	2.9	5.6	3.4	5
5 (2016–2017)	6	2.4	4.4	3.0	11
6–11 years
1 (2007–2009)	10	<LOD	4.2	2.0	18
3 (2012–2013)	11	1.3	6.2	2.8	21
4 (2014–2015)	12	<LOD	6.1	NC-M	NC-M
5 (2016–2017)	12	1.9	5.6	3.4	13
12–19 years
1 (2007–2009)	10	<LOD	4.6	2.4	14
3 (2012–2013)	12	<LOD	6.6	NC-M	NC-M
4 (2014–2015)	12	2.5	4.4	NC-M	NC-M
5 (2016–2017)	12	<LOD	5.8	3.6	7
20–39 years
1 (2007–2009)	13	0.12	6.0	3.3	6
3 (2012–2013)	12	<LOD	7.7	3.4	8
4 (2014–2015)	13	1.9	5.6	3.3	36
5 (2016–2017)	13	2.6	5.4	3.7	3
40–59 years
1 (2007–2009)	14	2.7	6.2	4.1	5
3 (2012–2013)	12	2.3	5.7	4.2	11
4 (2014–2015)	12	3.4	9.2	5.7	29
5 (2016–2017)	12	1.7	4.6	NC-M	NC-M
60–79 years
1 (2007–2009)	12	1.1	6.1	3.7	36
3 (2012–2013)	12	3.4	6.8	4.7	11
4 (2014–2015)	12	4.0	7.7	NC-M	NC-M
5 (2016–2017)	12	2.4	5.2	3.8	18
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.1, 0.40, 0.19, and 0.34 pg/g lipid, respectively.
Table 7.1.25 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.25 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.26
1,2,3,6,7,8-Hexachlorodibenzofuran (HxCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.040	0.020	7
4 (2014–2015)	67	<LOD	0.045	NC-M	NC-M
5 (2016–2017)	67	<LOD	0.029	0.017	14
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.043	0.022	9
3 (2012–2013)	59	<LOD	0.040	0.020	8
4 (2014–2015)	61	<LOD	0.045	NC-M	NC-M
5 (2016–2017)	61	<LOD	0.029	0.017	14
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.038	0.019	7
3 (2012–2013)	29	<LOD	0.040	0.021	1
4 (2014–2015)	31	<LOD	0.045	NC-M	NC-M
5 (2016–2017)	31	0.0086	0.026	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.043	0.025	11
3 (2012–2013)	30	<LOD	0.036	0.020	18
4 (2014–2015)	30	0.011	0.042	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.029	0.019	21
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.016	0.0094	57
4 (2014–2015)	6	0.015	0.024	0.017	4
5 (2016–2017)	6	0.0096	0.018	0.013	15
6–11 years
1 (2007–2009)	10	<LOD	0.022	0.010	18
3 (2012–2013)	11	0.0062	0.025	0.013	17
4 (2014–2015)	12	<LOD	0.027	NC-M	NC-M
5 (2016–2017)	12	0.0080	0.022	0.012	13
12–19 years
1 (2007–2009)	10	<LOD	0.023	0.012	14
3 (2012–2013)	12	<LOD	0.024	NC-M	NC-M
4 (2014–2015)	12	0.010	0.022	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.023	0.014	13
20–39 years
1 (2007–2009)	13	0.00071	0.035	0.020	5
3 (2012–2013)	12	<LOD	0.040	0.018	15
4 (2014–2015)	13	0.012	0.024	0.016	20
5 (2016–2017)	13	0.011	0.027	0.017	9
40–59 years
1 (2007–2009)	14	0.018	0.043	0.028	4
3 (2012–2013)	12	0.012	0.034	0.025	11
4 (2014–2015)	12	0.018	0.042	0.031	11
5 (2016–2017)	12	0.0092	0.029	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.0084	0.041	0.026	36
3 (2012–2013)	12	0.020	0.037	0.026	10
4 (2014–2015)	12	0.018	0.045	NC-M	NC-M
5 (2016–2017)	12	0.012	0.028	0.021	21
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.25.
Table 7.1.26 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.26 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.27
1,2,3,7,8,9-Hexachlorodibenzofuran (HxCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	3.3	NC-L	NC-L
4 (2014–2015)	67	<LOD	8.6	NC-M	NC-M
5 (2016–2017)	67	<LOD	3.6	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	59	<LOD	3.3	NC-L	NC-L
4 (2014–2015)	61	<LOD	8.6	NC-M	NC-M
5 (2016–2017)	61	<LOD	3.6	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	29	<LOD	1.5	NC-L	NC-L
4 (2014–2015)	31	<LOD	4.1	NC-M	NC-M
5 (2016–2017)	31	<LOD	2.8	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	30	<LOD	3.3	NC-L	NC-L
4 (2014–2015)	30	<LOD	8.6	NC-M	NC-M
5 (2016–2017)	30	<LOD	3.6	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	1.8	NC-L	NC-L
5 (2016–2017)	6	<LOD	1.2	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	11	<LOD	1.5	NC-L	NC-L
4 (2014–2015)	12	<LOD	3.7	NC-M	NC-M
5 (2016–2017)	12	<LOD	1.6	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	3.4	NC-L	NC-L
5 (2016–2017)	12	<LOD	2.8	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	4.1	1.8	50
5 (2016–2017)	13	<LOD	3.6	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	3.3	NC-L	NC-L
4 (2014–2015)	12	<LOD	8.6	2.4	61
5 (2016–2017)	12	<LOD	1.1	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	1.9	NC-L	NC-L
4 (2014–2015)	12	<LOD	2.1	NC-M	NC-M
5 (2016–2017)	12	<LOD	1.6	1.1	3
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.4, 0.57, 0.37 and 0.44 pg/g lipid, respectively.
Table 7.1.27 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.27 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.28
1,2,3,7,8,9-Hexachlorodibenzofuran (HxCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.018	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.040	NC-M	NC-M
5 (2016–2017)	67	<LOD	0.021	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	59	<LOD	0.018	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.040	NC-M	NC-M
5 (2016–2017)	61	<LOD	0.021	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	29	<LOD	0.0096	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.018	NC-M	NC-M
5 (2016–2017)	31	<LOD	0.011	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	30	<LOD	0.018	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.040	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.021	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	0.0090	NC-L	NC-L
5 (2016–2017)	6	<LOD	0.0050	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	11	<LOD	0.0066	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.014	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.0070	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.013	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.011	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.018	0.0088	36
5 (2016–2017)	13	<LOD	0.021	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.018	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.040	0.012	48
5 (2016–2017)	12	<LOD	0.0057	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.0096	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.011	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.0081	0.0057	7
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.27.
Table 7.1.28 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.28 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.29
2,3,4,6,7,8-Hexchlorodibenzofuran (HxCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	4.4	NC-L	NC-L
4 (2014–2015)	67	<LOD	6.1	NC-M	NC-M
5 (2016–2017)	67	<LOD	5.1	1.8	8
Total, 6–79 years
1 (2007–2009)	59	<LOD	2.8	1.4	13
3 (2012–2013)	59	<LOD	4.4	NC-L	NC-L
4 (2014–2015)	61	<LOD	6.1	NC-M	NC-M
5 (2016–2017)	61	<LOD	5.1	1.8	7
Females, 6–79 years
1 (2007–2009)	30	<LOD	2.8	1.3	18
3 (2012–2013)	29	<LOD	3.0	NC-L	NC-L
4 (2014–2015)	31	<LOD	4.4	NC-M	NC-M
5 (2016–2017)	31	<LOD	3.8	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	2.2	1.4	9
3 (2012–2013)	30	<LOD	4.4	NC-L	NC-L
4 (2014–2015)	30	<LOD	6.1	NC-M	NC-M
5 (2016–2017)	30	<LOD	5.1	2.1	13
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	3.4	1.3	69
4 (2014–2015)	6	<LOD	2.3	NC-L	NC-L
5 (2016–2017)	6	<LOD	3.5	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	2.2	1.2	39
3 (2012–2013)	11	<LOD	1.7	NC-L	NC-L
4 (2014–2015)	12	<LOD	5.7	NC-L	NC-L
5 (2016–2017)	12	<LOD	5.1	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	1.5	1.0	22
3 (2012–2013)	12	<LOD	3.5	NC-L	NC-L
4 (2014–2015)	12	<LOD	2.7	NC-M	NC-M
5 (2016–2017)	12	<LOD	3.8	1.8	25
20–39 years
1 (2007–2009)	13	0.15	2.8	1.5	37
3 (2012–2013)	12	<LOD	4.4	NC-L	NC-L
4 (2014–2015)	13	1.2	3.9	2.2	37
5 (2016–2017)	13	1.1	4.1	1.9	13
40–59 years
1 (2007–2009)	14	<LOD	1.9	1.4	9
3 (2012–2013)	12	<LOD	3.0	1.6	4
4 (2014–2015)	12	1.5	6.1	3.4	33
5 (2016–2017)	12	<LOD	2.3	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.62	2.1	1.3	16
3 (2012–2013)	12	<LOD	3.8	1.7	14
4 (2014–2015)	12	<LOD	3.3	NC-M	NC-M
5 (2016–2017)	12	1.5	2.6	2.0	3
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.4, 0.41, 0.25 and 0.34 pg/g lipid, respectively.
Table 7.1.29 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.29 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.30
2,3,4,6,7,8-Hexchlorodibenzofuran (HxCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.023	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.028	NC-M	NC-M
5 (2016–2017)	67	<LOD	0.024	0.0088	12
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.015	0.0085	11
3 (2012–2013)	59	<LOD	0.023	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.028	NC-M	NC-M
5 (2016–2017)	61	<LOD	0.024	0.0089	11
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.015	0.0081	16
3 (2012–2013)	29	<LOD	0.014	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.021	NC-M	NC-M
5 (2016–2017)	31	<LOD	0.014	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.013	0.0088	6
3 (2012–2013)	30	<LOD	0.023	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.028	NC-M	NC-M
5 (2016–2017)	30	<LOD	0.024	0.010	18
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.016	0.0061	74
4 (2014–2015)	6	<LOD	0.012	NC-L	NC-L
5 (2016–2017)	6	<LOD	0.014	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	0.011	0.0061	39
3 (2012–2013)	11	<LOD	0.0075	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.026	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.019	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.0072	0.0052	22
3 (2012–2013)	12	<LOD	0.014	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.013	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.014	0.0068	19
20–39 years
1 (2007–2009)	13	0.00089	0.015	0.0086	34
3 (2012–2013)	12	<LOD	0.023	NC-L	NC-L
4 (2014–2015)	13	0.0070	0.017	0.011	22
5 (2016–2017)	13	0.0053	0.024	0.0090	20
40–59 years
1 (2007–2009)	14	<LOD	0.013	0.0097	9
3 (2012–2013)	12	<LOD	0.018	0.0096	2
4 (2014–2015)	12	0.0088	0.028	0.018	16
5 (2016–2017)	12	<LOD	0.014	NC-M	NC-M
60–79 years
1 (2007–2009)	12	0.0042	0.015	0.0091	16
3 (2012–2013)	12	<LOD	0.020	0.0096	12
4 (2014–2015)	12	<LOD	0.017	NC-M	NC-M
5 (2016–2017)	12	0.0083	0.014	0.011	8
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.29.
Table 7.1.30 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.30 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.31
1,2,3,4,6,7,8-Heptachlorodibenzofuran (HpCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	16	6.5	2
4 (2014–2015)	67	<LOD	14	NC-M	NC-M
5 (2016–2017)	67	3.2	15	5.5	2
Total, 6–79 years
1 (2007–2009)	59	<LOD	21	NC-L	NC-L
3 (2012–2013)	59	<LOD	16	6.4	3
4 (2014–2015)	61	<LOD	14	NC-M	NC-M
5 (2016–2017)	61	3.2	15	5.4	2
Females, 6–79 years
1 (2007–2009)	30	<LOD	20	NC-L	NC-L
3 (2012–2013)	29	<LOD	12	6.2	4
4 (2014–2015)	31	<LOD	10	6.0	16
5 (2016–2017)	31	3.2	8.4	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	21	NC-L	NC-L
3 (2012–2013)	30	3.8	16	6.7	8
4 (2014–2015)	30	4.2	14	NC-M	NC-M
5 (2016–2017)	30	3.9	15	6.3	3
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	6.0	10	8.7	9
4 (2014–2015)	6	4.2	9.5	6.6	9
5 (2016–2017)	6	5.0	8.9	6.8	5
6–11 years
1 (2007–2009)	10	<LOD	20	NC-L	NC-L
3 (2012–2013)	11	3.3	9.3	6.1	5
4 (2014–2015)	12	<LOD	14	NC-M	NC-M
5 (2016–2017)	12	4.6	15	8.5	14
12–19 years
1 (2007–2009)	10	<LOD	11	NC-L	NC-L
3 (2012–2013)	12	4.4	16	NC-M	NC-M
4 (2014–2015)	12	4.1	11	NC-M	NC-M
5 (2016–2017)	12	3.6	9.5	6.8	3
20–39 years
1 (2007–2009)	13	<LOD	21	NC-L	NC-L
3 (2012–2013)	12	<LOD	9.3	6.7	19
4 (2014–2015)	13	3.8	9.2	5.4	21
5 (2016–2017)	13	4.4	7.8	5.7	1
40–59 years
1 (2007–2009)	14	<LOD	5.5	NC-L	NC-L
3 (2012–2013)	12	4.4	7.6	6.4	10
4 (2014–2015)	12	3.5	11	6.7	28
5 (2016–2017)	12	3.2	5.8	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	6.9	NC-L	NC-L
3 (2012–2013)	12	3.2	7.0	4.9	10
4 (2014–2015)	12	3.8	10	NC-M	NC-M
5 (2016–2017)	12	3.3	7.0	4.9	0
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 1.8, 0.42, 0.24 and 0.32 pg/g lipid, respectively.
Table 7.1.31 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.31 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.32
1,2,3,4,6,7,8-Heptachlorodibenzofuran (HpCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.058	0.034	1
4 (2014–2015)	67	<LOD	0.063	NC-M	NC-M
5 (2016–2017)	67	0.015	0.046	0.026	6
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.12	NC-L	NC-L
3 (2012–2013)	59	<LOD	0.058	0.034	1
4 (2014–2015)	61	<LOD	0.063	NC-M	NC-M
5 (2016–2017)	61	0.015	0.046	0.026	6
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.10	NC-L	NC-L
3 (2012–2013)	29	<LOD	0.058	0.032	5
4 (2014–2015)	31	<LOD	0.059	0.031	7
5 (2016–2017)	31	0.015	0.030	NC-M	NC-M
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.12	NC-L	NC-L
3 (2012–2013)	30	0.021	0.058	0.035	8
4 (2014–2015)	30	0.022	0.063	NC-M	NC-M
5 (2016–2017)	30	0.020	0.046	0.030	8
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.024	0.042	0.038	1
4 (2014–2015)	6	0.019	0.041	0.033	11
5 (2016–2017)	6	0.021	0.032	0.029	1
6–11 years
1 (2007–2009)	10	<LOD	0.10	NC-L	NC-L
3 (2012–2013)	11	0.016	0.045	0.028	10
4 (2014–2015)	12	<LOD	0.063	NC-M	NC-M
5 (2016–2017)	12	0.020	0.039	0.029	8
12–19 years
1 (2007–2009)	10	<LOD	0.055	NC-L	NC-L
3 (2012–2013)	12	0.018	0.058	NC-M	NC-M
4 (2014–2015)	12	0.018	0.054	NC-M	NC-M
5 (2016–2017)	12	0.015	0.038	0.026	3
20–39 years
1 (2007–2009)	13	<LOD	0.12	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.045	0.035	12
4 (2014–2015)	13	0.021	0.034	0.027	5
5 (2016–2017)	13	0.022	0.046	0.027	5
40–59 years
1 (2007–2009)	14	<LOD	0.038	NC-L	NC-L
3 (2012–2013)	12	0.023	0.044	0.037	9
4 (2014–2015)	12	0.022	0.051	0.036	10
5 (2016–2017)	12	0.017	0.033	NC-M	NC-M
60–79 years
1 (2007–2009)	12	<LOD	0.048	NC-L	NC-L
3 (2012–2013)	12	0.019	0.036	0.027	10
4 (2014–2015)	12	0.018	0.059	NC-M	NC-M
5 (2016–2017)	12	0.017	0.038	0.026	4
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.31.
Table 7.1.32 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.32 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.33
1,2,3,4,7,8,9-Heptachlorodibenzofuran (HpCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	67	<LOD	13	NC-L	NC-L
5 (2016–2017)	67	<LOD	0.75	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	5.4	NC-L	NC-L
3 (2012–2013)	59	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	61	<LOD	13	NC-L	NC-L
5 (2016–2017)	61	<LOD	0.75	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	4.0	NC-L	NC-L
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	4.9	NC-L	NC-L
5 (2016–2017)	31	<LOD	0.69	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	5.4	NC-L	NC-L
3 (2012–2013)	30	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	30	<LOD	13	NC-L	NC-L
5 (2016–2017)	30	<LOD	<LOD	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	5.4	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.4	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	4.0	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	13	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	4.8	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	4.9	NC-L	NC-L
5 (2016–2017)	13	<LOD	<LOD	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	4.6	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.1	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	1.8	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.6	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.69	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LODs for cycles 1, 3, 4 and 5 are 2.6, 0.60, 0.39 and 0.53 pg/g lipid, respectively.
Table 7.1.33 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.33 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.34
1,2,3,4,7,8,9-Heptachlorodibenzofuran (HpCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.064	NC-L	NC-L
5 (2016–2017)	67	<LOD	0.0041	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.030	NC-L	NC-L
3 (2012–2013)	59	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.064	NC-L	NC-L
5 (2016–2017)	61	<LOD	0.0041	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.021	NC-L	NC-L
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.022	NC-L	NC-L
5 (2016–2017)	31	<LOD	0.0041	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.030	NC-L	NC-L
3 (2012–2013)	30	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.064	NC-L	NC-L
5 (2016–2017)	30	<LOD	<LOD	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	0.028	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0070	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.020	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.064	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.028	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.022	NC-L	NC-L
5 (2016–2017)	13	<LOD	<LOD	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.030	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0058	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	0.012	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0085	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0041	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.33.
Table 7.1.34 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.34 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.35
1,2,3,4,6,7,8,9-Octachlorodibenzofuran (OCDF) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	67	<LOD	32	NC-L	NC-L
5 (2016–2017)	67	<LOD	34	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	59	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	61	<LOD	32	NC-L	NC-L
5 (2016–2017)	61	<LOD	34	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	32	NC-L	NC-L
5 (2016–2017)	31	<LOD	<LOD	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	30	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	30	<LOD	6.0	NC-L	NC-L
5 (2016–2017)	30	<LOD	34	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	2.5	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	5.9	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	32	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	3.2	NC-L	NC-L
5 (2016–2017)	13	<LOD	<LOD	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.5	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	2.1	NC-M	NC-M
5 (2016–2017)	12	<LOD	34	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are 2.2, 3.4, 0.40 and 0.95 (0.17–3.7) pg/g lipid, respectively.
Table 7.1.35 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.35 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 7.1.36
1,2,3,4,6,7,8,9-Octachlorodibenzofuran (OCDF) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (pg/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.13	NC-L	NC-L
5 (2016–2017)	67	<LOD	0.17	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	59	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.13	NC-L	NC-L
5 (2016–2017)	61	<LOD	0.17	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.13	NC-L	NC-L
5 (2016–2017)	31	<LOD	<LOD	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	30	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.029	NC-L	NC-L
5 (2016–2017)	30	<LOD	0.17	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	0.013	NC-L	NC-L
5 (2016–2017)	6	<LOD	<LOD	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.027	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.13	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.014	NC-L	NC-L
5 (2016–2017)	13	<LOD	<LOD	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0071	NC-L	NC-L
5 (2016–2017)	12	<LOD	<LOD	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	<LOD	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.012	NC-M	NC-M
5 (2016–2017)	12	<LOD	0.17	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD; NC-M: Data not calculated as pools representing over 10% of the target population were missing due to sample loss
Note: The mean LODs for cycles 1, 3, 4 and 5 are presented in Table 7.1.35.
Table 7.1.36 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 7.1.36 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

References

Aylward, L.L., LaKind, J.S., Hays, S.M. (2008). Derivation of biomonitoring equivalent (BE) values for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds: a screening tool for interpretation of biomonitoring data in a risk assessment context. Journal of Toxicology and Environmental Health, Part A, 71(22), 1499–1508.

Alberta Health and Wellness (2008). Chemicals in Serum of Pregnant Women in Alberta. Alberta Biomonitoring Program, Public Health Division, Edmonton, AB. Retrieved December 27, 2019.

ATSDR (Agency for Toxic Substance and Disease Registry) (1994). Toxicological Profile for Chlorodibenzofurans (CDFs). U.S. Department of Health and Human Services, Atlanta, GA. Retrieved December 2, 2019.

ATSDR (Agency for Toxic Substance and Disease Registry) (1998). Toxicological Profile for Chlorinated Dibenzo-p-dioxins (CDDs). U.S. Department of Health and Human Services, Atlanta, GA. Retrieved December 2, 2019.

Canada (1999). Canadian Environmental Protection Act, 1999. SC 1999, c. 33. Retrieved May 29, 2019.

Caron, É.B., Dumas, P., Lemire, M., Ayotte, P. (2019). MercuNorth final report: Persistent pollutants concentrations in plasma of participants from Sweden, Norway, Iceland, Finland, and Nunavik. Centre de recherche du CHU de Québec–Université Laval, Centre de toxicologie du Québec, INSPQ. [unpublished]

Consonni, D., Sindaco, R., Bertazzi, P.A. (2012). Blood levels of dioxins, furans, dioxin-like PCBs, and TEQs in general populations: a review, 1989–2010. Environment International, 44, 151–162.

Environment Canada and Health Canada (1990). Priority substances List Assessment Report No. 1: Polychlorinated Dibenzodioxins and Polychlorinated Dibenzofurans. Minister of Supply and Services Canada, Ottawa, ON. Retrieved December 4, 2019.

Environment Canada (2013a). Toxic substances list: dibenzofuran. Minister of Environment, Ottawa, ON. Retrieved January 8, 2020.

Environment Canada (2013b). Toxic substances list: Dibenzo-para-dioxin. Minister of Environment, Ottawa, ON. Retrieved January 8, 2020.

EPA (U.S. Environmental Protection Agency) (2019). Learn about Dioxin. U.S. Environmental Protection Agency, Washington, DC. Retrieved December 2, 2019.

Health Canada (2006). Dioxins and Furans. Minister of Health, Ottawa, ON. Retrieved December 2, 2019.

Health Canada (2016). Concentration of Contaminants and Other Chemicals in Food Composites. Minister of Health, Ottawa, ON. Retrieved May 29, 2019.

Health Canada (2019). List of Ingredients that are Prohibited for Use in Cosmetic Products (Hotlist). Minister of Health, Ottawa, ON. Retrieved January 8, 2020.

International Agency for Research on Cancer (2012). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans — Volume 100F: Chemical Agents and Related Occupations. World Health Organization, Lyon. Retrieved December 3, 2019.

Lampa, E., Eguchi, A., Todaka, E., Mori, C. (2018). Fetal exposure markers of dioxins and dioxin-like PCBs. Environmental Science and Pollution Research, 25(12), 11940–11947.

Marinković, N., Pašalić, D., Ferenčak, G., Gršković, B., Rukavina, A. (2010). Dioxins and human toxicity. Archives of Industrial Hygiene and Toxicology, 61(4), 445–453.

Patterson, D.G., Needham, L.L., Pirkle, J.L., Roberts, D.W., Bagby, J., Garrett, W.A., Andrews, J.S. Jr., Falk, H., Bernert, J.T., Sampson, E.J., et al. (1988). Correlation between serum and adipose tissue levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin in 50 persons from Missouri. Archives of Environmental Contamination and Toxicology, 17(2), 139–143.

Paustenbach, D.J., Wenning, R.J., Lau, V., Harrington, N.W., Rennix, D.K., Parsons, A.H. (1992). Recent developments on the hazards posed by 2,3,7,8-tetrachlorodibenzo-p-dioxin in soil: Implications for setting risk-based cleanup levels at residential and industrial sites. Journal of Toxicology and Environmental Health, 36(2), 103–150.

Rawn, D.K.F., Ryan, J.J., Sadler, A.R., Sun, W.F., Haines, D., Macey, K., Van Oostdam, J. (2012). PCDD/F and PCB concentrations in sera from the Canadian Health Measures Survey (CHMS) from 2007 to 2009. Environment International, 47, 48–55.

Saskatchewan Ministry of Health (2019). Northern Saskatchewan Prenatal Biomonitoring Study Technical Report. Saskatchewan Ministry of Health, Regina, SK. Retrieved January 8, 2020.

UNEP (United Nations Environment Programme) (2008). All POPs listed in the Stockholm Convention. Secretariat of the Stockholm Convention, Geneva. Retrieved May 29, 2019.

WHO (World Health Organization) (2010). Exposure to Dioxins and Dioxin-Like Substances: A Major Public Health Concern. WHO, Geneva. Retrieved January 8, 2020.

WHO (World Health Organization) (2016). Dioxins and their effects on human health. WHO, Geneva. Retrieved March 12, 2020.

8 Summaries and results for flame retardants

8.1 Hexabromocyclododecane

Hexabromocyclododecane (HBCD) is a brominated flame retardant that is used to slow the ignition and spread of fire. Technical HBCD is typically composed of three isomers designated alpha (α), beta (β) and gamma (γ). HBCD is produced synthetically. Technical products typically contain 10%–13% α-HBCD, 1%–12% β–HBCD and 75%–89% γ-HBCD (Environment Canada and Health Canada, 2011a; Heeb et al., 2005). The HBCD isomers measured in the Canadian Health Measures Survey (CHMS) are listed in Table 8.1.1.

Table 8.1.1
Hexabromocyclododecane isomers measured in pooled serum in the Canadian Health Measures Survey cycles 1 (2007–2009), 3 (2012–2013), 4 (2014–2015) and 5 (2016–2017)
Compound name	CASRN
alpha-Hexabromocyclododecane (α-HBCD)	134237-50-6
beta-Hexabromocyclododecane (β-HBCD)	134237-51-7
gamma-Hexabromocyclododecane (γ-HBCD)	134237-52-8

Currently in Canada, the only known intentional use of HBCD is in products used in the automotive sector (Environment and Climate Change Canada, 2018a). However, HBCD may also be present in manufactured items, such as foam packaging made from recycled polystyrene and toys made from recycled plastics (Abdallah et al., 2018; DiGangi et al., 2017). Historically, HBCD use was primarily in polystyrene foam insulation in building and construction materials (Environment and Climate Change Canada, 2018a). To a lesser extent, it was also used as a flame retardant in textiles for upholstered furniture, transportation seating, wall coverings and draperies, as well as in adhesives, paints and electronics.

HBCD does not occur naturally, but may enter the environment throughout its life cycle, from manufacturing through product use and disposal. In product applications, HBCD is mixed or dissolved rather than chemically bonded. As such, releases may occur in both indoor and outdoor environments. Due to its low vapour pressure and low water solubility, releases are expected to preferentially concentrate in household dust, soil and sediments rather than in air or water. HBCD has been detected in a wide array of environmental media, including air, water, soil and biota (Environment Canada and Health Canada, 2011b). Once in the environment, HBCD is persistent and bioaccumulative, with half-lives of 2, 60 and 240 days in air, water and sediment respectively (Environment Canada and Health Canada, 2011b; Schecter et al., 2012). Under some circumstances, such as adsorption to airborne particles, HBCD may be capable of undergoing long-range transport in the atmosphere (Environment Canada and Health Canada, 2011b). HBCD has been detected in air, sediments, water and biota in remote places far from areas of use (NCP, 2013). Monitoring of ambient air and biota in Canada’s Arctic indicates that HBCD levels have generally increased since the 1990s (NCP, 2013; Rigét et al., 2019).

The primary sources of exposure in the general population are food (including breast milk) and household dust (Environment Canada and Health Canada, 2011b). HBCD exposure may also occur through air, water and certain consumer products; however, exposure from these sources is low. While technical HBCD is predominantly composed of the γ-isomer, the α-isomer is commonly the primary isomer measured in environmental media, household dust and food (Abdallah et al., 2008; Fromme et al., 2014; Rigét et al., 2019; Schecter et al., 2012). This shift to the α-isomer may be due to a combination of factors, including solubility, partitioning behaviour and uptake (Covaci et al., 2006).

HBCD is expected to be readily absorbed following oral exposure (European Commission, 2008). Once absorbed, it can undergo stereoisomerization, hydroxylation and debromination in the liver. Studies in humans have demonstrated transplacental transfer of HBCD to developing fetuses. Studies in laboratory animals indicate that γ-HBCD and β-HBCD are more rapidly and extensively metabolized than α-HBCD (Erratico et al., 2016; Szabo et al., 2010; Szabo et al., 2011). α-HBCD has a greater potential to bioaccumulate due to its increased lipophilicity; biological samples generally contain α-HBCD as the predominant isomer (Rawn, Gaertner et al., 2014; Rawn, Ryan et al., 2014; Szabo et al., 2010; Szabo et al., 2011). HBCD isomers can be measured in human breast milk, adipose tissue and blood (EPA, 2010). Based upon studies in laboratory animals, elimination of HBCD is expected to occur mainly through feces and to a lesser degree through urine (Environment Canada and Health Canada, 2011b). In humans, a half-life of 165 days has been estimated for α-HBCD, while a half-life of 55 days has been estimated for the β- and γ-isomers (Abdallah and Harrad, 2011). Since α-HBCD has a longer biological half-life than the other isomers, serum α-HBCD levels may indicate long-term exposure.

Exposure to HBCD may result in adverse developmental and reproductive health effects, including altered behaviour and decreased fertility (Environment Canada and Health Canada, 2011b; European Commission, 2008; Health Canada, 2019). In addition, HBCD is a suspected endocrine disruptor, with effects observed on the thyroid hormone axis (Gannon, Moreau et al., 2019; Gannon, Nunnikhoven et al., 2019). There is no conclusive evidence for mutagenic or genotoxic effects (European Commission, 2008); consequently, HBCD is not classified as a carcinogen by the International Agency for Research on Cancer (2020) or other agencies.

HBCD is listed on Schedule 1, List of Toxic Substances, under the Canadian Environmental Protection Act, 1999 (CEPA 1999) and is classified as a persistent organic pollutant by the Stockholm Convention on Persistent Organic Pollutants (Canada, 1999; Environment and Climate Change Canada, 2018b; UNEP, 2008). The Government of Canada considers it to be persistent, bioaccumulative, toxic and primarily the result of human activity. As such, HBCD is targeted for virtual elimination from the environment (Track 1 substance) (Environment Canada and Health Canada, 2011a). Risk management actions under CEPA 1999 have been developed to prohibit the import, manufacture, use, sale and offer for sale of HBCD and products containing it, with a limited number of exceptions (Canada, 2012). Environment and Climate Change Canada (2018a) has proposed regulatory amendments to remove the exemptions on HBCD. Internationally, Canada is working with the United Nations to eliminate the import, export, production and use of HBCD through the Convention on Long-Range Transboundary Air Pollution and the Stockholm Convention on Persistent Organic Pollutants.

Prior to the release of the CHMS data set, only limited data existed for HBCD blood levels in Canadians. In northern Canada, HBCD was measured in pooled serum from pregnant women (Ryan et al., 2005). This study included 10 pools of maternal serum from 560 individuals from Nunavut and the Northwest Territories sampled from 1994–1999. β- and γ-HBCD were not detected; α-HBCD was detected in three of the 10 pools, with concentrations of 0.5, 0.7 and 0.9 ng/g lipid.

Three HBCD isomers (α, β and γ) were analyzed in pooled serum samples of CHMS participants aged 6–79 in cycle 1 (2007–2009) and aged 3–79 in cycle 3 (2012–2013), cycle 4 (2014–2015) and cycle 5 (2016–2017). Data from these cycles are presented as ng/g lipid and ng/g serum. Finding a measurable amount of HBCD isomers in serum is an indicator of exposure to HBCD. It does not necessarily mean that an adverse health effect will occur.

Rawn, Ryan et al. (2014) published HBCD data from pooled serum samples collected in cycle 1 of the CHMS. These previously published results were generated using a different statistical approach. As a result, they are not directly comparable with the data presented in this report.

Table 8.1.2
alpha-Hexabromocyclododecane (α-HBCD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV ^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	4.1	0.83	13
4 (2014–2015)	67	<LOD	5.9	1.0	3
5 (2016–2017)	67	<LOD	7.1	1.6	5
Total, 6–79 years
1 (2007–2009)	59	0.13	6.3	0.61	28
3 (2012–2013)	59	<LOD	4.1	0.82	14
4 (2014–2015)	61	<LOD	5.9	1.0	3
5 (2016–2017)	61	<LOD	7.1	1.5	2
Females, 6–79 years
1 (2007–2009)	30	0.13	3.4	0.58	35
3 (2012–2013)	29	<LOD	4.1	0.53	14
4 (2014–2015)	31	<LOD	2.8	0.98	18
5 (2016–2017)	31	<LOD	7.1	1.5	3
Males, 6–79 years
1 (2007–2009)	29	0.17	6.3	0.64	21
3 (2012–2013)	30	<LOD	4.0	1.1	13
4 (2014–2015)	30	<LOD	5.9	1.1	11
5 (2016–2017)	30	<LOD	5.8	1.6	2
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.48	1.8	0.97	6
4 (2014–2015)	6	0.60	2.4	0.90	18
5 (2016–2017)	6	<LOD	6.7	4.8	27
6–11 years
1 (2007–2009)	10	0.17	6.3	0.86	46
3 (2012–2013)	11	<LOD	1.5	0.74	8
4 (2014–2015)	12	<LOD	2.6	0.74	34
5 (2016–2017)	12	<LOD	6.0	1.9	42
12–19 years
1 (2007–2009)	10	0.13	1.6	0.62	38
3 (2012–2013)	12	<LOD	1.7	0.80	38
4 (2014–2015)	12	<LOD	2.8	0.95	42
5 (2016–2017)	12	<LOD	4.1	1.6	52
20–39 years
1 (2007–2009)	13	0.16	1.0	0.42	14
3 (2012–2013)	12	<LOD	4.1	0.53	24
4 (2014–2015)	13	<LOD	3.7	0.99	9
5 (2016–2017)	13	0.41	5.8	1.8	22
40–59 years
1 (2007–2009)	14	0.24	0.91	0.53	22
3 (2012–2013)	12	<LOD	1.6	0.65	23
4 (2014–2015)	12	<LOD	3.6	NC-L	NC-L
5 (2016–2017)	12	<LOD	7.1	1.3	15
60–79 years
1 (2007–2009)	12	0.28	3.4	1.0	52
3 (2012–2013)	12	<LOD	4.0	1.7	12
4 (2014–2015)	12	<LOD	5.9	1.5	1
5 (2016–2017)	12	0.55	4.8	1.4	1
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 is 0.18 ng/g lipid and the method LOD for cycles 3, 4 and 5 is 0.37 ng/g lipid.
Table 8.1.2 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.2 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.1.3
alpha-Hexabromocyclododecane (α-HBCD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.021	0.0043	14
4 (2014–2015)	67	<LOD	0.025	0.0053	15
5 (2016–2017)	67	<LOD	0.038	0.0080	5
Total, 6–79 years
1 (2007–2009)	59	0.00066	0.033	0.0039	30
3 (2012–2013)	59	<LOD	0.021	0.0043	14
4 (2014–2015)	61	<LOD	0.025	0.0053	15
5 (2016–2017)	61	<LOD	0.038	0.0076	2
Females, 6–79 years
1 (2007–2009)	30	0.00066	0.026	0.0039	39
3 (2012–2013)	29	<LOD	0.020	0.0028	14
4 (2014–2015)	31	<LOD	0.015	0.0052	28
5 (2016–2017)	31	<LOD	0.038	0.0074	3
Males, 6–79 years
1 (2007–2009)	29	0.00088	0.033	0.0039	21
3 (2012–2013)	30	<LOD	0.021	0.0059	14
4 (2014–2015)	30	<LOD	0.025	0.0054	3
5 (2016–2017)	30	<LOD	0.034	0.0077	2
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.0023	0.0082	0.0043	2
4 (2014–2015)	6	0.0029	0.011	0.0043	19
5 (2016–2017)	6	<LOD	0.032	0.021	33
6–11 years
1 (2007–2009)	10	0.00088	0.033	0.0045	46
3 (2012–2013)	11	<LOD	0.0067	0.0034	14
4 (2014–2015)	12	<LOD	0.012	0.0032	30
5 (2016–2017)	12	<LOD	0.022	0.0066	37
12–19 years
1 (2007–2009)	10	0.00066	0.0077	0.0031	37
3 (2012–2013)	12	<LOD	0.0068	0.0033	38
4 (2014–2015)	12	<LOD	0.014	0.0043	48
5 (2016–2017)	12	<LOD	0.016	0.0064	57
20–39 years
1 (2007–2009)	13	0.0010	0.0062	0.0025	11
3 (2012–2013)	12	<LOD	0.020	0.0027	17
4 (2014–2015)	13	<LOD	0.021	0.0052	23
5 (2016–2017)	13	0.0020	0.034	0.0086	17
40–59 years
1 (2007–2009)	14	0.0017	0.0060	0.0036	22
3 (2012–2013)	12	<LOD	0.010	0.0038	23
4 (2014–2015)	12	<LOD	0.024	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.038	0.0073	15
60–79 years
1 (2007–2009)	12	0.0019	0.026	0.0074	54
3 (2012–2013)	12	<LOD	0.021	0.0089	12
4 (2014–2015)	12	<LOD	0.025	0.0075	14
5 (2016–2017)	12	0.0029	0.024	0.0073	6
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 and the method LOD for cycles 3, 4 and 5 are presented in Table 8.1.2.
Table 8.1.3 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.3 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.1.4
beta-Hexabromocyclododecane (β-HBCD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	1.0	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.94	NC-L	NC-L
5 (2016–2017)	67	<LOD	11	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	1.1	NC-L	NC-L
3 (2012–2013)	59	<LOD	1.0	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.94	NC-L	NC-L
5 (2016–2017)	61	<LOD	11	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.25	NC-L	NC-L
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.78	NC-L	NC-L
5 (2016–2017)	31	<LOD	0.50	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	1.1	NC-L	NC-L
3 (2012–2013)	30	<LOD	1.0	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.94	NC-L	NC-L
5 (2016–2017)	30	<LOD	11	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	6	<LOD	0.43	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	1.1	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.43	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.58	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.44	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.29	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.25	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.78	NC-L	NC-L
5 (2016–2017)	13	<LOD	4.8	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.23	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.94	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.42	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	0.20	NC-L	NC-L
3 (2012–2013)	12	<LOD	1.0	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.42	NC-L	NC-L
5 (2016–2017)	12	<LOD	11	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 is 0.31 ng/g lipid and the method LOD for cycles 3, 4 and 5 is 0.24 ng/g lipid.
Table 8.1.4 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.4 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.1.5
beta-Hexabromocyclododecane (β-HBCD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.0052	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.0043	NC-L	NC-L
5 (2016–2017)	67	<LOD	0.055	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.0057	NC-L	NC-L
3 (2012–2013)	59	<LOD	0.0052	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.0043	NC-L	NC-L
5 (2016–2017)	61	<LOD	0.055	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.0015	NC-L	NC-L
3 (2012–2013)	29	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.0035	NC-L	NC-L
5 (2016–2017)	31	<LOD	0.0023	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.0057	NC-L	NC-L
3 (2012–2013)	30	<LOD	0.0052	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.0043	NC-L	NC-L
5 (2016–2017)	30	<LOD	0.055	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	6	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	6	<LOD	0.0017	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	0.0057	NC-L	NC-L
3 (2012–2013)	11	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	<LOD	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0016	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.0029	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0018	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0010	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.0015	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.0035	NC-L	NC-L
5 (2016–2017)	13	<LOD	0.028	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.0015	NC-L	NC-L
3 (2012–2013)	12	<LOD	<LOD	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0043	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0022	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	0.0013	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.0052	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0020	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.055	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 and the method LOD for cycles 3, 4 and 5 are presented in Table 8.1.4.
Table 8.1.5 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.5 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.1.6
gamma-Hexabromocyclododecane (γ-HBCD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	8.5	NC-L	NC-L
4 (2014–2015)	67	<LOD	2.9	NC-L	NC-L
5 (2016–2017)	67	<LOD	43	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	1.6	NC-L	NC-L
3 (2012–2013)	59	<LOD	8.5	NC-L	NC-L
4 (2014–2015)	61	<LOD	2.9	NC-L	NC-L
5 (2016–2017)	61	<LOD	43	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.22	NC-L	NC-L
3 (2012–2013)	29	<LOD	1.6	NC-L	NC-L
4 (2014–2015)	31	<LOD	2.5	NC-L	NC-L
5 (2016–2017)	31	<LOD	2.4	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	1.6	NC-L	NC-L
3 (2012–2013)	30	<LOD	8.5	NC-L	NC-L
4 (2014–2015)	30	<LOD	2.9	NC-L	NC-L
5 (2016–2017)	30	<LOD	43	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.84	NC-L	NC-L
4 (2014–2015)	6	<LOD	0.43	NC-L	NC-L
5 (2016–2017)	6	0.48	2.0	1.5	32
6–11 years
1 (2007–2009)	10	<LOD	1.5	0.22	39
3 (2012–2013)	11	<LOD	0.61	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.1	NC-L	NC-L
5 (2016–2017)	12	<LOD	2.9	1.3	62
12–19 years
1 (2007–2009)	10	<LOD	1.6	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.60	NC-L	NC-L
4 (2014–2015)	12	<LOD	1.0	NC-L	NC-L
5 (2016–2017)	12	<LOD	1.3	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.21	NC-L	NC-L
3 (2012–2013)	12	<LOD	1.6	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.97	NC-L	NC-L
5 (2016–2017)	13	<LOD	43	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.090	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.60	0.40	12
4 (2014–2015)	12	<LOD	2.9	NC-L	NC-L
5 (2016–2017)	12	<LOD	1.4	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	0.11	NC-L	NC-L
3 (2012–2013)	12	<LOD	8.5	NC-L	NC-L
4 (2014–2015)	12	<LOD	2.5	0.95	20
5 (2016–2017)	12	<LOD	4.0	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 is 0.16 ng/g lipid and the method LOD for cycles 3, 4 and 5 is 0.38 ng/g lipid.
Table 8.1.6 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.6 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.1.7
gamma-Hexabromocyclododecane (γ-HBCD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	<LOD	0.044	NC-L	NC-L
4 (2014–2015)	67	<LOD	0.015	NC-L	NC-L
5 (2016–2017)	67	<LOD	0.25	NC-L	NC-L
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.0080	NC-L	NC-L
3 (2012–2013)	59	<LOD	0.044	NC-L	NC-L
4 (2014–2015)	61	<LOD	0.015	NC-L	NC-L
5 (2016–2017)	61	<LOD	0.25	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.0011	NC-L	NC-L
3 (2012–2013)	29	<LOD	0.0077	NC-L	NC-L
4 (2014–2015)	31	<LOD	0.013	NC-L	NC-L
5 (2016–2017)	31	<LOD	0.015	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.0080	NC-L	NC-L
3 (2012–2013)	30	<LOD	0.044	NC-L	NC-L
4 (2014–2015)	30	<LOD	0.015	NC-L	NC-L
5 (2016–2017)	30	<LOD	0.25	NC-L	NC-L
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	<LOD	0.0034	NC-L	NC-L
4 (2014–2015)	6	<LOD	0.0021	NC-L	NC-L
5 (2016–2017)	6	0.0020	0.0096	0.0065	37
6–11 years
1 (2007–2009)	10	<LOD	0.0078	0.0011	39
3 (2012–2013)	11	<LOD	0.0024	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0048	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0084	0.0043	59
12–19 years
1 (2007–2009)	10	<LOD	0.0080	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.0022	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.0054	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0055	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.0012	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.0077	NC-L	NC-L
4 (2014–2015)	13	<LOD	0.0063	NC-L	NC-L
5 (2016–2017)	13	<LOD	0.25	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.00063	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.0034	0.0023	13
4 (2014–2015)	12	<LOD	0.015	NC-L	NC-L
5 (2016–2017)	12	<LOD	0.0083	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	0.00076	NC-L	NC-L
3 (2012–2013)	12	<LOD	0.044	NC-L	NC-L
4 (2014–2015)	12	<LOD	0.013	0.0051	29
5 (2016–2017)	12	<LOD	0.020	NC-L	NC-L
LOD: limit of detection; NA: Data not available as participants under the age of six years were not included in cycle 1; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 and the method LOD for cycles 3, 4 and 5 are presented in Table 8.1.6.
Table 8.1.7 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.7 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.1.8
Total hexabromocyclododecane (sum of α-HBCD, β-HBCD, γ-HBCD) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g lipid) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	0.50	14	1.6	29
4 (2014–2015)	67	0.50	6.6	1.7	1
5 (2016–2017)	67	0.50	54	3.0	8
Total, 6–79 years
1 (2007–2009)	59	0.28	8.9	0.92	24
3 (2012–2013)	59	0.50	14	1.6	31
4 (2014–2015)	61	0.50	6.6	1.7	1
5 (2016–2017)	61	0.50	54	2.9	12
Females, 6–79 years
1 (2007–2009)	30	0.28	3.7	0.83	25
3 (2012–2013)	29	0.50	4.4	1.1	15
4 (2014–2015)	31	0.50	5.4	1.6	6
5 (2016–2017)	31	0.50	8.3	2.2	3
Males, 6–79 years
1 (2007–2009)	29	0.42	8.9	1.0	22
3 (2012–2013)	30	0.50	14	2.1	39
4 (2014–2015)	30	0.50	6.6	1.8	8
5 (2016–2017)	30	0.50	54	3.5	15
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.79	2.8	1.5	18
4 (2014–2015)	6	0.91	2.7	1.2	9
5 (2016–2017)	6	1.1	9.0	6.6	26
6–11 years
1 (2007–2009)	10	0.46	8.9	1.3	41
3 (2012–2013)	11	0.50	2.0	1.1	9
4 (2014–2015)	12	0.50	2.9	1.1	14
5 (2016–2017)	12	0.50	7.4	3.3	48
12–19 years
1 (2007–2009)	10	0.40	3.4	1.2	44
3 (2012–2013)	12	0.50	2.0	1.2	19
4 (2014–2015)	12	0.50	3.5	1.5	35
5 (2016–2017)	12	0.50	5.4	2.4	52
20–39 years
1 (2007–2009)	13	0.28	1.1	0.71	10
3 (2012–2013)	12	0.50	4.4	1.0	17
4 (2014–2015)	13	0.50	4.0	1.5	10
5 (2016–2017)	13	0.72	54	4.0	33
40–59 years
1 (2007–2009)	14	0.42	1.1	0.75	15
3 (2012–2013)	12	0.50	2.2	1.2	17
4 (2014–2015)	12	0.50	6.6	1.6	32
5 (2016–2017)	12	0.50	8.3	2.0	18
60–79 years
1 (2007–2009)	12	0.50	3.7	1.3	45
3 (2012–2013)	12	0.50	14	3.7	51
4 (2014–2015)	12	0.77	6.2	2.6	6
5 (2016–2017)	12	1.1	20	2.6	31
NA: Data not available as participants under the age of six years were not included in cycle 1
Note: For each pool within a cycle, the sum of α-HBCD, β-HBCD, γ-HBCD is calculated. If the value of an isomer is less than the limit of detection (LOD) or missing due to sample loss, then the imputed value is used. If all isomers are reported as less than the LOD and/or missing, then the sum will be the sum of the imputed values.
Table 8.1.8 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.8 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.1.9
Total hexabromocyclododecane (sum of α-HBCD, β-HBCD, γ-HBCD) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g serum) for the general population from the Canadian Health Measures Survey (2007–2017)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 3–79 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	65	0.0022	0.073	0.0084	29
4 (2014–2015)	67	0.0019	0.033	0.0088	11
5 (2016–2017)	67	0.0016	0.32	0.015	10
Total, 6–79 years
1 (2007–2009)	59	0.0017	0.046	0.0057	25
3 (2012–2013)	59	0.0022	0.073	0.0085	31
4 (2014–2015)	61	0.0019	0.033	0.0089	11
5 (2016–2017)	61	0.0016	0.32	0.015	13
Females, 6–79 years
1 (2007–2009)	30	0.0017	0.028	0.0055	29
3 (2012–2013)	29	0.0025	0.021	0.0060	14
4 (2014–2015)	31	0.0019	0.029	0.0084	15
5 (2016–2017)	31	0.0016	0.045	0.011	2
Males, 6–79 years
1 (2007–2009)	29	0.0021	0.046	0.0060	21
3 (2012–2013)	30	0.0022	0.073	0.011	39
4 (2014–2015)	30	0.0032	0.033	0.0095	8
5 (2016–2017)	30	0.0020	0.32	0.018	18
3–5 years
1 (2007–2009)	NA	NA	NA	NA	NA
3 (2012–2013)	6	0.0038	0.011	0.0065	10
4 (2014–2015)	6	0.0045	0.012	0.0060	10
5 (2016–2017)	6	0.0046	0.043	0.029	32
6–11 years
1 (2007–2009)	10	0.0024	0.046	0.0069	41
3 (2012–2013)	11	0.0022	0.010	0.0051	15
4 (2014–2015)	12	0.0023	0.014	0.0050	11
5 (2016–2017)	12	0.0018	0.027	0.011	44
12–19 years
1 (2007–2009)	10	0.0020	0.017	0.0062	44
3 (2012–2013)	12	0.0024	0.0080	0.0050	18
4 (2014–2015)	12	0.0022	0.018	0.0068	41
5 (2016–2017)	12	0.0016	0.022	0.0094	57
20–39 years
1 (2007–2009)	13	0.0017	0.0068	0.0042	8
3 (2012–2013)	12	0.0025	0.021	0.0053	10
4 (2014–2015)	13	0.0019	0.023	0.0082	26
5 (2016–2017)	13	0.0035	0.32	0.021	40
40–59 years
1 (2007–2009)	14	0.0029	0.0074	0.0051	16
3 (2012–2013)	12	0.0028	0.013	0.0068	18
4 (2014–2015)	12	0.0022	0.033	0.0084	16
5 (2016–2017)	12	0.0028	0.045	0.011	19
60–79 years
1 (2007–2009)	12	0.0034	0.028	0.0090	47
3 (2012–2013)	12	0.0030	0.073	0.020	50
4 (2014–2015)	12	0.0041	0.029	0.013	18
5 (2016–2017)	12	0.0058	0.10	0.014	27
NA: Data not available as participants under the age of six years were not included in cycle 1
Note: For each pool within a cycle, the sum of α-HBCD, β-HBCD, γ-HBCD is calculated. If the value of an isomer is less than the limit of detection (LOD) or missing due to sample loss, then the imputed value is used. If all isomers are reported as less than the LOD and/or missing, then the sum will be the sum of the imputed values.
Table 8.1.9 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.1.9 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

References

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Abdallah, M.A.E., Harrad, S. (2011). Tetrabromobisphenol-A, hexabromocyclododecane and its degradation products in UK human milk: Relationship to external exposure. Environment International, 37(2), 443–448.

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UNEP (United Nations Environment Programme) (2008). All POPs listed in the Stockholm Convention. Secretariat of the Stockholm Convention, Geneva. Retrieved May 29, 2019.

8.2 Polybrominated diphenyl ethers

Polybrominated diphenyl ethers (PBDEs) are a class of structurally similar brominated hydrocarbons where 1–10 bromine atoms are attached to the benzene rings of the diphenyl ether. There are 209 possible molecular combinations, or congeners, varying in the number of bromine atoms and their locations on the two rings. The PBDE congeners are named based on their structure, but are more commonly referred to by their International Union of Pure and Applied Chemistry (IUPAC) number. This approach systematically assigns numbers to the different congeners, with higher numbers assigned to those with a larger number of bromine atoms. Congeners are commonly classified into 10 groups designated as mono (one bromine atom) through deca (10 bromine atoms) (ATSDR, 2017). Table 8.2.1 lists the 23 PBDE congeners measured in pooled serum in the Canadian Health Measures Survey (CHMS).

Table 8.2.1
Polybrominated diphenyl ethers (PBDEs) measured in pooled serum in the Canadian Health Measures Survey
IUPAC no.	Compound name	CASRN	Cycle 1 (2007–2009)	Cycle 3 (2012-2013)	Cycle 4 (2014-2015)	Cycle 5 (2016-2017)
PBDE 15	4,4'-Dibromodiphenyl ether	2050-47-7	Yes	No	No	No
PBDE 17	2,2',4-Tribromodiphenyl ether	147217-75-2	Yes	No	No	No
PBDE 28	2,4,4'-Tribromodiphenyl ether	41318-75-6	Yes	No	No	No
PBDE 37	3,4,4'-Tribromodiphenyl ether	1472217-81-0	Yes	No	No	No
PBDE 47	2,2',4,4'-Tetrabromodiphenyl ether	5436-43-1	Yes	Yes	Yes	Yes
PBDE 66	2,3',4,4'-Tetrabromodiphenyl ether	189084-61-5	Yes	No	No	No
PBDE 71	2,3',4',6-Tetrabromodiphenyl ether	189084-62-6	Yes	No	No	No
PBDE 75	2,4,4′,6-Tetrabromodiphenyl ether	189084-63-7	Yes	No	No	No
PBDE 77	3,3′,4,4′-Tetrabromodiphenyl ether	93703-48-1	Yes	No	No	No
PBDE 85	2,2’,3,4,4’-Pentabromodiphenyl ether	182346-21-0	Yes	No	No	No
PBDE 99	2,2',4,4',5-Pentabromodiphenyl ether	60348-60-9	Yes	Yes	Yes	Yes
PBDE 100	2,2',4,4'6-Pentabromodiphenyl ether	189084-64-8	Yes	Yes	Yes	Yes
PBDE 119	2,3′,4,4′,6-Pentabromodiphenyl ether	189084-66-0	Yes	No	No	No
PBDE 126	3,3′,4,4′,5-Pentabromodiphenyl ether	366791-32-4	Yes	No	No	No
PBDE 138	2,2′,3,4,4′,5′-Hexabromodiphenyl ether	182677-30-1	Yes	No	No	No
PBDE 153	2,2',4,4',5,5'-Hexabromodiphenyl ether	68631-49-2	Yes	Yes	Yes	Yes
PBDE 154	2,2’,4,4’,5,6’-Hexabromodiphenyl ether	207122-15-4	Yes	No	No	No
PBDE 160	2,3,3',4,5,6-Hexabromodiphenyl ether	NA	Yes	No	No	No
PBDE 181	2,2′,3,4,4′,5,6-Heptabromodiphenyl ether	189084-67-1	Yes	No	No	No
PBDE 183	2,2’,3,4,4’,5’,6-Heptabromodiphenyl ether	207122-16-5	Yes	No	No	No
PBDE 190	2,3,3',4,4',5,6-Heptabromodiphenyl ether	189084-68-2	Yes	No	No	No
PBDE 205	2,3,3′,4,4′,5,5′,6-Octabromodiphenyl ether	446255-56-7	Yes	No	No	No
PBDE 209	2,2',3,3',4,4',5,5',6,6'-Decabromodiphenyl ether	1163-19-5	Yes	Yes	Yes	Yes

PBDEs are produced synthetically as mixtures (containing varying combinations of PBDEs) and are used as flame retardants. Production of three commercial PBDE products (pentaBDE, octaBDE and decaBDE) began in the late 1970s (ATSDR, 2017). Each commercial product is a mixture of various congeners. Commercial pentaBDE is predominantly composed of tetraBDE, pentaBDE and hexaBDE congeners; commercial octaBDE is mainly composed of hexaBDE, heptaBDE and octaBDE; and commercial decaBDE is almost completely composed of decaBDE. The commercial products differ in composition, use, manufactured volume, toxicology and environmental distribution. In product applications, PBDEs are physically mixed rather than chemically bonded (ATSDR, 2017). These products were never manufactured in Canada. However, they have been imported as part of chemical formulations — such as resins, polymers or substrates that contain PBDEs — and in semi-finished or finished articles, such as computer housings, household appliances, furniture and automotive/aircraft seating and interiors, as well as in a variety of electrical and electronic components (Environment and Climate Change Canada, 2016). The use of commercial pentaBDE and octaBDE mixtures has been phased out globally since 2006 and prohibited in Canada since 2008 (Environment Canada, 2010b; Health Canada, 2019). Export to Canada of the commercial decaBDE mixture manufactured in the United States ended in mid-2012, and there are currently no known Canadian users or importers (Health Canada, 2019). However, commercial decaBDE is still used in certain manufactured items imported into Canada, such as automotive parts and pallets (Environment and Climate Change Canada, 2018). In addition, PBDEs may be present in manufactured items made from recycled plastics containing PBDEs, including pens, shredders, staplers and wire spools (Environment and Climate Change Canada, 2018).

PBDEs do not generally occur naturally in the environment. However, other types of brominated diphenyl ethers (e.g. methoxylated PBDEs) have been found to occur naturally in marine environments (Teuten et al., 2005). Entry into the environment may occur throughout their life cycles — from handling and manufacturing through to product use and disposal. PBDEs in existing stock of in-use products continue to be a source of PBDEs in the environment. PBDEs have been detected in a wide array of environmental media, including air, water, soil and biota (ATSDR, 2017; EPA, 2010). Once in the environment, PBDEs are persistent, and most congeners are considered bioaccumulative (ATSDR, 2017). Half-lives vary by congener, with estimates ranging from less than a day in water to up to 50 years in sediment (ATSDR, 2017). Certain PBDEs also have the ability to undergo long-range transport in the atmosphere (Environment Canada, 2010b). They have been detected in air, sediments, water and biota in remote places far from areas of use (NCP, 2013). Monitoring of ambient air and biota in Canada’s Arctic indicates that levels of PBDEs generally increased from the 1990s until the early 2000s, but are now declining (NCP, 2013).

The predominant routes of exposure to PBDEs in the general Canadian population are the ingestion of food (including breast milk) and the inhalation and ingestion of house dust (Health Canada, 2006; Health Canada, 2012). Other minor routes of exposure include inhalation from the off-gassing of furniture and electrical and electronic appliances into indoor air as well as dermal exposure through contact with PBDE-containing products, such as textiles and polymers (Health Canada, 2006; Health Canada, 2012). The specific PBDE congeners in food and house dust vary. Globally, PBDEs 47, 99 and 209 are the highest contributors to PBDE levels in food (Boucher et al., 2018). Dietary studies have demonstrated that fish and other aquatic foods generally have the highest levels of PBDEs, followed by meat and meat products (Boucher et al., 2018; Fromme et al., 2016). Studies conducted on house dust in Canada reported that among the PBDEs tested, the most abundant congeners were PBDEs 47, 99, 100, 153 and 209 (Abbasi et al., 2016; Shoeib et al., 2012; Wilford et al., 2005). In children aged six months to four years, evidence suggests that mouthing of hard plastic toys may be an important route of exposure, with PBDE 209 as the main contributor (Chen, et al., 2009; Ionas et al., 2014).

PBDEs are variably absorbed following oral exposure; lower-brominated congener groups, such as tetraBDE, pentaBDE and hexaBDE, are more likely than decaBDE to enter the body (ATSDR, 2017; EFSA, 2011). The extent of absorption following inhalation is unknown due to the paucity of evidence in humans and laboratory animals (ATSDR, 2017). Once absorbed, the higher brominated PBDEs undergo debromination to form lower-brominated congeners (ATSDR, 2017; Health Canada, 2012). The lower-brominated PBDEs are persistent and accumulate preferentially in adipose tissue. Studies in humans have demonstrated transplacental transfer of PBDEs to developing fetuses. PBDEs have been measured in human adipose tissue, serum and breast milk (ATSDR, 2017). Elimination of PBDEs from the body occurs mainly through the feces, with a very small amount eliminated in urine (ATSDR, 2017). Higher brominated congeners tend to have shorter half-lives than lower-brominated congeners; apparent half-lives for PBDE congeners in blood have been observed to range from 15 days for decaBDE to as high as 94 days for octaBDE congeners (ATSDR, 2017). The presence of a lower-brominated congener in the body may reflect environmental exposure, either to that congener or to a higher brominated PBDE that has undergone debromination. The predominant congeners identified in breast milk and other human tissues are PBDEs 47, 99, 100, 153 and 154 (McDonald, 2005).

Based on studies in laboratory animals and humans, the primary targets of PBDE toxicity appear to be the developing nervous and reproductive systems, the endocrine system, the liver and the male reproductive system (ATSDR, 2017). Epidemiological studies in humans have demonstrated correlations between PBDE exposures and various neurodevelopmental effects, including attention problems and impaired fine motor coordination (ATSDR, 2017). Data from humans and animals suggest that PBDEs, especially lower-brominated PBDEs, can interact with thyroid hormone homeostasis and male reproductive systems; animal studies have indicated the potential for hepatotoxicity (ATSDR, 2017). The International Agency for Research on Cancer (1990, 2019) has classified decaBDE as Group 3 (not classifiable as to their carcinogenicity to humans). The carcinogenicities of lower-brominated PBDE congeners have not been evaluated.

PBDEs — specifically tetraBDE, pentaBDE, hexaBDE, heptaBDE, octaBDE, nonaBDE and decaBDE congeners — are listed in Schedule 1, List of Toxic Substances, under Canadian Environmental Protection Act, 1999 (CEPA 1999) and are classified as persistent organic pollutants by the Stockholm Convention on Persistent Organic Pollutants (Canada, 1999; Environment and Climate Change Canada, 2016; UNEP, 2008). The Government of Canada considers these PBDE congeners to be persistent; however, only tetraBDE, pentaBDE and hexaBDEs are considered bioaccumulative (Canada, 2000; Environment Canada, 2006). As such, tetraBDE, pentaBDE and hexaBDEs are targeted for virtual elimination from the environment (Track 1 substances) (Environment Canada, 2010a). CEPA 1999 risk management actions have been developed to prohibit the manufacture, use, sale, offer for sale and import of PBDEs, with an exemption for manufactured items (Canada, 2012). Environment and Climate Change Canada (2018) has proposed regulatory amendments to remove the exemptions (except for decaBDE). PBDEs have also been analyzed as part of Health Canada's Total Diet Study surveys (Health Canada, 2016). Internationally, Canada is working with the United Nations to eliminate the import, export, production and use of PBDEs through the Convention on Long-Range Transboundary Air Pollution and the Stockholm Convention on Persistent Organic Pollutants.

PBDEs have been measured in pooled blood samples from pregnant women during regional biomonitoring studies conducted in Alberta, northern Saskatchewan and Nunavik. In 2005, the Alberta Biomonitoring Program conducted a biomonitoring study among pregnant women living in Alberta (Alberta Health and Wellness, 2008). Serum samples from 28,484 individuals were combined into 158 pools, and the highest concentrations were measured for PBDEs 47 and 99. Mean concentrations ranged from 11–340 ng/g lipid for PBDE 47 and from 2.5–470 ng/g lipid for PBDE 99. Another study, the Northern Saskatchewan Biomonitoring Study, was carried out from 2011–2013 in pregnant women living in northern Saskatchewan (Saskatchewan Ministry of Health, 2019). Serum samples from 841 individuals were combined into six pools. As with the other regional biomonitoring studies, PBDE 47 was the most highly detected, with concentrations ranging from 7.3–29 ng/g lipid. In 2013, a study of emerging Arctic contaminants was conducted in Nunavik under the Arctic Monitoring and Assessment Programme (AMAP) MercuNorth Project (Caron et al., 2019). Five pools of plasma samples from 78 pregnant women were analyzed for eight PBDEs (PBDEs 28, 47, 99, 100, 153, 154, 183 and 209). The highest concentration was measured for PBDE 47, with a geometric mean of 15.33 ng/g lipid.

PBDEs have also been measured in individual plasma samples as part of the CHMS and other Canadian biomonitoring studies. During cycle 1 (2007–2009) of the CHMS, the geometric mean PBDE 47 level in individual blood plasma samples from the Canadian population aged 20–79 was 10.04 ng/g lipid (Health Canada, 2010). Geometric means were not calculated for the remaining PBDEs (PBDEs 15, 17, 25, 28, 33, 99, 100 and 153) due to low detection levels. Higher plasma levels of PBDE 47 and PBDE 100 were associated with an increased prevalence of hypothyroidism in adult women aged 30–79 in cycle 1 of the CHMS (Oulhote et al., 2016). The population coverage of the CHMS excludes persons living on reserves and in other Indigenous settlements in Canadian provinces. However, this subpopulation has been surveyed as part of the First Nations Biomonitoring Initiative (FNBI), a nationally representative biomonitoring study of adult First Nations peoples living on reserves south of the 60th parallel (AFN, 2013). The study comprised 13 randomly selected First Nations communities in Canada with 471 First Nations participants aged 20 and older. In 2011, the geometric mean for PBDE 47 in blood plasma was 6.40 ng/g lipid. As with the CHMS, geometric means were not calculated for additional PBDEs included in the FNBI due to low detection levels.

The Maternal–Infant Research on Environmental Chemicals (MIREC) study is a national-level prospective cohort study that recruited 2,001 pregnant women aged 18 years and older from 10 cities across Canada from 2008–2011 (Arbuckle et al., 2013). There were 1,983 participants. Among them, 1,928 had available samples for PBDE analysis in their first trimester of pregnancy. The geometric mean concentration in maternal blood plasma was 7.02 ng/g lipid for PBDE 47; it was not calculated for the remaining PBDEs (PBDEs 28, 33, 99, 100 and 153) due to low detection levels (Fisher et al., 2016). In northern Canada, the contaminant component of the Inuit Health Survey (2007–2008) and the Nunavik Inuit Health Survey (2004) measured the body burden of PBDEs in 3,083 Inuit participants from communities in Nunavut, Nunavik, Nunatsiavut and the Inuvialuit Settlement Region (NCP, 2018). The geometric means for PBDEs 47, 99, 100, 153 and 209 in plasma for participants aged 18 years and older ranged from below the limit of detection to 28 ng/g lipid, with the highest concentrations measured for PBDEs 47 and 209.

Twenty-three PBDE congeners (Table 8.2.1) were analyzed in pooled serum samples of CHMS participants aged 6–79 in cycle 1.Five PBDE congeners — PBDEs 47, 99, 100, 153 and 209 — were analyzed in pooled serum samples of CHMS participants aged 3–79 in cycle 3 (2012–2013), cycle 4 (2014–2015) and cycle 5 (2016–2017). Data from these cycles are presented as ng/g lipid and ng/g serum. Finding a measurable amount of PBDE congeners in serum is an indicator of exposure to PBDEs. It does not necessarily mean that an adverse health effect will occur.

Rawn et al. (2014) published PBDE data from pooled serum samples collected in cycle 1 of the CHMS. These previously published results were generated using a different statistical approach. As a result, they are not directly comparable with the data presented in this report.

Table 8.2.2
4,4'-Dibromodiphenyl ether (PBDE 15) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g lipid) for the general population from the Canadian Health Measures Survey (2007–2009)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.66	0.22	15
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.66	0.21	34
Males, 6–79 years
1 (2007–2009)	29	0.12	0.45	0.23	2
6–11 years
1 (2007–2009)	10	<LOD	0.22	0.13	19
12–19 years
1 (2007–2009)	10	0.13	0.20	0.15	5
20–39 years
1 (2007–2009)	13	<LOD	0.37	0.18	33
40–59 years
1 (2007–2009)	14	0.12	0.66	0.29	10
60–79 years
1 (2007–2009)	12	<LOD	0.42	0.23	15
LOD: limit of detection
Note: The mean LOD for cycle 1 is 0.0096 ng/g lipid.
Table 8.2.2 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.2.2 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.2.3
4,4'-Dibromodiphenyl ether (PBDE 15) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g serum) for the general population from the Canadian Health Measures Survey (2007–2009)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.0045	0.0014	17
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.0045	0.0014	35
Males, 6–79 years
1 (2007–2009)	29	0.00065	0.0028	0.0014	0
6–11 years
1 (2007–2009)	10	<LOD	0.0011	0.00069	18
12–19 years
1 (2007–2009)	10	0.00065	0.0010	0.00075	5
20–39 years
1 (2007–2009)	13	<LOD	0.0023	0.0011	34
40–59 years
1 (2007–2009)	14	0.00083	0.0045	0.0019	12
60–79 years
1 (2007–2009)	12	<LOD	0.0028	0.0016	16
LOD: limit of detection
Note: The mean LOD for cycle 1 is presented in Table 8.2.2.
Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.2.4
2,2',4-Tribromodiphenyl ether (PBDE 17) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g lipid) for the general population from the Canadian Health Measures Survey (2007–2009)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.071	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.071	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.058	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	0.058	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.071	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.029	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.020	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	0.030	NC-L	NC-L
LOD: limit of detection; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 is 0.015 ng/g lipid.
Table 8.2.4 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.2.4 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.2.5
2,2',4-Tribromodiphenyl ether (PBDE 17) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g serum) for the general population from the Canadian Health Measures Survey (2007–2009)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 6–79 years
1 (2007–2009)	59	<LOD	0.00036	NC-L	NC-L
Females, 6–79 years
1 (2007–2009)	30	<LOD	0.00036	NC-L	NC-L
Males, 6–79 years
1 (2007–2009)	29	<LOD	0.00030	NC-L	NC-L
6–11 years
1 (2007–2009)	10	<LOD	0.00030	NC-L	NC-L
12–19 years
1 (2007–2009)	10	<LOD	0.00036	NC-L	NC-L
20–39 years
1 (2007–2009)	13	<LOD	0.00017	NC-L	NC-L
40–59 years
1 (2007–2009)	14	<LOD	0.00014	NC-L	NC-L
60–79 years
1 (2007–2009)	12	<LOD	0.00020	NC-L	NC-L
LOD: limit of detection; NC-L: Data not calculated as over 40% of pools were below the LOD
Note: The mean LOD for cycle 1 is presented in Table 8.2.4.
Table 8.2.5 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.2.5 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.2.6
2,4,4'-Tribromodiphenyl ether (PBDE 28) (lipid adjusted) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g lipid) for the general population from the Canadian Health Measures Survey (2007–2009)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 6–79 years
1 (2007–2009)	59	0.66	1.8	1.1	5
Females, 6–79 years
1 (2007–2009)	30	0.73	1.7	0.99	6
Males, 6–79 years
1 (2007–2009)	29	0.66	1.8	1.1	4
6–11 years
1 (2007–2009)	10	0.66	1.4	0.98	5
12–19 years
1 (2007–2009)	10	0.73	1.5	0.94	9
20–39 years
1 (2007–2009)	13	0.76	1.3	1.0	15
40–59 years
1 (2007–2009)	14	0.67	1.7	1.1	6
60–79 years
1 (2007–2009)	12	0.83	1.8	1.2	8
Note: The mean limit of detection for cycle 1 is 0.015 ng/g lipid.
Table 8.2.6 footnote a Each pool was composed of serum from 71 to 133 individuals Return to Table footnote a referrer Table 8.2.6 footnote b Coefficient of variation (CV): 0.0 ≤ CV < 16.6 acceptable; 16.6 ≤ CV ≤ 33.3 use with caution; CV > 33.3 use with a high degree of caution. See section 6.1.1 for more information on interpreting estimates based on their CV. Return to Table footnote b referrer

Table 8.2.7
2,4,4'-Tribromodiphenyl ether (PBDE 28) (whole weight) — Arithmetic mean, minimum and maximum pooled serum concentrations (ng/g serum) for the general population from the Canadian Health Measures Survey (2007–2009)
Cycle	Total Number of Pools^{Footnote a}	Minimum	Maximum	Arithmetic Mean	CV (%)^{Footnote b}
Total, 6–79 years
1 (2007–2009)	59	0.0036	0.012	0.0067	6
Females, 6–79 years
1 (2007–2009)	30	0.0038	0.012	0.0063	6
Males, 6–79 years
1 (2007–2009)	29	0.0036	0.012	0.0071	6
6–11 years
1 (2007–2009)	10	0.0036	0.0073	0.0052	4
12–19 years
1 (2007–2009)	10	0.0038	0.0081	0.0048	10
20–39 years
1 (2007–2009)	13	0.0042	0.0079	0.0060	17
40–59 years
1 (2007–2009)	14	0.0046	0.012	0.0075	5
60–79 years

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Report on Human Biomonitoring of Environmental Chemicals in Pooled Samples

Table of Contents

Acknowledgements

1 Introduction

References

2 Objectives

3 Pooling design and collection

3.1 Sample size and allocation

3.2 Blood collection

3.3 Pool formation and methodology

3.4 Variance estimation

3.5 Missing data

References

4 Laboratory analyses

4.1 Dioxins, furans and dioxin-like polychlorinated biphenyls

4.2 Flame retardants

4.2.1 Hexabromocyclododecane and tetrabromobisphenol A

4.2.2 Polybrominated diphenyl ethers

4.3 Organochlorine pesticides

4.4 Polychlorinated biphenyls

4.5 Lipids

References

5 Statistical data analyses

6 Considerations for interpreting the pooled serum biomonitoring data

6.1 Considerations for data analysis

6.1.1 Instability of variance estimates

6.1.2 Variation between cycles

6.1.3 Comparability with individual data

6.1.4 Lipid adjustment

References

7 Summaries and results for dioxins and furans

7.1 Dioxins and furans

References

8 Summaries and results for flame retardants

8.1 Hexabromocyclododecane

References

8.2 Polybrominated diphenyl ethers