New substances: risk assessment summary, new substances notification 19571, 19921, 19925, 19927, 20249 and 20350

Official title: New Substances Notifications 19571, 19921, 19925, 19927, 20249 and 20350: Amides, tall-oil fatty, N-[3-(dimethylamino)propyl] (Chemical Abstracts Service registry number 68650-79-3)

Regulatory decisions

Under the provisions for Substances and Activities New to Canada in Part 5 of the Canadian Environmental Protection Act, 1999 (CEPA), and pursuant to section 83 of the Act, the Minister of the Environment and the Minister of Health have assessed information in respect of the substance, and determined that the substance is anticipated to enter the environment in a quantity or concentration or under conditions that have or may have an immediate or long term harmful effect on the environment or its biological diversity, and constitute or may constitute a danger in Canada to human life or health.

In order to ensure that the substance does not cause harm to the Canadian environment or human health, its import and manufacture are authorized subject to conditions as described in:

• Ministerial Condition No. 19571 published in the Canada Gazette Part I, Vol. 152, No. 41 on October 13, 2018,
• Ministerial Condition No. 19921, Ministerial Condition No. 19925 and Ministerial Condition No. 19927 published in the Canada Gazette Part I, Vol. 153, No. 24 on June 15, 2019, 
• Ministerial Condition No. 20249 published in the Canada Gazette Part I, Vol. 154, No. 23 on June 6, 2020, and 
• Ministerial Condition No. 20350 published in the Canada Gazette Part I, Vol. 154, No. 27 on July 4, 2020.

Substance identity

The notified chemical is amides, tall-oil fatty, N-[3-(dimethylamino)propyl] (Chemical Abstracts Service registry number^{Footnote 1} 68650-79-3), and is considered a substance of unknown or variable composition, complex reaction products or biological materials (UVCB). 

Notified and potential uses

The substance is proposed to be imported into Canada in quantities greater than 10 000 kg/yr for the notified use in industrial pavement. Potential uses may include use in personal care products and household cleaners, textiles, paints and coatings and chemical manufacturing.

Environmental fate and behaviour

Based on its physical and chemical properties, if the substance is released to the environment, it will tend to partition to water, soil and sediment. The substance is not expected to be persistent in these compartments based on its moderate to high ready biodegradability (30-85 % over 28 days). The substance is not expected to bioaccumulate based on its low to moderate predicted bioaccumulation and bioconcentration factors (<1000 L/kg). 

Ecological assessment

Based on the available hazard information on the substance and surrogate data on structurally related chemicals, the substance is expected to have high acute toxicity in fish, aquatic invertebrates and algae (median lethal concentration and median effective concentration (EC₅₀) <1 mg/L), moderate chronic toxicity in fish (no-observed-effect-concentration (NOEC) 0.1-10 mg/L) and moderate to high chronic toxicity in aquatic invertebrates and algae (NOEC and 10% effective concentration (EC₁₀) <10 mg/L). The substance is expected to have low chronic toxicity in soil invertebrates (NOEC >10 mg/kg dry soil). Using the EC₁₀ from the most sensitive aquatic organism (algae) and by applying an assessment factor of 2 to account for species sensitivity variation, the chronic aquatic predicted no-effect concentration (PNEC) was calculated to be in the range of 1-10 µg/L. Using the EC₅₀ from the most sensitive aquatic organism (algae) and by applying an assessment factor of 2 to account for species sensitivity variation, the acute aquatic PNEC was calculated to be in the range of 1-10 µg/L. Using the NOEC from soil invertebrates and by applying an assessment factor of 20 to account for species sensitivity variation, the chronic benthic PNEC was calculated to be in the range of 1000-10 000 µg/L. These were used to estimate the ecological risk.

The notified and other potential activities in Canada were assessed to estimate the environmental exposure potential of the substance throughout its life cycle. Environmental exposure from the notified activities is expected to be mainly from cleaning of transportation vessels by release of the substance to water resulting in an acute predicted environmental concentration (PEC) in the range of 1-10 µg/L. For potential activities such as use and formulation of paints and coatings, environmental exposure is expected to be mainly from release of the substance to water resulting in a chronic PEC in the range of 0.1-1 µg/L and 1-10 µg/L, respectively. However, an increased environmental exposure potential may exist by release of the substance to water from potential activities resulting in a chronic PEC in the range of 10-100 µg/L for use in personal care products and household cleaners and chemical manufacturing, and in the range of 100-1000 µg/L for use in textiles. 

Comparing the aquatic PECs for the notified use and the potential uses including paints and coatings with the aquatic PNECs, the ratios are less than 1. This, along with other lines of evidence including environmental fate, hazard, and exposure, indicates that the substance is unlikely to cause ecological harm in Canada when used as notified or for the potential activities of use and formulation of paints and coatings.

However, based on the increased environmental exposure resulting from potential use in personal care products and household cleaners, textiles, or chemical manufacturing combined with the moderate to high aquatic toxicity, the substance is anticipated to cause ecological harm in Canada. 

Human health assessment

Based on the available hazard information for the substance and surrogate data on structurally related chemicals, the substance is expected to have a low acute toxicity by the oral and dermal routes (median lethal dose >2000 mg/kg body weight) and a moderate subchronic toxicity following repeat oral doses in mammalian test animals (28-day no-observed-adverse-effect level (NOAEL) 30-300 mg/kg-bw/day) and low dermal toxicity following repeat doses in mammalian test animals (90-day NOAEL >20 mg/kg-bw/day with no systemic toxicity observed at the highest dose tested). The substance is expected to have moderate reproductive/developmental toxicity following repeat oral doses in mammalian test animals (50-250 mg/kg-bw/day based on slightly decreased viability index at the high dose tested). The substance is expected to have low reproductive/developmental toxicity following repeat dermal doses in mammalian test animals (>100 mg/kg-bw/day with no evidence of developmental toxicity and no systemic toxicity observed at highest dose tested). It is expected to be a moderate skin sensitizer (29-64% response (guinea pig maximization test); 1-10% estimated concentration required to produce a stimulation index of 3 (EC3) (local lymph node assay)). It is not mutagenic in vitro and is not expected to be clastogenic in vitro. Therefore, the substance is unlikely to cause genetic damage. 

The oral provisional tolerable daily intake (PTDI) was calculated to be in the range of 100-1000 µg/kg-bw/day based on the NOAEL of the oral reproductive/developmental toxicity study in mammalian test animals. The dermal PTDI was calculated to be in the range of 1000-10 000 µg/kg-bw/day based on the NOAEL of the dermal subchronic toxicity study in mammalian test animals. The PTDI is the estimated level of long-term exposure without risk of adverse health effects. The acceptable exposure limit (AEL) for sensitization was calculated to be in the range of 1-10 µg/cm² based on the EC3 of the local lymph node assay in mammalian test animals. The AEL is the level of exposure below which no skin sensitization induction is expected in exposed individuals.

When the notified substance is used in industrial pavement, direct exposure of the general population is not expected due to the industrial nature of the use. Indirect exposure of the general population from environmental media such as drinking water is conservatively estimated to be at levels in the range of 0.1-1 µg/kg-bw/day for adults and 1-10 µg/kg-bw/day for toddlers. 

Potential uses of the substance include personal care products, where direct exposure of the general population is expected to be mainly by contact with the skin at levels in the range of 1000-10 000 µg/kg-bw/day and 0.01-100 µg/cm² for children and adults. Ingestion or contact with the eyes are also possible at levels in the range of 10-100 µg/kg-bw/day and 100-1000 µg/kg-bw/day, respectively, for adults. Potential uses of the substance include household detergents and cleaners, where direct exposure of the general population is expected to be mainly by contact with the skin at levels in the range of 10-100 µg/kg-bw/day and 0.1-1000 µg/cm². Potential uses of the substance include paints and coatings, where direct exposure of the general population would be expected to be mainly by contact with the skin at levels in the range of 1000-10 000 µg/kg-bw/day and 100-1000 µg/cm². Indirect exposure of the general population from environmental media such as drinking water associated with potential uses is conservatively estimated to be at levels in the range of 1-10 µg/kg-bw/day for children and adults.

Based on the low potential for exposure when used as notified, the substance is not likely to pose a significant health risk to the general population, and is therefore unlikely to be harmful to human health when used as notified.

However, based on the potential for increased dermal exposure if used in personal care products, household cleaners or consumer paints and coatings combined with the moderate reproductive/developmental toxicity and moderate skin sensitization, the substance is anticipated to be harmful to human health. 

Assessment conclusion

The substance is suspected to be harmful to the environment according to the criteria under paragraph 64(a) but not (b) of the Act and to human health according to the criteria under paragraph 64 (c). 

Due to the identified risk to human health related to moderate reproductive/developmental toxicity and moderate skin sensitization, and to the environment related to moderate to high aquatic toxicity, ministerial conditions were issued to restrict the manner in which the notifier may manufacture or import the substance with conditions on its use, handling, and disposal in order to mitigate these potential risks. These conditions are outlined in the following ministerial conditions:

• Ministerial Condition No. 19571, published in the Canada Gazette Part I, Vol. 152, No. 41 on October 13, 2018, 
• Ministerial Conditions No. 19921, 19925 and 19927, published in the Canada Gazette Part I, Vol. 153, No. 24 on June 15, 2019,
• Ministerial Condition No. 20249, published in the Canada Gazette Part I, Vol. 153, No. 24 on June 15, 2019, and
• Ministerial Condition No. 20350, published in the Canada Gazette Part I, Vol. 154, No. 27 on July 4, 2020.

A conclusion under CEPA, on this substance, is not relevant to, nor does it preclude an assessment against the hazard criteria for Workplace Hazardous Materials Information System that are specified in the Controlled Products Regulations or Hazardous Products Regulations for products intended for the workplace.