New substances: risk assessment summary, new substances notification 19283
Official title: New Substances Notification No. 19283: 2-Propenoic acid, 2-methyl-, (dialkylsubstituted) alkyl ester, polymer with butyl 2-propenoate and disubstituted propane mono-2-propenoate, 2,2'-(1,2-diazenediyl)bis[2-methylbutanenitrile]-initiated (Confidential Accession No. 19377-5)
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 have determined that it is not 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, constitute or may constitute a danger to the environment on which life depends, or constitute or may constitute a danger in Canada to human life or health.
Substance identity
The notified polymer is 2-propenoic acid, 2-methyl-, (dialkylsubstituted) alkyl ester, polymer with butyl 2-propenoate and disubstituted propane mono-2-propenoate, 2,2'-(1,2-diazenediyl)bis[2-methylbutanenitrile]-initiated (Confidential Accession No. 19377-5). The substance does not meet the Reduced Regulatory Requirements criteria according to the New Substances Notification Regulations (Chemicals and Polymers) because it contains potentially cationic amines.
Notified and potential activities
The substance is proposed to be manufactured in and/or imported into Canada in quantities greater than 10 000 kg/yr for the notified use in coatings. No other activities are anticipated in Canada.
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 soil and sediment. The substance is expected to be persistent in these compartments based on its complex chemical composition which will limit environmental degradation. The substance is not expected to bioaccumulate based on its high molecular weight and low octanol-water partition coefficient (log Kow 0-3) which will limit its ability to cross biological membranes.
Ecological assessment
Based on the available hazard information, the substance has low acute toxicity in fish (median lethal concentration >100 mg/L) and moderate chronic toxicity in algae (10% effective concentration (EC10) in the range of 0.1-10 mg/L). Using the EC10 from the most sensitive organism (algae) and by applying an assessment factor of 10 to account for species sensitivity variation, the predicted no-effect concentration (PNEC) was calculated to be in the range of 1000-10 000 µg/L, which was used to estimate the ecological risk.
The notified 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 and processing by release of the substance to water resulting in predicted environmental concentrations (PECs) in the range of 0.1-10 µg/L. No potential activities which could significantly increase environmental risks compared to those notified were identified.
Comparing the PEC with the PNEC, the ratio is 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.
Human health assessment
Based on the available hazard information, the substance has a low acute toxicity by the oral route (median lethal dose >2000 mg/kg body weight). The substance does not contain structural features associated with adverse human health effects.
When the notified substance is used in coatings, consumers may come into contact with end-use products containing the substance; however, direct exposure is not expected because the substance will be chemically reacted into a stable matrix once the product is cured and will be unavailable for uptake. Indirect exposure of the general population from environmental media is expected to be low given the specialized industrial use of the substance, which results in little or no release to the environment. No potential uses which could significantly increase human health risks compared to the notified uses were identified.
Based on the low potential for exposure and absence of structural features associated with adverse human health effects, 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.
Assessment conclusion
When the substance is used as notified, it is not expected to be harmful to human health or the environment according to the criteria under section 64 of the Act.
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.