New substances: risk assessment summary, new substances notification 19888

Official title: New Substances Notification No. 19888: Oxirane, 2-methyl-, polymer with oxirane, ether with alkyl triol, polymer with α-hydro-ω-hydroxypoly[oxy(methyl-1,2 ethanediyl)] and 1,1'-methylenebis [isocyanatobenzene] (Confidential Accession No. 19373-1)

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 oxirane, 2-methyl-, polymer with oxirane, ether with alkyl triol, polymer with α-hydro-ω-hydroxypoly[oxy(methyl-1,2 ethanediyl)] and 1,1'-methylenebis [isocyanatobenzene] (Confidential Accession No. 19373-1). The substance does not meet the Reduced Regulatory Requirements criteria according to the New Substances Notification Regulations (Chemicals and Polymers) because it contains terminal isocyanates.  

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 industrial adhesives. Potential uses may include industrial use in the fabrication of polyurethane foam, or in the production of paints, coatings and adhesives for industrial, commercial or consumer use.  

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 sediments. The substance is expected to be persistent in soil and sediments because it reacts with water to form high molecular weight, insoluble complexes that are resistant to degradation. The substance is not expected to bioaccumulate based on its high molecular weight, which will limit its ability to cross biological membranes.  

Ecological assessment

Based on its low water extractability (<2%), the substance is expected have low bioavailability. Therefore, a predicted no-effect concentration was not calculated given the low potential for ecological hazard.  

The notified and potential activities in Canada were assessed to estimate the environmental exposure potential of the substance throughout its life cycle. Environmental exposure from the notified activity is not expected as the substance will be highly removed during wastewater treatment. For potential activities such as use in industrial paints and coatings, adhesives, and polyurethane foam, environmental exposure is expected to be similar to that of the notified use. A predicted environmental concentration was not calculated due to the low potential for environmental exposure and low ecotoxicity.

Based on the low potential for ecotoxicity and environmental exposure, the substance is unlikely to cause ecological harm in Canada.  

Human health assessment

Based on the available hazard information on structurally related polymers, the substance is expected to have a low acute toxicity by the oral route (median lethal dose >2000 mg/kg body weight).  

When the notified substance is used as an industrial adhesive, consumers may come into contact with end-use products produced using 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 negligible given the low water solubility and expected efficient removal by waste water treatment, which results in little or no release to the environment. Potential uses of the substance include paints, coatings or adhesives for consumer use where direct exposure of the general population is expected to be mainly by dermal contact. However, systemic uptake is not anticipated because of the large molecular size of the substance. Indirect exposure of the general population from any potential uses is expected to be at levels that do not pose a concern, similar to that of the notified use.

Based on the low potential for exposure, 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 or for other identified potential activities, 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.