Canada Siloxane Evaluations
In January 2009, Environment Canada identified D4, D5, and D6 as priorities for regulatory evaluation on the basis of hazard screening criteria. Further to a comprehensive screening assessment of all three materials, Canada has not imposed any use restrictions or concentration-based restrictions on the use of D4, D5, or D6 for any product in Canada.
Environment Canada and Health Canada have also evaluated linear siloxanes, including L2, L3, L4, and L5 and concluded that these siloxanes are not entering the environment in a way that constitutes a danger to human health or the environment. Consequently, L2, L3, L4, and L5 are not subject to any regulatory restrictions in Canada.
In November 2008, Environment Canada conducted a screening assessment on D6. Based on this assessment, Canada’s Environment Minister concluded that “D6 is not entering the environment in a quantity or concentration or under conditions that is harmful to the environment.”
For D5, the Canadian Environment Minister established a first-ever Board of Review in which independent scientists chosen by the Minister reviewed the available science to determine whether D5 could pose a risk to the environment. Following a scientific review process that included formal hearings and a rigorous examination of all the relevant scientific information related to D5’s behavior in the environment and any potential danger posed by the substance, the Board concluded in October 2011 that “siloxane D5 does not pose a danger to the environment or its biological diversity.” Furthermore, the Board concluded that, “based on the information presented, siloxane D5 will not pose a danger to the environment or its biological diversity in the future.”
In February 2012, the Canadian Environment Minister accepted the Board of Review’s findings and removed D5 from a proposed list of toxic substances under the Canada Environmental Protection Act (CEPA).
In addition, Environment Canada, having reviewed the environmental data available for D4, has not imposed any product use or concentration restrictions on the use of D4 in any application; they only require certain facilities that use D4 to prepare a pollution prevention plan to minimize the release of D4 in industrial effluents.
In 2015, Environment Canada and Health Canada published their final screening assessment for L3, which concluded that the substance is not entering the environment in a way that constitutes a danger to human health or the environment. As such, L3 is not subject to any regulatory restrictions in Canada. Based on Canada’s determination, the states of Maine (2017) and Minnesota (2019) both removed L3 from their chemicals of concern lists.
In addition, in 2019, Canada released a draft risk assessment of L2, L4, and L5. The Canadian Minister of the Environment and the Minister of Health concluded these materials are not entering the environment in a quantity or concentration or under conditions that constitute a danger to the environment, nor a risk to human health. Canada has not proposed any regulatory restrictions on the use of any of these materials.
The GSC continues to urge regulators around the world to adopt a risk-based approach to evaluating silicone substances. Because of the significant benefits these materials provide to consumers and society, it is important that any regulatory determinations be based on real-world exposure and all available relevant scientific data.