Unconstitutional and Not Based in Science? The Federal Regulation of Plastic as a Toxic Substance

environmental protection

On May 12, 2021, after a period of public and stakeholder consultation, the Canadian government added “plastic manufactured items” to the List of Toxic Substances at Schedule 1 of the Canadian Environmental Protection Act, 1999 (the “CEPA”). The Order defined “plastic manufactured items” as “any items made of plastic formed into a specific physical shape or design during manufacture, and have, for their intended use, a function or functions dependent in whole or in part on their shape or design.” These items include final products or components of products.

On May 19, 2021, the Responsible Plastic Use Coalition (RPUC), a group now comprised of 33 plastics industry leaders, brought a lawsuit seeking judicial review of the federal government’s decision to add “plastic manufactured items” to CEPA’s List of Toxic Substances. The lawsuit calls for the removal of “plastic manufactured items” from CEPA’s Schedule 1.


Under CEPA, substances are considered ‘toxic’ if they can enter the environment in a quantity or concentration that (a) causes or may cause immediate or long-term harm to the environment or its biological diversity, (b) constitutes or may constitute a danger to the environment on which life depends, or (c) constitutes or may constitute a danger to human life or health.

The federal government can add substances to the List of Toxic Substances under Schedule 1 of CEPA and make regulations with respect to the control of the substances added. This includes, but is not limited to, regulating the commercial, manufacturing or processing activities that may release the substance, or regulating the importing, manufacturing or use of products containing the substance.

Although often referred to as a “plastic ban”, adding “plastic manufactured items” to Schedule 1 of CEPA does not in itself ban or restrict any items or specify or preclude any particular management approaches to addressing plastic waste. The RPUC, nonetheless, argues that the Order adding these items to Schedule 1 is unconstitutional, exceeds the jurisdiction of the federal government, and is also wrong in law, unreasonable and scientifically inaccurate.


Is the Order Constitutional?

The RPUC argues that the Order designating “plastic manufactured items” as a toxic substance is unconstitutional because it extends federal regulatory powers to areas within the jurisdiction of the provinces – particularly, waste management.

Under the Constitution Act, 1867, specific legislative powers are listed as either federal or provincial. The “environment” is not within the exclusive jurisdiction of either the provinces or the federal government and both can regulate with respect to this area.

CEPA is unique in that, despite being a statute regulating environmental matters, it is grounded in the federal government’s power over criminal law rather than over the environment. The Supreme Court of Canada affirmed Parliament’s authority to regulate toxic substances under the criminal law power in the case R. v. Hydro-Québec. However, the Court also expressed concern with the possibility that this would allocate legislative power on environmental pollution exclusively to Parliament.

Relying on R. v. Hydro-Québec, the RPUC argues that the Order is too broad and defies the narrowness of federal regulation over toxic substances. The category of “plastic manufactured items” is “sweeping”, containing thousands of individual items.

In response to public comments on the Order when it was proposed, the Canadian government has stated that the broadness of the category is appropriate because the Science Assessment of Plastic Pollution (the “Science Assessment”) found that plastic pollution arises from various sources.  Additionally, all “plastic manufactured items” have the potential to become pollution.

Are “Plastic Manufactured Items” a “Substance” as Defined by CEPA?

The RPUC argues that the federal government exceeded its authority in listing “plastic manufactured items” under CEPA because these items are incapable of assessment for toxicity under the authority of CEPA. CEPA’s definition of “toxic substance” is limited to singular items rather than broad, descriptive categories like “plastic manufactured items”. It also argues that “plastic manufactured items” cannot be identified as a “class of substances” under CEPA.

Is the Order Science-Based?

The RPUC further argues that the Order is unreasonable because it is not based in science. It highlights what it deems to be various scientific shortcomings with the Science Assessment prepared by the Canadian government. The RPUC argues that the Science Assessment is a literature review rather than a scientific, risk-based assessment, which should include testing of whether plastics are toxic under CEPA. Additionally, the existing evidence about the health impacts of microplastics is unclear and contradictory and does not identify any risk to human life or health.

According to the Canadian government, the Science Assessment confirms that macroplastics can cause physical harm to the environment and habitats per CEPA’s definition of toxic substances. Nonetheless, the government has acknowledged that more research is needed in relation to certain plastics and their harms (e.g., compostable plastics).


Plastic pollution can be found in Canada’s shorelines, waters, land, animals, and air. New scientific studies continue to elaborate on the negative impacts of plastic pollution on the environment while links of harm to humans are still being studied. Recently, the Ellen MacArthur Foundation has called for a UN treaty on plastic pollution to develop an international binding approach to the problem of plastic pollution rather than relying on voluntary initiatives.

The federal government has recognized that “plastic pollution is an issue that requires immediate action in Canada.” By including “plastic manufactured items” on the List of Toxic Substances, the federal government has embraced the precautionary principle found in CEPA’s preamble which states that “where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.” Public interest groups such as Environmental Defence Canada and Oceana Canada have requested to intervene in the RPUC lawsuit to defend the government’s Order.

On the other hand, the federal government’s decision to list “plastic manufactured items” under Schedule 1 is likely to undergo significant court scrutiny given the RPUC’s robust claims. If successful, the lawsuit may lead to a reckoning of how Canada can effectively and constitutionally act to eliminate plastic pollution. It might require other orders of government to swiftly use their regulatory powers in addressing this growing issue.

Written by Denisa Mertiri and Madison Bruno.

For questions or further consultation with an environmental lawyer, please contact Denisa Mertiri at denisa@greenearthlaw.ca.