New proposals for addressing microplastic pollution in the Great Lakes Region

By Nancy Goucher

Developing effective strategies to reduce future microplastic emissions and manage existing pollution is challenging. These tiny plastic particles come from diverse sources, including clothing fibers, tire wear, packaging, industrial processes, and the breakdown of larger plastics. Their widespread presence allows them to enter the environment through multiple pathways, complicating prevention efforts. Additionally, once released, most microplastics do not biodegrade and tend to accumulate. Removing them from water bodies remains neither cost-effective nor feasible with current technologies.

Compounding the issue, global waste management systems struggle to handle plastic waste. In Canada, less than ten per cent of plastic waste is recycled, while about 22 per cent is mismanaged—meaning nearly a quarter of the waste produced is not properly collected, disposed of, or recycled and is likely to end up in the environment. Meanwhile, plastic production is projected to double or even triple by 2050, further exacerbating the problem.

Figure 1: Canada’s mismanaged plastic rate is higher than the OECD average. Source: OECD 

In our last newsletter, we explored how European countries are adopting circular economy models to address plastics across their entire lifecycle—from design and reuse to repair and recycling. In this article, we’ll examine some proposed policy developments aimed at tackling microplastic pollution in the Great Lakes region, spanning both Canada and the United States. It does not include a review of existing policy or technical solutions.

Designating microplastics as a Chemical of Mutual Concern under the Great Lakes Water Quality Agreement

Microplastics have been nominated for consideration as a Chemical of Mutual Concern (CMC) under the Great Lakes Water Quality Agreement (GLWQA). If accepted by the governments of Canada and the United States, this designation would require the countries to collaborate on developing a strategy to reduce the presence and impacts of microplastics in the Great Lakes.

The GLWQA Process

The GLWQA, first signed in 1972, is a binational agreement between the United States and Canada designed to restore and protect the waters of the Great Lakes. In its 2012 update, the agreement introduced a process for designating Chemicals of Mutual Concern (CMC) under the newly created Annex 3.

Recently, Dr. Chelsea Rochman of the University of Toronto officially submitted a request for microplastics to be designated as a CMC. This initiated a two-step process, which begins with a high-level screening to determine whether the substance meets pre-determined criteria and should undergo further consideration. The second step would require a detailed assessment of the chemical’s environmental fate, sources, impacts, and existing policies.

Should microplastics be officially designated as a CMC, Canada and the United States would be required to develop a binational strategy for addressing microplastics in the Great Lakes. These strategies could include research, monitoring actions, and measures for reducing or eliminating the release of microplastics into the environment. Annex 3 of the GLWQA also recognizes the importance of a life-cycle management approach to addressing chemicals, so the strategy could consider all stages of the plastic life cycle, from extraction, through import or manufacture, distribution, use and disposal.

Michigan’s proposed regulations to strengthen microplastics monitoring and recycling

One Great Lakes state making strides in tackling microplastic pollution is Michigan. State representatives have introduced (but not yet passed) several bills to improve monitoring efforts:

• Bill 6163 (introduced November 2024) proposes a statewide microplastics research and monitoring plan, to be implemented in partnership with state agencies and local universities. Its goal is to better understand sources of microplastics and develop strategies to mitigate their impact on water systems.
• Bill 6164 (introduced November 2024) would establish a microplastics monitoring program for Michigan’s drinking water, requiring quarterly tests to identify contamination levels, sources, and types of microplastics. These efforts could pave the way for setting toxicity limits and other safety measures.
• HB 5902(introduced in July 2024) promotes a new approach to waste management referred to as extended producer responsibility. If passed, it would set recycling and material reduction targets and direct producers to pay for the collection, transportation, and management of packaging materials. Notable is a clause that would require producers to reduce the amount of packaging by 10 per cent in weight in two years, and 50 per cent within ten years. 

Both of the monitoring bills (6163 and 6164) have strong potential for success, with $2 million already allocated for microplastics work in the state.

Ontario’s efforts to add filters to washing machines

Ontario also introduced a bill in its last legislative session to reduce microplastic pollution. Bill 279, Environmental Protection Amendment Act (Microplastics Filters for Washing Machines) would have amended the Environmental Protection Act to require new washing machines to be sold with microplastic filters. However, debate on the bill stalled, and it died on the order paper in February 2025 when an early election was called.

Looking Ahead

With the Great Lakes home to more than 30 million people and countless wildlife species—and contributing billions of dollars to the economies of Canada and the US—addressing microplastic pollution is a critical priority. While some progress is being made, more comprehensive management strategies are needed to mitigate risks and prevent further harm.

By implementing robust monitoring, harmonized regulations, and basin-wide strategies, decision-makers can ensure the long-term protection of one of North America’s most vital freshwater ecosystems.