Filters on laundry machines lead to 'significant' cut in microfibre pollution, Ontario study finds

Installing filters on washing machines could be a simple and effective way to catch the microscopic particles our clothes shed, says a new study from the University of Toronto.

Nearly 100 homes in Parry Sound, Ont. had special filters installed for 2 years

Lisa Erdle poses with a jar of microfibre lint in her U of T lab - all of it kept out of waterways thanks to a study that saw special filters installed on washing machines in Parry Sound, Ont. (Kate McGillivray/CBC)

Installing filters on washing machines could be a simple and effective way to catch the microscopic particles our clothes shed, according to a study released this week by the University of Toronto and nonprofit Georgian Bay Forever. 

Every time you wash a load of laundry, anywhere from a few hundred thousand to millions of microfibres come off of the fabrics, says lead study author Lisa Erdle.

Erdle, who is a PhD candidate at U of T and worked on the study with three other colleagues, says the microfibres are shed by both synthetic and treated natural fabrics like cotton and wool, making their way into the water and air, and ultimately, into our bodies. 

The team's study recruited 97 households in Parry Sound, Ont. to attach a special microfibre-catching filter — which costs about $200 — to their home washing machines. 

"This is the first study that really put these filters into peoples homes and tested whether they are effective at the scale of a community," Erdle told CBC Toronto. 

By testing wastewater arriving at the town's treatment plant before and after the filters were installed, the research team was able to track a "significant reduction" in the amount of microfibres showing up, she said. 

The filters used in the study are separate from the laundry machine itself, making them impractical for smaller spaces and stacking washers and dryers. The study's authors are instead suggesting built-in filters be installed in all new machines. (Submitted by Brooke Harrison )

"Since we had about 10 per cent of [Parry Sound] households, we thought we would see about a 10 per cent decrease. We saw an even greater decrease than that," Erdle said. 

That extra decrease could be because growing awareness about microfibres led people to change their washing habits, "but we don't necessarily know," she continued. 

Effect on human health still unclear 

Microfibres shed from textiles have been building up in the world's waterways for decades now, spurred in part by the rising popularity of high-shed fabrics like polyester

Despite filtering at water treatment plants that catches many of them, Erdle and her team cite research that shows that some 4.8 million tonnes of synthetic microfibres have made their way into "waterways and terrestrial environments" since 1950 — a number that would be much higher if it included fibres from treated natural textiles like cotton and wool. 

From there, says Erdle, the particles end up in the air we breathe, the water we drink, and in animals we consume. 

Georgian Bay Forever says recent tests were unable to locate a single fish in the Great Lakes that did not contain microfibres. (Lisa Erdle)

"We don't know a lot about how microfibres are affecting humans, that research has just begun," she said. 

"But it's kind of gross that we're eating and drinking and breathing in these fibres from our clothing that could be having an effect." 

There has, however, been research on the effect of the fibres on fish, showing an impact on growth and feeding behaviours, as well as liver damage. 

That's important information for people studying Ontario's Great Lakes, where microfibres are now the most common type of microplastic polluting the water, says Brooke Harrison, a project coordinator at Georgian Bay Forever.

The tiny fibres are so common that these days, it's impossible to find a sample from the lakes — including fish and sediment — that doesn't contain them.

"Every single fish we're seeing… has microfibres in them," said Harrison. "So you can imagine, up the food chain, that ultimately leads to humans." 

Bill introduced in Ontario to mandate filters 

The solution, say Harrison and Erdle, is straightforward: require that microfibre-catching filters are built into all new washing machines. 

"Dryers already have the filter. Now washers need the same thing," said Harrison. 

Erdle says it's an idea that's already gaining global momentum, citing a law passed in France requiring filters in all new laundry machines starting in 2025. 

Other jurisdictions, including California and Ontario, are mulling a similar move — prompting them to reach out to Erdle's team for details on their research. 

"This study has really put Parry Sound on the global map for microplastic pollution. Legislators around the world are looking for results on washing machine filters," she said. 

Erdle at work at Parry Sound's water treatment plant. About 10 per cent of households in the community agreed to have a filter installed for the study. (Submitted by Lisa Erdle)

This past spring, MPPs Jessica Bell and Arthur Ian introduced a bill in that would require filters in new washing machines in the province of Ontario. 

"It makes so much sense," Bell told CBC Toronto in an interview earlier this month. "I can't think of any good reason why we wouldn't do that." 

The bill has yet to go to the second reading stage, and won't until after the upcoming June provincial election at a minimum, says Bell.

But, she adds, the government could make a change like this "any day" — if it wanted to. 

"Often the best way to make law is to introduce amendments to existing laws," said Bell. "They could introduce this as a schedule to any of their massive omnibuses."

In a statement to the CBC, a spokesperson for Ontario's environment ministry described different steps the government is taking to reduce plastic pollution in rivers and lakes, including a partnership with Ottawa to protect Great Lakes water quality.

"Since appliance manufacturing is global, implementation of such initiatives may best be addressed at national or international levels to be most effective," the statement concluded.