Filters on Washing Machines Significantly Reduce Microfibre Pollution Finds New Study

Installing filters on washing machines is a simple and effective way to catch the microscopic particles in our clothes shed, finds a study released this month.

As we’ve mentioned before, every time you wash a load of laundry, anywhere from a few hundred thousand to millions of microfibres come off of the fabrics and go down the drain. These microfibres are too small to be captured at wastewater treatment plants ['WWTP'] so end up in the environment.

Washing clothes releases half a million tonnes of plastic microfibres into the ocean every year, equivalent to more than 50 billion plastic bottles.

A new scientific study, which was a collaboration between Georgian Bay Forever (GBF) and the Rochman Laboratory at the University of Toronto, is the first application of washing machine filters at a community scale.

Results from the study prove that washing machine filters prevent harmful microfibre waste from entering waterways.

Lead author, Lisa Erdle, who is a PhD candidate at the University of Toronto and worked on the study with three other colleagues explained that 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, Ontario, Canada to attach an external microfibre-catching filter to their home washing machines. This was the first study to put filters into people’s homes and test whether they are effective at the scale of a community.

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 number of microfibres showing up. Erdle expected to see about 10% decrease as 10% of households were used. The actual decrease was 41% though, far greater than anticipated.


Above image: Infographic based on findings from the report, Washing Machine Filters Reduce Microfiber Emissions: Evidence From a Community-Scale Pilot in Parry Sound, Ontario. By Erdle, L, 2021.

Key Evidence from the Community-Scale Pilot

  • Filters were installed in 10% of homes but microparticles in the local WWTP effluent were reduced by 41%.
  • Except for two fragments, all the particles collected in the WWTP samples were microfibers.
  • The town involved in the study applies WWTP sludge as fertiliser, so the filters also reduced emissions to land ecosystems.
  • Many households were turned away from the study due to lack of space for an external filter

Writing the Use of the Filters into Law

Brooke Harrison, a project coordinator at Georgian Bay Forever, co-authors of the study,  and Lisa Erdle both agree that the solution to microfibre pollution is straightforward.

Microfibre-catching filters should be built into all new washing machines.

They explained that dryers already have a filter that captures some of the fibres and now washing machines need one. 

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

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.

Politicians across Europe Tackle Microfibre Pollution

In 2020, France became the first country in the world to pass legislation requiring all new domestic washing machines to have a microfibre filter fitted, as standard, from the beginning of 2025.

Earlier this year, Xeros was honoured to join policy experts at the launch of the UK All-Party Parliamentary Group for Microplastics report in Parliament. This report calls on Westminster to pass legislation mandating microfibre filtration in all domestic and commercial washing machines by 2025.

In November 2021, Alberto Costa MP is introducing a Bill in Parliament that requires manufacturers to fit microplastic catching filters in all new washing machines.

Mark Nichols, CEO of Xeros Technologies PLC shared his thoughts on the world starting to take legislative steps in the fight against plastic microfiber pollution.

At Xeros we have long held that microfibre filtration must become mandatory in domestic and commercial washing machines and garment finishing equipment.
Effective microfibre filtration in washing machines is the quickest and most cost-effective way to mitigate the release of microplastic from laundry to aquatic environments.
We're very proud to have worked with the APPG Microplastics compiling its report and we whole heartedly support all its recommendations to UK Government.

An In-Built Solution to Microfibre Pollution

XFiltra in Drawer v0.2Xeros has a practical solution to stop nearly all microfibres from getting into our seas. 

XFiltraTM, an innovative washing machine filtration technology, can now be easily integrated by all washing machine manufacturers.

This filter is available for both domestic and commercial washing machines and is designed to be simple and easy to use. As it is integral to the machine, it does not take up unnecessary space making it accessible for most households..

XFiltra has been identified as the most effective device at preventing microfibre release from washing machines.

Research conducted by the University of Plymouth tested six devices designed to capture microfibres: three washing machine filters plus laundry bags and balls, on mixed wash loads of synthetic and synthetic/cotton blend garments.

The Xeros filter performed best. The prototype used in the study caught 78% of all microfibres but the latest generation capture more than 90% of all microfibres.

To read the full report by GBF and the University of Toronto, click the following link. Washing Machine Filters Reduce Microfiber Emissions: Evidence From a Community-Scale Pilot in Parry Sound, Ontario

Main image: 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)