Airing dirty laundry: Students develop new way to measure plastics released in environment while washing clothes

Two undergraduate students researching pollution have helped develop a new way to measure how much plastic is released into the environment from laundering clothes – which may be contributing to plastic pollution choking the world's oceans. 

Hayley McIlwraith and Jack Lin, both second-year students, have been working on a Research Opportunity Program (ROP) project with Chelsea Rochman, an assistant professor in the department of ecology & evolutionary biology, and Miriam Diamond, a professor in the department of Earth sciences, to study the effectiveness of two different kinds of contraptions meant to trap microplastic fibres in the washing machine.

 “It’s not easy to count fibres, so most people have measured contamination by weight, but what these students have done is develop a novel method for counting that we can use to project how many fibres are being released into the environment,” says Rochman.

“We aim to publish our work to share our findings and new method, and we’ve also talked about writing a policy brief to share with people at Queen’s Park.”

Plastic pollution is a huge environmental problem, with approximately eight million metric tonnes entering the oceans each year. How much of that is microfibres from laundering textiles has yet to be determined, Rochman notes, making the students’ work all the more important.

Demonstrating the effectiveness of various mitigation technologies will inform government, industry and consumers. The hope is to make filters on washing machines standard, as they are in other parts of the world such as Japan.

“If you scooped up a handful of water from Lake Ontario, it is likely that it would contain microfibres,” says Diamond.

“I think what’s interesting about the project is that it has direct policy implications. There are concrete actions that can be taken by individuals, government and industry.”

From left,  Professor Miriam Diamond, Hayley McIlwraith, Assistant Professor Chelsea Rochman and Jack Lin (photo by Diana Tyszko)

The research being done by the students is part of a larger collaboration with federal and provincial departments, industry groups and the non-profit Ocean Conservancy, which contributed funds to help buy a special washing machine to test the filters.

Diamond says the broad partnership behind the research project increases the potential to move the results and findings from the university into a broader public forum.

Using fleece blankets as a test material, the students developed a method to collect the fibres in the wash water in small samples and then count them to determine the total amount.

“Instead of weighing the fibres – which doesn’t give an accurate amount – we put the samples on filter paper, took individual images and stitched them together, and then we counted the fibres in the overall image, giving us a count,” says Lin.

“It’s really amazing to be part of something like this that will have a real life impact.”

McIlwraith expected her second-year studies would involve reading textbooks and memorizing material, not collecting data and doing original research.

“This is an experience I didn’t expect to have so soon, and I really love it. In class we have labs, but the methods are already established, and we just follow the instructions. To develop an experiment from scratch is really special.”

The work being done by the students under this project demonstrates the opportunities available to undergraduates at the University of Toronto, adds Rochman.

“We have lots of different versions of ROP programs, and in the typical case, a student comes in and works with a grad student and follows a recipe. But Jack and Hayley have really led this project, and these opportunities exist for other students as well.”

Eligible students will have their next chance to participate in the Research Opportunity Program when courses for the 2018 summer term and 2018-19 fall-winter terms are announced next month.