June 7, 2019 | Science, Society
A water pump hums in the background and a light breeze runs throughout the cattails as Kaitlynn Weisgerber’s net breaks the mirrored surface of the northeast Edmonton stormwater pond.
She may be hundreds of kilometres away from the nearest ocean, but the invertebrate, water and soil samples the fourth-year biological sciences student is collecting could be tied to the plastic pollution crisis in the world’s largest bodies of water – and in the bodies of the animals that call them home.
Kaitlynn is one of 10 student research assistants who have been working with Dr. Matthew Ross, assistant professor of chemistry, and Dr. David Locky, associate professor of biological sciences, over the past three summers on a project that centres on microscopic fragments of plastic (the size of a sesame seed and smaller) in Edmonton’s waterways.
“Most people don’t understand that the vast majority of the plastic we use is never recycled,” says Matt. “Plastic doesn’t biodegrade back to its original components – it breaks down into smaller and small pieces, and those pieces have to end up somewhere.”
That somewhere could be in freshwater systems so in 2017, with support from Matt’s Natural Sciences and Engineering Research Council (NSERC) Discovery Grant and a MacEwan University Strategic Research Grant, he and David began looking in the North Saskatchewan River.
Since then, they’ve expanded the microplastics search to over 50 sites in and around Edmonton, including natural wetlands and several of the city’s stormwater ponds. The bad news?
“We found microplastics in every body of water we tested,” says David.
Dr. David Locky, Dr. Matthew Ross, and student research assistants Kaitlynn Weisgerber, Tianna Groeneveld and Danielle Molenaar on the first of the sites the team will visit this summer.
But the news isn’t all bad. Knowing the plastic is present gives the researchers a place to start looking for a way to stop the flow of plastics into our waterways. Now, they’re collecting additional samples of water and sediment to determine where the plastic is coming from, how it gets into freshwater systems, and if the microplastics get trapped in sediment or travel downstream in water that is ultimately transported back into the oceans.
Matt and David have also started looking to see if microplastics are making their way into the aquatic invertebrate species (insects, snails, leeches) that live in freshwater systems. “Because invertebrates represent the bottom of food webs, if they are ingesting microplastics – either directly or indirectly – it could have implications for species further up the food chain,” David explains.
And this spring, student research assistants are once again out into the field with Matt and David collecting additional samples of water and sediment, and the first invertebrate samples, from a variety of sites around Edmonton. They’ll bring the samples back to the lab where they will use chemical reactions to eliminate organic materials, and put what remains under a microscope to look for evidence of microplastics – typically fibres from synthetic clothing or broken-down pieces of larger plastics. Then, the work of analyzing the data and writing up the results continues.
Streamlining the process
Visually detecting the tiny plastic fragments under a microscope is time-consuming work, so Matt has also teamed up with colleague Dr. Roland Lee, assistant professor in chemistry, in a spin-off project to develop new lab tools and methods.
The research – the first of its kind in Alberta and among the first in Canada – simply wouldn’t be possible without help from students, who are funded by NSERC Undergraduate Student Research Awards and MacEwan University Undergraduate Student Research Initiative grants.
And though it will take time to answer the questions Matt, David and their students are asking, there’s no doubt the work is important for many people, including those of us who might not realize that what we do in landlocked Alberta could have consequences in the world’s oceans.
“We see pictures of turtles and whales with stomachs full of plastic and it may seem far away,” says Matt. “But plastic pollution can have impacts on the local environment too. We’re hoping to figure out where it’s coming from so we can better control those sources and keep plastic waste out of the environment here – and ultimately downstream and in the oceans as well.”
Our alumni in action
Marine biologist and MacEwan alumna Dr. Jennifer Lavers (Bachelor of Science Transfer, ‘01) recently published research that shows there may be far more plastic along the world’s coastlines than we think.