Researchers tag 3,000 shellfish to study microplastics in B.C. waters

If you see a clam or oyster with a tag reading "experiment in progress" on a Vancouver Island beach this summer, don't touch them, a researcher says.

Those shellfish 3,000 of them are part of a Vancouver Island and University of Victoria experiment looking at microplastics in the B.C. marine environment.

The research is being supervised by Sarah Dudas, a VIU biology professor and Canada Research Chair in shellfish aquaculture ecosystem interaction and biology.

"Unfortunately, we don't know a great deal about how much microplastic is out there," Dudas told All Points West host Robyn Burns. "There's only a handful of studies that have been done within our region."

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Microplastics are any plastic smaller than five millimetres in any dimension but can be microscopic in size.

Dudas says a growing number of studies point to the harmful effects of microplastics on marine environments, especially for fish reproductive systems, and a goal of this experiment is to add to knowledge about these effects.

Microplastics can be found in cosmetics and toothpaste but are also generated by larger plastic objects breaking down in the ocean.

"Largely what we're finding are fibres," Dudas said of her previous microplastic research on juvenile salmonids.

"We're not finding a lot of the microbeads you hear about in cosmetics we're finding mainly fibres that come from washing your clothes or fibres that might be shed from ropes or other fabrics."

Dudas and her team will look at shellfish around Nanoose, Ladysmith, Desolation Sound and the west coast of Vancouver Island in addition to Baynes Sound, where she says 50 percent of B.C.'s shellfish aquaculture takes place.

"We wanted to get a good spatial spread throughout the province, but we also wanted to focus on areas where we have shellfish aquaculture," Dudas said.

"We're also taking some wld samples from Vancouver and Victoria, which are more urban locations, to get a point of reference for how much microplastic those animals have in them."

Dudas says the shellfish will be harvested in the fall and their flesh digested chemically to count the amount of microplastic in them.

With files from CBC Radio One's All Points West

To hear the full story, click the audio labelled:Uncharted waters: researchers tag 3,000 shellfish to study microplastics in B.C.