Researchers Are Now Finding ‘Shocking Numbers’ of Microfibers in Shellfish

Might need to floss after eating these. Photo: Philip A. Dwyer/Bellingham Herald via Getty Images

Canadian marine biologists have given seafood lovers yet another reminder that those $2 happy-hour oysters probably include microplastics as a bonus accoutrement, whether you requested them or not. A Vancouver Island University team studying shellfish in the Pacific Northwest spent the last year doing a “crime lab”–level investigation of what’s inside the region’s oysters and clams, and let’s just say, you won’t be reaching for the mignonette after reading this: They let shellfish feed on nutrients in the coastal waters for three months, dug them all up, and dissolved them using chemicals. They then filtered out biodegradable matter, and checked under a microscope for what was left. “Nothing” would be the ideal discovery here, but as you’re by now guessing, they found an alarming amount of plastic instead.

Pacific water samples have turned up troubling amounts of particles before — one found 9,200 of them per cubic meter in 2013, or what NPR describes as equal to “emptying a salt shaker into a large moving box.” Scientists call those “rather shocking numbers,” but this Vancouver team was able to trace not only the average number of particles in shellfish (eight per oyster or clam), but also which particles.

They ran them through “a fancy forensic machine used at police stations” to run threads through a database of possible matches. The results included plastics found in cosmetics and sold as beanbag filler, but others with fun names like Zeftron 500 and Wonder Thread — nylons used in synthetic clothes like your Patagonia fleece. Researchers say these had to come from washing machines. Threads detach during each load, and while filters catch a lot of them and wastewater-treatment plants stop most of the rest, enough still slip by to really gunk up the ocean — which, if estimates are right, will contain more pounds of plastic than fish by the year 2050.

If this doesn’t ick you out, biologists also add that it’s not just bottom-feeders that are eating all these microfibers: They’ll naturally “in turn be ingested by zooplankton and move up into the food chain.”

Biologists Now Find ‘Shocking’ Amount of Microfibers in Fish