Microtrash Tiresome for Watersheds

By Jacoba Charles

As many as 30 particles of microplastic smaller than five millimeters in diameter are discharged with every liter of stormwater, according to a report published by the San Francisco Estuary Institute and 5Gyres last October. “A big proportion of what we saw were black rubbery fragments,” says SFEI’s Diana Lin, a lead author of the report. Apart from these likely biproducts of tire wear and tear, hair-like threads of fiber were the other main type of microplastics found. The latter break down from trash like cigarette butts and abandoned clothing. The study sampled 12 tributaries that feed into the Bay. “I am really encouraged by the level of interest this issue is getting,” says Chris Sommers, a reviewer of the study for the Regional Monitoring Program. Researchers are following up on this study with further investigations into the biological and ecological effects of microplastics.

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About the author

Jacoba Charles is a naturalist and science writer. Her first article, at age eight, was about the behavior of ducks as observed from the roof of her family’s barn. It went unpublished. She later graduated from the Columbia School of Journalism (2007). In addition to writing for Estuary News, her work has appeared in The New York Times, Salon, and Modern Farmer, Bay Nature, Marin Magazine, and various literary publications. Her botany blog can be found at flowersofmarin.com and her website is jacobacharles.com. She lives in Petaluma with her family.

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