Seeing Science: You Are What You Eat

Tiny threads of plastics are showing up in Pacific oysters and razor clams along the Oregon coast—and the yoga pants, fleece jackets, and rainproof clothing that Pacific Northwesterners love to wear are a source of that pollution, according to a Portland State University study.

Britta Baechler, a Ph.D. student in PSU’s Earth, Environment and Society program, and Elise Granek, a professor of environmental science and management, studied microplastics in Pacific oysters and razor clams with support from Oregon Sea Grant. While they found plastics in all but two of 300 samples from 15 sites between Clatsop and Gold Beach, spring oysters contained by far the most.

The researchers concluded that synthetic clothing worn in winter and spring may have been a factor. When this clothing goes through the wash, plastic threads shed from it—up to 700,000 strands per load of laundry—and travel through wastewater out to estuaries, where the tide meets the stream and oysters are feeding and growing. Special washing machine filters might help interrupt this process, Granek said, but they are still in the early stages of development.

More research needs to be done to determine what effect microplastics have on the oysters and clams, as well as the humans who eat them.

1. Plastic polymer-based fabrics are used to make popular clothing items like raincoats, fleece and stretchy pants.

2. When these go in the wash, plastic threads shed from them.

3. Threads from clothing and other sources travel out with the wastewater to the Oregon coast.

4. They end up in shellfish, particularly spring Pacific oysters that have fed and grown when people are wearing—and washing—jackets and winter clothing.