By Nate Seltenrich

As the “Fish-SMART” signs on local piers warn, the tissues of fish reeled in from San Francisco Bay waters can contain mercury or PCBs, but a new RMP report reminds us of a third contaminant of concern to human health: dioxins. The report, due out in October 2018 and prepared by staff of the San Francisco Estuary Institute and the SF Bay Regional Water Quality Control Board, confirms that while levels of this toxic contaminant in sediments nearshore have declined somewhat in the last few decades, dioxins persist in the food chain in fish such as white croaker. Dioxins are ending up in the Bay via atmospheric fallout and runoff. “Basically any burning process can potentially produce dioxins,” says SFEI scientist Don Yee, and even if individual sources aren’t large “it all adds up.”

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Dioxins Are Sticking Around Nearshore and in Fish, RMP Reports

By Nate Seltenrich

As the “Fish-SMART” signs on local piers warn, the tissues of fish reeled in from San Francisco Bay waters can contain mercury or PCBs, but a new RMP report reminds us of a third contaminant of concern to human health: dioxins. The report, due out in October 2018 and prepared by staff of the San Francisco Estuary Institute and the SF Bay Regional Water Quality Control Board, confirms that while levels of this toxic contaminant in sediments nearshore have declined somewhat in the last few decades, dioxins persist in the food chain in fish such as white croaker. Dioxins are ending up in the Bay via atmospheric fallout and runoff. “Basically any burning process can potentially produce dioxins,” says SFEI scientist Don Yee, and even if individual sources aren’t large “it all adds up.”

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About the author

Nate Seltenrich is a freelance science and environmental journalist who covers infrastructure, restoration, and related topics for Estuary. He also contributes to the San Francisco Chronicle, Sonoma and Marin magazines, the journal Environmental Health Perspectives, and other local and national publications, on subjects ranging from public lands and renewable energy to the human health impacts of climate change. He lives in Petaluma with his wife, two boys, and four ducks. www.nate-reports.com

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