Jay Davis didn’t expect much from a pilot test for PCBs in silversides and topsmelt that live on the edges of the San Francisco Bay. The monitoring program he heads only ran the test on these small fish, which rarely grow more than 3-4 inches long, because it was simple to piggyback on an existing study of mercury in the same fish samples. “I thought it wouldn’t really be a big deal,” says Davis, who is lead scientist for the Bay Regional Monitoring Program (RMP). PCBs, a toxicant linked to cancer, accumulate in fat as bigger creatures eat littler ones, so Davis assumed concentrations would be lower in small fish than in larger sport fish. The pilot study revealed the opposite was true. “This is why we do measurements,” he says.

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Small Fish Test Helps Target PCB Clean Up

Ben Greenfield and Rachel Allen, SFEI

Jay Davis didn’t expect much from a pilot test for PCBs in silversides and topsmelt that live on the edges of the San Francisco Bay. The monitoring program he heads only ran the test on these small fish, which rarely grow more than 3-4 inches long, because it was simple to piggyback on an existing study of mercury in the same fish samples. “I thought it wouldn’t really be a big deal,” says Davis, who is lead scientist for the Bay Regional Monitoring Program (RMP). PCBs, a toxicant linked to cancer, accumulate in fat as bigger creatures eat littler ones, so Davis assumed concentrations would be lower in small fish than in larger sport fish. The pilot study revealed the opposite was true. “This is why we do measurements,” he says.

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About the author

Robin Meadows is an independent science journalist in the San Francisco Bay Area. She’s a water reporter at Maven's Notebook, a California water news site, and contributor to Chemical & Engineering News, Ka Pili Kai, KneeDeep Times, and Scientific American. Robin is also a Pulitzer Center grantee, an Institute for Journalism & Natural Resources fellow, a contributor to The Craft of Science Writing, a mentor with The Open Notebook, and a UC Santa Cruz Science Communication Program graduate. Find her on Tumblr and Twitter.

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