By Betty Yu

HALF MOON BAY (KPIX 5) – If you’re in the market for fresh fish, there’s a chance it didn’t eat the healthiest dinner.

A new study out of UC Davis found that one out of four fish bought at random fish markets in Half Moon Bay and Princeton turned out to have confirmed bits of plastic and mostly fibers in their guts. Researchers sampled 64 fish including salmon, anchovy, bass and tuna.

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They also tested fish from Indonesian waters and found that they had only plastic in their guts but no synthetic fibers.

Researchers suspect that the fibers found in California fish come from clothing. Water from washing machines goes to wastewater treatment plants and then empties into the ocean. Because of bad filtering systems, the fish end up eating fibers.”

“I always thought – hey you know it washes, it goes down a special drain it goes into a treatment plant. I didn’t realize it’s being dumped back out here,” said William Crom, a sport fisherman. “They really need to step up their game and get better filtration systems because that damages the fish for us.”

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Crom said the findings won’t stop him from eating fish, and researchers say it shouldn’t. The health benefits of eating seafood generally outweigh any costs.

Felipe Preciado of the Half Moon Bay Fish Market said most people don’t eat fish whole so he’s not too worried.

“I’m more concerned about they do a little more research to see if it is really affecting the meat, because what they found is that it’s just in the intestines in the guts,” Preciado said.

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Researchers are still studying whether the chemicals in plastic can transfer into the meat of the fish on your plate.