Fuqing is one of the centers of a booming industry that over two decades has transformed this country into the biggest producer and exporter of seafood in the world, and the fastest-growing supplier to the United States.
But that growth is threatened by the two most glaring environmental weaknesses in China: acute water shortages and water supplies contaminated by sewage, industrial waste and agricultural runoff that includes pesticides. The fish farms, in turn, are discharging wastewater that further pollutes the water supply.
“Our waters here are filthy,” said Ye Chao, an eel and shrimp farmer who has 20 giant ponds in western Fuqing. “There are simply too many aquaculture farms in this area. They’re all discharging water here, fouling up other farms.”
Farmers have coped with the toxic waters by mixing illegal veterinary drugs and pesticides into fish feed, which helps keep their stocks alive yet leaves poisonous and carcinogenic residues in seafood, posing health threats to consumers.
But that growth is threatened by the two most glaring environmental weaknesses in China: acute water shortages and water supplies contaminated by sewage, industrial waste and agricultural runoff that includes pesticides. The fish farms, in turn, are discharging wastewater that further pollutes the water supply.
“Our waters here are filthy,” said Ye Chao, an eel and shrimp farmer who has 20 giant ponds in western Fuqing. “There are simply too many aquaculture farms in this area. They’re all discharging water here, fouling up other farms.”
Farmers have coped with the toxic waters by mixing illegal veterinary drugs and pesticides into fish feed, which helps keep their stocks alive yet leaves poisonous and carcinogenic residues in seafood, posing health threats to consumers.
Work Cite
Barboza, David. "In China, Farming Fish in Toxic Waters." New York Times. N.p., 15 Dec. 2007. Web. 01 Dec. 2014.
Barboza, David. "In China, Farming Fish in Toxic Waters." New York Times. N.p., 15 Dec. 2007. Web. 01 Dec. 2014.
"The ocean is basically a toilet bowl for all of our chemical pollutants and waste in general," says Chelsea Rochman, a postdoctoral researcher at the University of California, Davis, who authored the study. "Eventually, we start to see those contaminants high up in the food chain, in seafood and wildlife."
For many years, scientists have known that chemicals will move up the food chain as predators absorb the chemicals consumed by their prey. That's why the biggest, fattiest fish, like tuna and swordfish, tend to have the highest levels of mercury, polychlorinated biphenyls (PCBs) and other dioxins. (And that's concerning, given that canned tuna was the second most popular fish consumed in the U.S. in 2012, according to the National Fisheries Institute.)
What scientists didn't know was exactly what role plastics played in transferring these chemicals into the food chain. To find out, Rochman and her co-authors fed medaka, a fish species often used in experiments, three different diets.
One group of medaka got regular fish food, one group got a diet that was 10 percent "clean" plastic (with no pollutants) and a third group got a diet with 10 percent plastic that had been soaking in the San Diego Bay for several months. When they tested the fish two months later, they found that the ones on the marine plastic diet had much higher levels of persistent organic pollutants.
"Plastics — when they end up in the ocean — are a sponge for chemicals already out there," says Rochman. "We found that when the plastic interacts with the juices in the [fish's] stomach, the chemicals come off of plastic and are transferred into the bloodstream or tissue." The fish on the marine plastic diet were also more likely to have tumors and liver problems
For many years, scientists have known that chemicals will move up the food chain as predators absorb the chemicals consumed by their prey. That's why the biggest, fattiest fish, like tuna and swordfish, tend to have the highest levels of mercury, polychlorinated biphenyls (PCBs) and other dioxins. (And that's concerning, given that canned tuna was the second most popular fish consumed in the U.S. in 2012, according to the National Fisheries Institute.)
What scientists didn't know was exactly what role plastics played in transferring these chemicals into the food chain. To find out, Rochman and her co-authors fed medaka, a fish species often used in experiments, three different diets.
One group of medaka got regular fish food, one group got a diet that was 10 percent "clean" plastic (with no pollutants) and a third group got a diet with 10 percent plastic that had been soaking in the San Diego Bay for several months. When they tested the fish two months later, they found that the ones on the marine plastic diet had much higher levels of persistent organic pollutants.
"Plastics — when they end up in the ocean — are a sponge for chemicals already out there," says Rochman. "We found that when the plastic interacts with the juices in the [fish's] stomach, the chemicals come off of plastic and are transferred into the bloodstream or tissue." The fish on the marine plastic diet were also more likely to have tumors and liver problems
Work Cite
"How Plastic In The Ocean Is Contaminating Your Seafood." New Hampshire Public Radio. N.p., 16 Dec. 2013. Web. 01 Dec. 2014.
"How Plastic In The Ocean Is Contaminating Your Seafood." New Hampshire Public Radio. N.p., 16 Dec. 2013. Web. 01 Dec. 2014.