A vendor at a fish market in Hong Kong.
Half of the world's seafood is raised on farms, and some of those fish are bound to get sick at some point. So fish farmers, just like animal farmers, are keen on dumping antibiotics — sometimes in huge quantities — in those fish pens to keep the population safe.
A discerning eater might want to know if the shrimp that hits the plate is laced with drug residues, given that some can cause antibiotic resistance and cancer. But a new study says there's no way to find out, given the sketchy state of seafood import monitoring.
"We import millions of tons of seafood, and the testing is minuscule," says David Love, author of a new study in Environmental Science and Technology on drug residues in seafood. Love, a project director at the Center for a Livable Future at Johns Hopkins University, looked at testing for veterinary drugs in seafood in the United States, Canada, Japan, and the European Union, and compared systems. The U.S. trailed the pack.
Europe inspects 20 to 50 percent of imported seafood. Japan inspects about 20 percent; Canada, 2 to 18 percent; and the U.S., just 2 percent. Love told The Salt: "We don't have enough information to assess the risk."
U.S. inspectors found just 24 violations a year on average, but Love says that's no reason to be reassured, because it's impossible to know how many tests are being done. What's more, the U.S. doesn't test for many drugs commonly used in acquaculture.
One they have detected is nitrofuran; it has been banned in the United States since 2002, because it causes cancer. The dye malachite green was also found, despite the fact that it's been banned for food use since 1983 because it is a suspected carcinogen.
These findings echo a report published by the Government Accountability Office last April. The GAO said the Food and Drug Administration should emulate European countries in requiring importing countries to monitor drug residues in seafood before it's imported.
The paltry data doesn't give shoppers much to go on at the seafood market, where 85 percent of fish and shellfish are imported, on average. But Love's survey found that seafood from Vietnam and China had the highest rate of inspection violations in the United States, followed by Indonesia, domestic products, Thailand, and India.
Independent programs like the Monterey Bay Aquarium's Seafood Watch offer some help, with guides that include sustainably farmed fish.
In the United States, environmental groups and consumer advocates have been pushing for a ban on the use of antibiotics in animal feed, because they increase the risk of antibiotic resistance to drugs used in humans.
And it recently looked like they were getting traction. Last year the FDA went so far as to issue a "Draft Guidance on the Judicious Use of Antibiotics in Food-Producing Animals" last year. That guidance proposed limiting use of the drugs to animal health, rather than to promote growth and weight gain.
"Based on our review, FDA believes the overall weight of evidence available to date supports the conclusion that using medically important antimicrobial drugs for production purposes is not in the interest of protecting and promoting the public health," then-FDA Deputy Commissioner Joshua Sharfstein said in a June 2010 press conference announcing the draft guidance.
But this week, the FDA appeared to take a step back. It rejected a petition that advocacy groups filed way back in 1999, asking the agency to ban non-medical uses of antibiotics in animal feed. No word from the FDA on whether this means that action on judicious use is in the works, or lost in the mists of bureaucracy.