The Hidden Dangers: What Happens When Restaurant Owners Buy Frozen Shrimp From Unapproved Vendors?

Should you buy farmed shrimp at all?

The shrimp business can be extraordinarily lucrative when its done on a large scale. A medium-sized shrimp farm in Southeast Asia can produce close to a million pounds of shrimp per year—a powerful incentive for farmers to maximize production.

But evidence shows that those vast overseas operations may use antibiotics similar to those that humans rely on to treat infections. For example, they may use tetracyclines. Although many countries permit the use of antibiotics for shrimp farming, foreign shrimp destined for the U.S. market are not allowed to be raised using them and it is illegal to import shrimp containing them into this country. In addition, overseas shrimp farmers may also be using pesticides such as toxic organophosphates, and antifungals such as Gentian violet, which may cause cancer. Not only arent those chemicals permitted by the U.S. for shrimp farming, but they can also put your health at risk and damage the environment.

One reason farmers turn to antibiotics is that shrimp in crowded farms are extremely susceptible to diseases, such as Early Mortality Syndrome (EMS), which can wipe out entire harvests. In 2013, EMS was reported to have reduced Thailands shrimp output by 50 percent. But theres a strange illogic here: According to Donald Lightner, Ph.D., a professor of veterinary science and microbiology at the University of Arizona, EMS doesnt respond to antibiotics. In fact, our experts say that some of the most devastating shrimp diseases are caused by viruses, against which antibiotics dont work.

Its the FDAs job to inspect shrimp coming into the U.S. to make sure it doesnt contain any drugs or chemicals that arent permitted in imported shrimp. But in our tests, of the 205 raw farmed imported shrimp samples, 11 samples from Vietnam, Thailand, and Bangladesh tested positive for one or more antibiotics: Nine tested positive for oxytetracycline, three contained enrofloxacin, and two contained sulfa antibiotics. (Consumer Reports is calling on the federal government to make shrimp safer for American consumers.)

The contaminated samples were purchased at the following retailers in March, 2014: Albertsons, Costco, Frys Marketplace, Hy-Vee, Kroger, Sprouts Farmers Market and Walmart. (In nearly all cases we also purchased raw farmed imported shrimp from those outlets that tested negative for any antibiotics.) Consumer Reports is not alleging that any of the retailers from which we purchased the 11 raw farmed shrimp that tested positive for antibiotic residues violated any laws. It is the FDA, not local retailers, that is charged with enforcing the law that prohibits importing shrimp containing antibiotics. According to the FDA, if those drugs had been detected in even one shrimp sample, the entire shipment would have been refused entry into the U.S. Consumer Reports has shared our test results with the FDA and asked them to investigate (For more details about our test results, visit greenerchoices.org/shrimp.)

The small quantities of antibiotics we found probably wouldnt affect a typical consumers health, says Michael Crupain, M.D., M.P.H., director of the Consumer Reports Food Safety and Sustainability Center. But farming shrimp with antibiotics has the potential to cause harm down the road: Antibiotics dont kill off all bacteria, and those that do survive can multiply. If those resistant bacteria cause infections, certain antibiotics that once treated them will no longer work. Whats more, resistance can be transferred to other bacteria, including those that cause common human infections. In fact, the national Centers for Disease Control and Prevention estimates that antibiotic-resistant infections contribute to 23,000 deaths and more than 2 million illnesses in the U.S. each year.

We found the antibiotic-resistant bacteria MRSA on six samples of farmed shrimp from Vietnam, Bangladesh, and Ecuador, and on one wild sample from the U.S. MRSA can make you sick. “Its spread through contact, so if MRSA gets on your skin while youre preparing raw shrimp, it can potentially cause an infection, especially if you have an abrasion or cut,” Crupain says. MRSA causes serious skin and blood infections. And about 11,000 people in the U.S. die as a result of MRSA each year. We found more MRSA on shrimp than we found in our studies of pork, chicken, and ground turkey.

So which farmed shrimp should you buy? Consumer Reports recommends buying farmed shrimp raised without chemicals, including antibiotics. That can include shrimp farmed in large outdoor ponds that mimic the natural habitat or in tanks that constantly filter and recycle water and waste. Consumer Reports has evaluated organizations and stores that certify whether farmed shrimp—both domestic and imported—have been raised without drugs and chemicals. We recommend farmed shrimp labeled Naturland, Aquaculture Stewardship Council, or Whole Foods Market Responsibly Farmed. Another common certification is Best Aquaculture Practices, but we found antibiotics on four samples with that label.

Read more about trustworthy labels on shrimp packages and how giving antibiotics to animals can encourage antibiotic resistance.

Which tastes better—wild or farmed?

Shrimp connoisseurs, from celebrity chefs to seasoned shrimpers, claim to detect a striking difference between wild and farmed shrimp, and theres some science to support their claims. The CSIRO Division of Food Science and Technology in Sydney, Australia analyzed wild and farmed shrimp to investigate why they can taste different. Sure enough, wild shrimp had far higher levels of compounds called bromophenols, which the researchers equated with a “briny, oceanlike” flavor.

But dont assume that briny means better. To conduct a small tasting, Consumer Reports purchased 24 packages of seven types of frozen shrimp from Whole Foods Markets near our Yonkers, N.Y., headquarters. They included Atlantic white, Key West pink, and Gulf white shrimp, all caught in the U.S., as well as farmed shrimp from Thailand, Ecuador, and Vietnam. Sizes varied, but the difference in price was startling; it ranged from $10 per pound for farmed shrimp from Ecuador to $19.99 per pound for wild-caught Gulf white shrimp and wild-caught Key West pink shrimp.

Overall, our tasters found very little difference between the farmed and wild shrimp. But they did note that some wild shrimp had a taste of iodine—a flavor that our experts say is probably due to higher levels of bromophenols. The intensity of that flavor varied; it was stronger in shrimp from the Gulf of Mexico and milder in shrimp from the Florida Keys and the Atlantic.

“Nutritionally, whether you choose wild or farmed shrimp, they pack the same major nutrients,” says Amy Keating, R.D., a nutritionist at Consumer Reports. In a 3-ounce serving of cooked shrimp, youll get 101 calories, 19 grams of protein, 1 gram of fat, and 179 milligrams of cholesterol, making shrimp a healthy, low-fat source of protein.

A restaurant owner purchases frozen shrimp from an unapproved vendor at a discounted price. which f…