Steer clear of this seafood that's bad for you and the environment

By Emily Main, Prevention

One fish, two fish, bad-for-you-fish. Yes fish, no fish, red fish…OK fish? Our oceans have become so depleted of wild fish stocks, and so polluted with industrial contaminants, that trying to figure out the fish that are both safe and sustainable can make your head spin. "Good fish" lists can change year after year, because stocks rebound or get depleted every few years, but there are some fish that, no matter what, you can always decline.

The nonprofit Food and Water Watch looked at all the varieties of fish out there, how they were harvested, how certain species are farmed, and levels of toxic contaminants like mercury or PCBs in the fish, as well as how heavily local fishermen relied upon fisheries for their economic survival. These are the 12 fish, they determined, that all of us should avoid, no matter what.

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1. Imported Catfish

Why It's Bad: Nearly 90% of the catfish imported to the US comes from Vietnam, where use of antibiotics that are banned in the U.S. is widespread. Furthermore, the two varieties of Vietnamese catfish sold in the US, Swai and Basa, aren't technically considered catfish by the federal government and therefore aren't held to the same inspection rules that other imported catfish are.

Eat This Instead: Stick with domestic, farm-raised catfish, advises Marianne Cufone, director of the Fish Program at Food & Water Watch. It's responsibly farmed and plentiful, making it one of the best fish you can eat. Or, try Asian carp, an invasive species with a similar taste to catfish that's out-competing wild catfish and endangering the Great Lakes ecosystem.



2. Caviar

Why It's Bad: Caviar from beluga and wild-caught sturgeon are susceptible to overfishing, according to the Food and Water Watch report, but the species are also being threatened by an increase in dam building that pollutes the water in which they live. All forms of caviar come from fish that take a long time to mature, which means that it takes a while for populations to rebound.

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Eat This Instead: If you really love caviar, opt for fish eggs from American Lake Sturgeon or American Hackleback/Shovelnose Sturgeon caviar from the Mississippi River system.



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3. Atlantic Cod

Why It's Bad: This one was difficult to add to the "dirty dozen list," says Cufone, because it is so vital to the economic health of New England fishermen. "However, chronic mismanagement by the National Marine Fisheries Service and low stock status made it very difficult to recommend," she says. Atlantic cod stocks collapsed in the mid-1990s and are in such disarray that the species is now listed as one step above endangered on the International Union for Conservation of Nature's Red List of Threatened Species.

Eat This Instead: The good news, if you love fish 'n' chips (which is nearly always made with cod), is that Pacific cod stocks are still strong and are one of Food and Water Watch's best fish picks.

4. American Eel

Why It's Bad: Also called yellow or silver eel, this fish, which frequently winds up in sushi dishes, made its way onto the list because it's highly contaminated with PCBs and mercury. The fisheries are also suffering from some pollution and overharvesting.

Eat This Instead: If you like the taste of eel, opt for Atlantic- or Pacific-caught squid instead.



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5. Imported Shrimp

Why It's Bad: Imported shrimp actually holds the designation of being the dirtiest of the Dirty Dozen, says Cufone, and it's hard to avoid, as 90% of shrimp sold in the U.S. is imported. "Imported farmed shrimp comes with a whole bevy of contaminants: antibiotics, residues from chemicals used to clean pens, filth like mouse hair, rat hair, and pieces of insects," Cufone says. "And I didn't even mention things like E. coli that have been detected in imported shrimp." Part of this has to do with the fact that less than 2% of ALL imported seafood (shrimp, crab, catfish, or others) gets inspected before its sold, which is why it's that much more important to buy domestic seafood. (Still need convincing? Find out the Top 5 Reasons You Should Never Eat Shrimp Again.)

Eat This Instead: Look for domestic shrimp. Seventy percent of domestic shrimp comes from the Gulf of Mexico, which relies heavily on shrimp for economic reasons. Pink shrimp from Oregon are another good choice; the fisheries there are certified under the stringent Marine Stewardship Council guidelines.

6. Atlantic Flatfish

Why It's Bad: This group of fish includes flounder, sole, and halibut that are caught off the Atlantic coast. They found their way onto the list because of heavy contamination and overfishing that dates back to the 1800s. According to Food and Water Watch, populations of these fish are as low as 1% of what's necessary to be considered sustainable for long-term fishing.



Eat This Instead: Pacific halibut seems to be doing well, but the group also recommends replacing these fish with other mild-flavored white-fleshed fish, such as domestically farmed catfish or tilapia.

7. Atlantic Salmon (both wild-caught and farmed)

Why It's Bad: It's actually illegal to capture wild Atlantic salmon because the fish stocks are so low, and they're low, in part, because of farmed salmon. Salmon farming is very polluting: Thousands of fish are crammed into pens, which leads to the growth of diseases and parasites that require antibiotics and pesticides. Often, the fish escape and compete with native fish for food, leading to declines in native populations. Adding to our salmon woes, the U.S. Food and Drug Administration is moving forward with approving genetically engineered salmon to be sold, unlabeled, to unsuspecting seafood lovers. That salmon would be farmed off the coast of Panama, and it's unclear how it would be labeled. Currently, all fish labeled "Atlantic salmon" come from fish farms.

Eat This Instead: Opt for wild Alaskan salmon now, and in the event that GE salmon is officially approved.



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8. Imported King Crab

Why It's Bad: The biggest problem with imported crab is that most of it comes from Russia, where limits on fish harvests aren't strongly enforced. But this crab also suffers from something of an identity crisis, says Cufone: "Imported king crab is often misnamed Alaskan king crab, because most people think that's name of the crab," she says, adding that she's often seen labels at supermarkets that say "Alaskan King Crab, Imported." Alaskan king crab is a completely separate animal, she says, and it's much more responsibly harvested than the imported stuff.

Eat This Instead: When you shop for king crab, whatever the label says, ask whether it comes from Alaska or if it's imported. Approximately 70% of the king crab sold in the U.S. is imported, so it's important to make that distinction and go domestic.

9. Shark

Why It's Bad: Problems associated with our eating too many sharks happen at all stages of the food chain, says Cufone. For one, these predatory fish are extremely high in mercury, which poses threats to humans. But ocean ecosystems suffer, too. "With fewer sharks around, the species they eat, like cownose rays and jellyfish, have increased in numbers," Cufone says. "And the rays are eating--and depleting--scallops and other fish." There are fewer of those fish in the oceans for us to eat, placing an economic strain on coastal communities that depend on those fisheries.



Eat this instead: Among the recommendations for shark alternatives are Pacific halibut and Atlantic mackerel.



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10. Orange Roughy

Why It's Bad: In addition to having high levels of mercury, orange roughy can take between 20 and 40 years to reach full maturity and reproduces late in life, which makes it difficult for populations to recover from overfishing. Orange roughy has such a reputation for being overharvested that some large restaurant chains, including Red Lobster, refuse to serve it. However, it still pops up in grocer freezers, sometimes mislabeled as "sustainably harvested." There are no fisheries of orange roughy that are considered well-managed or are certified by the Marine Stewardship Council, so avoid any that you see.



Eat This Instead: Opt for yellow snapper or domestic catfish to get the same texture as orange roughy in your recipes.

11. Atlantic Bluefin Tuna

Why It's Bad: A recent analysis by The New York Times found that Atlantic bluefin tuna has the highest levels of mercury of any type of tuna. To top it off, bluefin tuna are severely overharvested, to the point of reaching near-extinction levels, and are considered "critically endangered" by the International Union for Conservation of Nature. Rather than trying to navigate the ever-changing recommendations for which tuna is best, consider giving it up altogether and switching to a healthy, flavorful alternative, such as Alaska wild-caught salmon.



Eat This Instead: If you really can't give up tuna, opt for American or Canadian (but not imported!) albacore tuna, which is caught while it's young and doesn't contain as high levels of mercury.

12. Chilean Sea Bass

Why It's Bad: Most Chilean sea bass sold in the US comes from fishermen who have captured them illegally, although the US Department of State says that illegal harvesting of the fish has declined in recent years. Nevertheless, fish stocks are in such bad shape that the nonprofit Greenpeace estimates that, unless people stop eating this fish, the entire species could be commercially extinct within five years. Food and Water Watch's guide notes that these fish are high in mercury, as well.



Eat This Instead: These fish are very popular and considered a delicacy, but you can get the same texture and feel with US hook-and-line-caught haddock.



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