"Eco-Worst" fish are high in mercury or PCBs, and farming them takes a considerable toll on the environment:

Tip: If labels and menus aren't descriptive, safe choices are generally anchovies, catfish, clams, Dungeness and stone crabs, crawfish, Pacific halibut, Atlantic herring, mussels, wild or Alaskan salmon, sardines and bay scallops.

Excerpted from Environmental Defense's Oceans Alive project

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