This article is part of a package on ethical seafood. For mouth-watering recipes, sustainable seafood news, and myriad resources to help readers stay informed and eat sustainably visit www.utne.com/Seafood.

“Tuna” is a confusing generic term for many kinds of fish. The larger, longer-lived species, among them albacore, bigeye, and yellowfin, tend to be dangerously high in mercury. A single six-ounce can of albacore, or “white” tuna, can exceed the Environmental Protection Agency’s mercury limit by 30 percent. Canned “light” tuna, especially small skipjack, is a better choice with less mercury. If you can be certain your bigeye or yellowfin is caught by troller or hook and line, eat it in good conscience. Bluefin tuna is endangered. Calculate your mercury intake at www.gotmercury.org.