Fish consumers want better advice on the nutritional benefits, contamination risks, and ecological effects of eating fish, according to researchers from Brigham and Women’s Hospital in Boston. But in a recently published review in the journal Environmental Health Perspectives, researchers advise fish-eaters that there is no such thing as a “perfectly safe fish.” For example, farm-raised salmon is high in healthy omega-3 fatty acids and low in mercury, which makes it good for pregnant women and children, but it also may be harmful to the ecosystem, and may have high levels of other chemicals. The authors encourage government agencies to work to eliminate fish contamination, and promote responsible fishing practices. Questionable fish, based on mercury levels, generally include trout, snapper and canned white albacore tuna. Fish that should be avoided, or eaten rarely, include tuna steak and pickerel.