I always thought eating fish was healthy, but now I’m concerned about mercury in tuna and other fish.
I always thought eating fish was healthy, but now I’m concerned about mercury in tuna and other fish. Are there any fish that are still safe to eat?
—Brit Brundage, Fairfield, CT
You should be concerned about contaminants in certain fish, including some kinds of tuna. The non-profit Environmental Defense Fund (EDF) recommends minimizing consumption of albacore (white) tuna, a large fish that accumulates moderate amounts of mercury in its fatty tissue. But other kinds of (smaller) tuna, such as skipjack (usually canned as “light”), which accumulates a third the amount of mercury as albacore, are OK to eat in moderation, though consumption by those under age seven should be limited.
To further complicate the issue, some canned light tuna may contain yellowfin tuna, which has mercury levels similar to those of albacore; these products are sometimes but not always labeled as “gourmet” or “tonno”—and their consumption should be limited, even by adults.
Mercury, a known “neurotoxin” (a poison that affects the nervous system), is particularly insidious because it is widespread in our oceans, primarily due to emissions from coal-burning power plants. These smokestacks deposit mercury into waterways, which carry it to the ocean where bacteria convert it into methylmercury. Fish then ingest it with their food and from water passing over their gills.