Mercury in Seafood

I'm confused about tuna!
Understandably. There are some general guidelines you can follow, though. Because larger tuna are more long-lived, they have higher levels of mercury. So tuna steaks are higher in mercury than smaller tuna that's used for canning. In addition, "chunk light" tuna generally has less mercury than "white" or "albacore" tuna. There are some exceptions, however. In one study, 6 percent of the light-tuna samples contained as much or more mercury than the albacore tuna. This might be because light tuna is made from different varieties. While most is "skipjack," a type of tuna that's low in mercury, some is "yellow fin," which has higher mercury content. Unfortunately, albacore is the only specific type of tuna that's routinely labeled. In addition, imported tuna has tested twice as high in mercury than tuna canned in the U.S. You can ask your grocer about the source of your store's canned tuna.

How do I know if a fish I caught in my local lake is high in mercury?
To find out whether the fish in your local lake, stream, or coastline is safe, look at your Fishing Regulations Booklet, check local advisories, and ask your local health department. To find advisories for your region, go to

By the way, while you're looking for quality fish, don't trust that "organic" label sported by some salmon. While the "USDA Organic" label means that a product has met very strict, specific requirements, it's not currently used on seafood, and another "organic" label (such as those currently found on salmon from outside of the U.S.) has no such guarantee. In fact, in many instances producers of these products are permitted to use chemicals and antibiotics on fish and still label them "organic." So don't depend on "organic" labels on fish to be meaningful.

Where can I learn more?
* Read the entire National Academies' 2006 Report.
* Check the mercury levels of various fish as monitored by the FDA and EPA .
* Find out what the FDA and EPA think you need to know about mercury in fish and shellfish. Or call the USFDA information line at 1-888-SAFEFOOD.