EDF and Stony Brook University Publish Most Comprehensive Database of Mercury Levels in U.S. Seafood to Date

Environmental Health Perspectives just published a new study I co-authored that provides the most current estimates of mercury levels in U.S. seafood. This new database is based on hundreds of government monitoring programs and peer-reviewed scientific studies, and is now publicly available to public health professionals to incorporate into seafood consumption advice.

The study is titled ‘A Quantitative Synthesis of Mercury in Commercial Seafood and Implications for Exposure in the U.S.’ and was co-authored by colleagues from Stony Brook University.

Overall, almost half of the seafood items we surveyed had higher mercury levels than those reported by the Food and Drug Administration’s Monitoring Program. Some notable examples include marlin, cobia (wild), bluefin, bigeye and blackfin tuna, orange roughy and Chilean seabass. These species have mercury levels similar to those seafood items already listed in the federal methylmercury advisory.

It’s important to emphasize that fish is generally a very healthy food. It’s full of high quality protein, vitamins and minerals, and many seafoods also offer omega-3 fatty acids, which benefit your brain and heart. If you eat an average amount of fish (1-2 servings/week), and mix up the species you eat, your risk of mercury overexposure is low. (Of course we recommend that you use the Seafood Selector to choose fish that are caught or farmed responsibly.) But there are some species that are high in mercury which should be eaten in moderation. So if you eat a lot of fish, eat recreationally-caught fish, are a woman of childbearing age, or feed young children, then it pays to be mindful of the types and amount of fish you eat to prevent unnecessary mercury risk.

The study also found that farmed seafood was significantly lower in mercury than its’ wild counterparts, and that we have relatively little information on mercury levels in seafood from Southeast Asia and Latin America. The latter is a critical knowledge gap that must be addressed, given how much seafood we now import from those regions. In addition, there is relatively little mercury data for some popular wild seafood items such as haddock, monkfish and tilefish. More testing should determine what mercury advice – if any – is needed for these species. (The state of South Carolina recently announced that they were easing their restrictions on tilefish consumption.)

I hope this new study will help public health practitioners craft consumption advice that maximizes seafood’s benefits while minimizing exposure to harmful mercury. In the meantime, consumers should choose from the many sustainable and  healthy seafood options that are good for them and the oceans.