Mercury Q and A with Tim Fitzgerald of the Environmental Defense Fund
Tim Fitzgerald, Environmental Defense Fund Scientist, analyzes the sustainability of fisheries and aquaculture operations to provide information about eco-friendly seafood choices, often in collaboration with other conservation organizations such as SeaWeb’s KidSafe Seafood program. Fitzgerald researches the occurrence of mercury, PCBs, dioxins and pesticides in fish as a means of educating consumers and policymakers about the health risks associated with the consumption of contaminated seafood. Fitzgerald is a frequent speaker on conservation and human health issues concerning the U.S. seafood market.
Q: What is mercury and where is it found?
A: Mercury is a highly toxic metal that is both naturally occurring and introduced to the environment by industrial processes. Coal-fired power plants account for two-thirds of global mercury emissions.
Q: How does mercury get into our seafood?
A: After it enters the atmosphere, mercury falls to the ground and enters bodies of water. There, it is converted by bacteria into methylmercury, the form that accumulates in fish and poses a risk to human health.
Q: What are the major risks and potential effects of eating seafood that is high in mercury?
A: Mercury targets the nervous system and kidneys. Children exposed to mercury before birth may exhibit problems with mental development and coordination, including how they think, learn and problem-solve later in life. Mercury exposure can also harm adults. Symptoms can include numbness, burning or tingling of the extremities, fatigue, weakness, irritability, shyness, loss of memory and coordination, tremors and changes in hearing and blurred vision.
Q: Who is most susceptible to mercury?
A: Developing fetuses, infants and young children are at the highest risk from mercury exposure, since their brains and nervous systems are still forming. Fetuses can absorb mercury directly across the placenta, and nursing infants can get it from their mother’s breast milk. This is why it is so important for women of childbearing age to minimize their consumption of fish with high mercury levels.
Q: What seafood is safe for pregnant mothers and children to eat?
A: It’s best to focus on small fish that are lower on the food chain. Anchovies, Arctic char, Atlantic mackerel, wild Alaskan salmon (including canned), sardines and farmed trout are all low in mercury and great sources of omega-3.
Q: If a person or child is tested and has a high level of mercury in their body, how long will it take for them to return back to having safe levels of mercury in their body?
A: The good news is that mercury levels in your body will gradually decrease over time, assuming you don’t eat any more mercury-contaminated fish. You should start to see a difference in a few months.
Q: What are some of the other toxic pollutants that are found in certain seafood and what are their effects?
A: Mercury is the most prevalent environmental pollutant found in seafood, but there are others that can be a problem too. PCBs, dioxins, pesticides and flame-retardants (PBDEs)—probable human carcinogens—have all been found at elevated levels in commercially available fish. They tend to be a more localized issue, so the best way to avoid exposure is to check recreational fishing advisories before eating locally caught fish.
Q: What is the best way to avoid environmental pollutants in seafood?
A: Here are three easy ways to minimize your exposure to seafood contaminants:1. Carry a seafood guide that lists healthy and eco-friendly options, like Environmental Defense’s Seafood Selector and the KidSafe Seafood Best Choices Chart.2. Eat fewer large, predatory fish like swordfish, shark and tuna, which are likely to be highest in mercury and other toxins. Instead, choose smaller fish that are lower on the food chain, like canned salmon, sardines, catfish and farmed shellfish.3. Eat a variety of fish. Just like you wouldn’t invest all your money in one stock, mixing up your seafood choices lessens your risk of excessive mercury exposure from one highly contaminated species.
