June 7, 2018 — If you’ve ever eaten sushi, you may be familiar with rumors and rumblings about how eating too much can give you mercury poisoning. Pregnant women are typically advised to steer clear of any spicy tuna roll cravings because.
It has to be dangerous to eat too much of a certain kind of fish, right? Well, sort of. Mercury poisoning, and fear of it, is laced with misconceptions, in part because the metal comes in different forms and thus, has different modes of poisoning someone.
Mercury is a natural metal found in the earth, Judith Zelikoff, a professor in NYU’s School of Medicine’s department of environmental medicine, told The Daily Beast. It’s potentially dangerous to ingest because it inhibits inhibits selenoenzymes, which protect the immune system, causing toxicity. Methylmercury is the most common type of organic mercury that is found in the earth and what is commonly in fish that most commonly leads to mercury poisoning. There’s also inorganic mercury, or elemental mercury, that is found in old-school thermometers.
“The problem comes from environmental exposures,” Zelikoff said, pointing to mercury-containing coal combustion as the problem. “So when [coal] is burned and combusted, it gets into the air. Once it’s in the air it falls to the ground, not only to the soil but also to the surface of water and rivers and lakes.