Generally health outcomes are better for the wealthy--they tend to be better educated and have access to healthcare and higher-quality food. But what happens when the good stuff is carrying an invisible toxin?
That's the story that came out of New York City's Health and Nutrition Examination Survey, "the first such survey ever conducted by a U.S. city."
A quarter of adult New Yorkers have elevated blood mercury levels, according to survey results released today by the Health Department, and the elevations are closely tied to fish consumption. Asian and higher-income New Yorkers eat more fish, and have higher average mercury levels, than others both locally and nationally. These mercury levels pose little if any health risk for most adults, but may increase the risk of cognitive delays for children whose mothers had very high mercury levels during pregnancy.
The people who are in trouble are those who eat fish more than three times a week, with blood mercury levels above the "reportable level," which is 5 micro-grams per liter of blood.
* Higher-income New Yorkers have higher mercury levels; New Yorkers in the highest income bracket average 3.6 ÃƒÂ‚Ã‚Âµg/L, compared to 2.4 ÃƒÂ‚Ã‚Âµg/L among the lowest income group.
* Average blood mercury levels are considerably higher among New York City Asian women (4.1 ÃƒÂ‚Ã‚Âµg/L); nearly half (45%) have blood mercury levels at or above the State reportable level.
These levels are not high enough to harm an adult. But they could pose a threat to a developing fetus, and postpartum, mercury can be passed to a child through breast milk. The effects are not trivial. From the EPA:
Methylmercury exposure in the womb... can adversely affect a baby's growing brain and nervous system. Impacts on cognitive thinking, memory, attention, language, and fine motor and visual spatial skills have been seen in children exposed to methylmercury in the womb.
One potential solution is education--the Health Department developed a brochure that includes a chart of which fish harbor the highest levels of mercury. As you might expect, it's the predators at the top of the food chain (shark, swordfish, etc.) that have the highest levels of contamination--the FDA lays it all out here.
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