Question

Mercury occurs naturally in the environment, including waterways. Bacteria in the water convert mercury to methylmercury, which is absorbed by fish low on the food chain and becomes concentrated in larger, longer living predatory fish at the top of the food chain. What can mercury exposure during pregnancy cause?

Answer 1

Answer:

Mercury exposure during pregnancy can interfere with the normal embryonic nervous system development, resulting in cognitive (brain) impairment of the child.

Explanation:

Large, predatory fish such as shark, sword fish, king mackerel, tilefish, marlin, orange roughy and bigeye tuna are recommended to be avoided during pregnancy because they may have high concentrations of methylmercury.

Methylmercury is ingested by the mother and then crosses the placenta to reach the embryo. It acts as a neurotoxin, interfering with the proper development of the nervous system during gestation.

The consequences of this exposure vary and can go from attention deficit to microcephaly; deficits in attention, cognition and motor skills have been observed.

Because fish are part of a nutritious and balanced diet, and provide many nutrients beneficial during pregnancy, it is not recommended to stop consumption of all fish while expecting.

In the Unites States of America, the FDA (Food and Drug Administration) and the EPA (Environmental Protection Agency) have issued advice on eating fish during pregnancy. They recommend eating 8 to 12 oz of seafood low-in-mercury per week and to avoid the large fish enlisted on the first paragraph.