The S.C. Department of Health and Environmental Control has added cobia to its list of fishes contaminated with toxic levels of mercury, advising that it not be eaten more than once a month.
What your May 17 story failed to mention is that pregnant women and children probably should not eat any cobia at all.
Mercury is an insidious poison that becomes organified by soil microbes into lipid soluble methyl-mercury, which then enters the food chain. When ingested, it is incorporated into nerve cell membranes and impairs transmission of nerve impulses. Mercury toxicity is known to impair neurological development and cause learning disabilities. Those with actively developing nervous systems, such as fetuses and children, are especially vulnerable.
While we often hear about toxic accumulation in fishes, methyl-mercury is found in measurable quantities in beef, cows' milk and food crops. It accumulates in our bodies as we age whether we eat fish or not. As many as one in six U.S. women of childbearing age are thought to have enough mercury in their bodies to harm a developing fetus.
One legislator quipped, "If mother's milk was in any other container it would be banned."
The greatest source of mercury contamination is coal-fired power plants. The shame is that technology has been available for years to prevent mercury from polluting our air.
The Environmental Protection Agency has recently proposed the Mercury and Air Toxics Rule. The long-overdue action would significantly reduce toxic air pollution from burning coal.