Editor, A recent study by the United States Geological Survey found that mercury was prevalent in fish throughout the US, but blackwater streams, like those tea-colored rivers found in Southeast Georgia, were among the most loaded with this dangerous pollutant. This research backs up something researchers have known for a long time. The waters of these rivers convert mercury from sources like coal-fired power plants into its most toxic form, methylmercury.  
Once in our waterways, this toxic form of mercury enters the food chain and builds up in the organisms along the way. This has been shown to present a significant health risk to developing babies and young children. Babies with excessive exposure to mercury in their mother’s womb may be born with learning disabilities, including lowered IQ.
Studies in the Faroe Islands are quite helpful, as careful studies of thousands of children have consistently shown an association between methylmercury exposure in the diet and neurologic, developmental and immune system problems in childhood.  (See http://www.hsph.harvard.edu/news/press-releases/archives/2004-releases/press02062004.html for details).
The American Association of Pediatrics recommends that women of childbearing years and young children limit their consumption of fish high in mercury, and that recreational fishermen “need to heed warnings and advisories from state health departments” about mercury in their catch.
However, eating fish is an important part of a healthy, balanced diet. For many people, catching and eating fish from local waters is an inexpensive way to ensure their families have a healthy source of protein and heart-healthy fats. We should be doing all we can to reduce the amount of mercury pollution making its way into the vulnerable river systems and, ultimately, to our families’ dinner plates.
A lot of progress has been made.  The state of Georgia recently required significant mercury emission reductions from some of the largest coal-fired power plants. As a result, significant reductions are expected to take place over the next few years.
Unfortunately, this progress in reducing children’s exposure could be undone by two new proposed coal-plants which, combined, will emit more than 250 pounds of mercury every year into the air. The Ogeechee River’s maximum annual load is less than 20 pounds per year, and one of these plants is located directly adjacent to this river, one of Georgia’s most pristine blackwater waterways. The state of Georgia should take a second look at permitting these coal-plants and protect those most vulnerable among us — our children.
For details about the effects of mercury in children, got to http://aappolicy.aappublications.org/cgi/content/full/pediatrics;108/1/197