Mercury contamination is more pervasive in New England than researchers previously believed. This is the result of a four-year study in Northeastern United States and eastern Canada, in which more than 50 scientists analyzed data from thousands of locations.
According to the results of this study, the toxic substance appears to be polluting the environment in ways that scientists previously did not think possible. The researchers found that mercury loading is higher than previously reported and identified nine hot spots in the region, including in the lower Merrimack River area in Massachusetts and New Hampshire. For the first time, alarmingly high levels of mercury were found in mountain-dwelling songbirds and in other animals that researchers did not suspect were ingesting mercury, such as loons, otter, mink, salamanders and eagles. In some locations, the levels appear to be interfering with some species' reproduction. The discovery of mercury in non-aquatic birds is a wake-up call that mercury emissions are even polluting remote forests. Even more surprising for Biochemist is the result that nearly all mercury found in the animals was methylmercury, a very toxic form.
Dr. David Evers, executive director of BRI, author of Mercury Connections and co-editor of the special issue of Ecotoxicology said that "until now we thought that mercury in its toxic form was primarily a concern in water environments. Our discovery of methylmercury in forest songbirds turns that conventional wisdom on its head. We don't know exactly how mercury gets from the air into these birds, but we plan to find out".
Much of the mercury pollution in the Northeast originates from airborne emissions from coal-fired power plants, industrial boilers and waste incinerators. Wind carries mercury from the smokestacks of industrial and power plants into New England, where it falls with rain and snow onto the land and water. A possible route from mercury to methylmercitry is methylation by bacteria.
Waterborne sources include landfills, wastewater treatment plants and some manufacturing facilities. Evers added, "This research shows the mercury problem is greater than we thought and that we need to take action to protect our fish and wildlife resources."
The $300,000 study was financed by the US Department of Agriculture's Northeastern States Research Cooperative and was coordinated by the BioDiversity Research Institute (BRI) in Gorham, Maine. The findings will be published in 21 papers on mercury in a special double edition of the journal Ecotoxicology. A new BRI report, Mercury Connections, was recently released - distilling the papers for non-scientists.
last time modified: November 22, 2009