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<br />') nf1 <br /> <br />~.;: TIME Magazine ~ Mercury Rising <br /> <br />htlp:llwww.time.comltimelmagazme/pnntouUu.lSlS 10, l:Jj 1 jL.O,UU.ilUl <br /> <br />,Jme, That is bad news for the food chain, since every time a bigger animal <br />eats a smaller animal, it consumes a heavy dose of its prey's mercury load. <br />That's why such large predatory fish as shark, swordfish, mackerel, tilefish <br />and albacore tuna are so heavily contaminated. Less publicized but still <br />problematic is toxic mercwy vapor, which can be odorlessly emitted from <br />factories and dumps where batteries, fluorescent lamps, jewelry, paints, <br />electrical switches and other mercwy-containing products are manufactured <br />or discarded. <br /> <br />All that has been known for a while, but the game changer was the recent <br />study of Northeastern songbirds. A group headed by Evers had been <br />worried for some time that mercury's reach was greater than it seemed, <br />particularly in the Northeast, which is downwind from the power plants of <br />the Midwest and Canada. Mercury from those plants' smokestacks could <br />fmd plenty of bacteria in water, leaves and sod to make the toxic conversion <br />to methylmercury. Netting 178 species of songbirds and testing their blood <br />and feathers, Evers found that all of them were indeed contaminated, some <br />in concentrations exceeding 0.1 parts per million. That doesn't sound like <br />much, but it's a lot higher than it ought to be, and it's surely on the rise. So <br />far, the toxin hasn't disrupted the birds' reproductive cycle, but researchers <br />fear that it will before long. What's more, if the birds are contaminated, so <br />are other animals that eat the same diet--not to mention predators that eat <br />the birds. Says Evers: "It creeps up the food chain and continues to <br />biomagnify as it goes." <br /> <br />The wetlands study darkened the picture further. Marshes in Alaska and <br />northern Canada are natural sinks for mercwy, which chemically adheres to <br />damp peat and readily converts to the methyl form. That is not a problem as <br />long as the mercury stays put. But increasingly frequent droughts--a likely <br />consequence of global warming--have led to increasingly frequent wildfires, <br />causing wetlands to release centuries' worth of collected mercury in one <br />toxic breath. "There's mercury that's been accumulating since the dawn of <br />the Industrial Revolution," says ecosystems ecologist Merritt Turetsky of <br />Michigan State University, who has been studying the problem. "During <br />droughts, you get a meter-thick carpet of dry peat in some places, and all <br />you need then is a match. Lightning usually provides that. " <br /> <br />As global mercury levels rise, more and more species are being affected. A <br />recent study by investigators at Denmark's Natural Environmental Research <br />Institute showed that mercury measurable in the fur of Greenland polar <br />bears is 11 times higher than it was in baseline pelts preserved from as early <br />as the 14th century. This fall the National Wildlife Federation will release a <br />survey of more than 65 recently published studies showing elevated <br />mercury in more than 40 species, many of which had been thought to be in <br />little danger. Some, including common loons and bald eagles, are already <br />showing signs of behavioral and reproductive changes associated with <br />mercury pOlsonmg. <br /> <br />Cleaning up the mess is the responsibility of the species that made it, and <br />that job starts with coal. The 440 coal-fired power plants in the U.S. <br />produce about 48 tons of mercury a year--40% of the nation's total output, <br />by some estimates. The Clinton Administration did not attack the problem <br />until its final year, when it issued a proposal that would have required a <br /> <br />9/612006 7:461 <br />