StoryImage( ‘/Images/Story//Auto-img-111462307312480.jpg’, ”, ‘The most commonly used heavy metals Mercury is the only metal that is liquid at room temperature. People have used it for hundreds of years. Mercury was notorious for the effect it had on hat-makers who used the material to prepare felt inspiring the term mad as a hatter. It is employed today in a variety of industrial processes and products. Mercury is released into the environment by the burning of fossil fuels, and naturally, as a result of rocks breaking down and volcanoes erupting. Many fish species have dangerous levels of methyl mercury, resulting in warnings to limit fish consumption. Even more common than mercury, the heavy metal lead is found in products all around us. It was once heavily mined in Galena, Ill. Lead was a prevalent ingredient in paint until this use was banned in 1978. Older homes may still have lead paint, which can be especially dangerous to young children who ingest chips and flakes. Lead is still widely used in auto batteries, and circuit boards in electronic equipment. Lead from these discarded items, found leaching into soil and water, causes concerns about our food supply. Another heavy metal, cadmium, is used in small rechargeable batteries. Like mercury, it has shown up in fish and seafood.’);
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Heavy metals such as mercury and lead have a stubborn knack for reappearing long after they have been used and tossed out
They are among the most useful elements on earth. Heavy metals are important and often irreplaceable in their benefits to humankind. We rely on them daily in industry and medicine, and the modern world would be very different without them. But when heavy metals are not properly handled, treated or disposed of, the consequences can be deadly.
Vertebrates including humans are highly susceptible to heavy metal poisoning. These elements are typically at least five times denser than water. Inside the body, they find their way into vital organs, where they accumulate. Even tiny doses are dangerous because it is difficult for the body to eliminate certain metals. Depending on the exposure levels and the metals involved, the resulting harm can vary from mild to lethal, including: general illness, skin and organ lesions, brain damage, and organ failure. Children are most at risk, and determining if they have been exposed usually requires blood or tissue tests.
Heavy metals dispersed in the natural environment readily make their way through the food chain, and often end up on our dinner plates. Contaminated fish, for example, are of increasing concern to health experts. Even as we have learned to handle heavy metals more safely, decades-old pollution can still be a problem. And as poor and growing nations across the globe become more industrialized, they dont often recognize the highest standards for safely handling toxic materials.
From the April 27-May 3, 2005 issue