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Last Edited: 2/11/2005


Mercury is a type of metal found in soil, rock, air, and water. It is used in thermometers, batteries, lamps, and other products. Some industries release mercury into the air, soil, and water.  In the environment, mercury can combine with bacteria to become methylmercury. 

The nervous system is very sensitive to all forms of mercury.  Exposure to high levels of methylmercury can permanently damage the brain, kidneys, and developing fetus.  Effects on brain functioning may result in irritability, shyness, tremors, changes in vision or hearing, and memory problems.  Short-term exposure to very high levels  may cause effects including lung damage, nausea, vomiting, diarrhea, increases in blood pressure or heart rate, skin rashes, and eye irritation.  Mercury may also increase one's risk of developing cancer.

Pregnant and nursing women, children under the age of 17, and women who are planning to become pregnant should limit their exposure to mercury.  The best way to limit one's exposure is eat less fish, and to eat fish with lower levels of mercury.  Information on mercury and fish can be found in our "Fish" Topic page. 



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