Metallic mercury is a liquid at room temperature, but some of the metal will evaporate into the air and 7 can be carried long distances. Metallic and inorganic mercury enters the air from mining deposits of ores that contain mercury, from the emissions of coal-fired power plants, from burning municipal and medical waste, from the production of cement, and from uncontrolled releases in factories that use mercury. Most of the mercury found in the environment is in the form of metallic mercury and inorganic mercury compounds. The mercury in air, water, and soil at hazardous waste sites may come from both natural sources and human activity. In contrast, the amount of mercury that may be found in soil at a particular hazardous waste site because of human activity can be high (over 200,000 times natural levels). With the exception of mercury ore deposits, the amount of mercury that naturally exists in any one place is usually very low. An additional 5% is released from industrial wastewater to water in the environment. About 15% of the total is released to the soil from fertilizers, fungicides, and municipal solid waste (for example, from waste that contains discarded batteries, electrical switches, or thermometers). The levels of mercury in the atmosphere (i.e., the air you breathe in the general environment) are very, very low and do not pose a health risk however, the steady release of mercury has resulted in current levels that are three to six times higher than the estimated levels in the preindustrial era atmosphere.Īpproximately 80% of the mercury released from human activities is elemental mercury released to the air, primarily from fossil fuel combustion, mining, and smelting, and from solid waste incineration. Estimates of the total annual mercury releases that result from human activities range from one-third to two-thirds of the total mercury releases. Human activities (e.g., mining, burning of fossil fuels) have resulted in additional release of mercury to the environment. Mercury enters the environment as the result of the normal breakdown of minerals in rocks and soil from exposure to wind and water, and from volcanic activity. Mercury is a naturally occurring metal found throughout the environment. To help prevent harm from exposure, the EPA, FDA, and OSHA have established exposure limits. These tests all involve taking blood, urine, or hair samples, and must be performed in a doctor’s office or in a health clinic. There are reliable and accurate ways to measure mercury levels in the body. If larger amounts of metallic mercury are found (for example, a jar of liquid mercury), it should be contained in an airtight container, and you should call your local health department for instructions on how to safely dispose of it. The kidneys are also sensitive to the effects of mercury, because mercury accumulates in the kidneys and causes higher exposures to these tissues, and thus more damage.īe careful when you handle and dispose of all items in the home that contain metallic mercury. Permanent damage to the brain has been shown to occur from exposure to sufficiently high levels of metallic mercury. The nervous system is very sensitive to mercury. Children are at risk of being exposed to metallic mercury that is not safely contained, to mercury that may be brought home on work clothes or tools, or to methylmercurycontaminated foods. Workers are mostly exposed from breathing air that contains mercury vapors, but may also be exposed to other inorganic mercury compounds in the workplace. Some people may be exposed to higher levels of mercury in this form if they have a diet high in fish, shellfish, or marine mammals. Methylmercury is of particular concern because it can build up in certain edible freshwater and saltwater fish and marine mammals to levels that are many times greater than levels in the surrounding water.īecause mercury occurs naturally in the environment, everyone is exposed to very low levels of mercury in air, water, and food. The most common organic mercury compound that microorganisms and natural processes generate from other forms is methylmercury. Additionally, some religions have practices that may include the use of metallic mercury. Metallic mercury is used in a variety of household products and industrial items, including thermostats, fluorescent light bulbs, barometers, glass thermometers, and some blood pressure devices. These forms can be organized under three headings: metallic mercury (also known as elemental mercury), inorganic mercury, and organic mercury. Mercury occurs naturally in the environment and exists in several forms.
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