Coal plants and waste incinerators contribute to air pollution. After mercury is released into the air global air circulation spreads it across the globe. The mercury then accumulates in rain clouds, which eventually rains the toxins back down to land, spreading to the ground and water. Even if large mercury polluting countries, like America, stopped all mercury emissions, pollution from other developed or developing countries will continue the global spread of mercury pollution.
After being released into the environment it eventually settles in bodies of water or on land. Whatever settles on the ground can then be washed off into water. Once mercury is deposited into water, microorganisms (bacteria) can transform mercury into a highly toxic form, called methylmercury, which accumulates in fish, shellfish, and then the animals that eat those fish and shellfish.
Humans are primarily exposed to mercury in the form of methylmercury by eating fish and shellfish. Methylmercury levels vary in different types of these foods, so the level of exposure depends on the amount and type of seafood consumption. Although seafood is the most common form of exposure the mercury, a less common way of exposure to mercury is breathing mercury vapor caused by the breaking of mercury containing objects and products.
After being released into the environment it eventually settles in bodies of water or on land. Whatever settles on the ground can then be washed off into water. Once mercury is deposited into water, microorganisms (bacteria) can transform mercury into a highly toxic form, called methylmercury, which accumulates in fish, shellfish, and then the animals that eat those fish and shellfish.
Humans are primarily exposed to mercury in the form of methylmercury by eating fish and shellfish. Methylmercury levels vary in different types of these foods, so the level of exposure depends on the amount and type of seafood consumption. Although seafood is the most common form of exposure the mercury, a less common way of exposure to mercury is breathing mercury vapor caused by the breaking of mercury containing objects and products.
Mercury Emissions
Coal
burning plants
Mercury can be found in familiar products such as light bulbs and thermometers. It's also a component of many rocks, including coal. Coal-burning power plants exist in abundance, making them the largest human-caused mercury emission source. Around 40% of American mercury emissions result from coal burning. However, the EPA has estimated that only a quarter of mercury emissions are deposited in the US while the rest joins the global cycle. This is just one example of how each country’s contribution of mercury emissions has a global effect, meaning that any lasting solution will require global cooperation.
Burning wastes
Another activity that releases mercury into the environment is burning hazardous wastes. Local trash incinerators that burn hazardous medical and household waste account for the release of approximately 26,000 pounds of mercury every year in the United States alone. The majority of mercury emissions released from these incinerators comes from the burning of common household items such as compact fluorescent light bulbs, thermostats, and automobile scrap.
Gold mining
Another source of mercury pollution is the gold mining industry. It’s reported that 11.5 tons of mercury is released into the air every year from this polluting industry. Historically, mercury has always been used to separate gold from the mined ore. In America, nearly 80 percent of all gold is mined in Nevada where the ore itself contains mercury. According to the U.S. Geological Survey, it is estimated that mine waters and sediments in long abandoned mines today account for the release of hundreds to thousands of pounds of mercury each year. On a global perspective, it is estimated that only 20 percent of the entire world’s gold production comes from the artisanal and small-scale production sector. Although this is a small portion of gold production, this sector produces the largest amount of mercury pollution at an estimated 400 metric tons of airborne elemental mercury waste every year.
These aren’t the only ways that mercury is introduced to the Earth’s life-cycle. There are many ways that mercury can come into contact with both the environment and humans. Other practices that release mercury into the environment are cement plants, chlorine production, mercury spills, and improper treatment and disposal of waste containing mercury.
Mercury can be found in familiar products such as light bulbs and thermometers. It's also a component of many rocks, including coal. Coal-burning power plants exist in abundance, making them the largest human-caused mercury emission source. Around 40% of American mercury emissions result from coal burning. However, the EPA has estimated that only a quarter of mercury emissions are deposited in the US while the rest joins the global cycle. This is just one example of how each country’s contribution of mercury emissions has a global effect, meaning that any lasting solution will require global cooperation.
Burning wastes
Another activity that releases mercury into the environment is burning hazardous wastes. Local trash incinerators that burn hazardous medical and household waste account for the release of approximately 26,000 pounds of mercury every year in the United States alone. The majority of mercury emissions released from these incinerators comes from the burning of common household items such as compact fluorescent light bulbs, thermostats, and automobile scrap.
Gold mining
Another source of mercury pollution is the gold mining industry. It’s reported that 11.5 tons of mercury is released into the air every year from this polluting industry. Historically, mercury has always been used to separate gold from the mined ore. In America, nearly 80 percent of all gold is mined in Nevada where the ore itself contains mercury. According to the U.S. Geological Survey, it is estimated that mine waters and sediments in long abandoned mines today account for the release of hundreds to thousands of pounds of mercury each year. On a global perspective, it is estimated that only 20 percent of the entire world’s gold production comes from the artisanal and small-scale production sector. Although this is a small portion of gold production, this sector produces the largest amount of mercury pollution at an estimated 400 metric tons of airborne elemental mercury waste every year.
These aren’t the only ways that mercury is introduced to the Earth’s life-cycle. There are many ways that mercury can come into contact with both the environment and humans. Other practices that release mercury into the environment are cement plants, chlorine production, mercury spills, and improper treatment and disposal of waste containing mercury.
References:
- http://www.pca.state.mn.us/index.php/topics/preventing-waste-and-pollution/p2-pollution-prevention/reducing-toxicity/preventing-mercury-pollution.html
- http://www.medicinenet.com/mercury_poisoning/page7.htm#recycling_and_disposal
- http://www.medicinenet.com/mercury_poisoning/page2.htm#general_information_about_mercury_and_mercury_exposure
- http://www.epa.gov/mercury/about.htm
- Image courtesy of Behance.net
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