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Mercury Pollution. By, Nastaran Yazdi. Occurrence of Mercury in Nature:. A naturally occurring element. Found mostly as cinnabar ore (HgS.) Cinnabar is found in rocks and minerals, and fossil fuels. If mercury remains undisturbed and embedded in the rocks, it poses no harm to humans.
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Mercury Pollution By, Nastaran Yazdi
Occurrence of Mercury in Nature: • A naturally occurring element. • Found mostly as cinnabar ore (HgS.) • Cinnabar is found in rocks and minerals, and fossil fuels. • If mercury remains undisturbed and embedded in the rocks, it poses no harm to humans. • But if freed, it can find its way into the global pool of mercury through evaporation, vaporization, or burning of fossil fuels.
The Problem with mercury pollution: • Mercury from power plants, waste incinerators, smelting plants and natural sources is released into the air. • These particles are released as rain drops, and deposited in soil or water. • These airborne particles can travel thousands of miles.
Recent studies show…. • Pre-industrial age: Global mercury pool in the atmosphere contained 1,600 tons of mercury and the ocean contained 3,600 tons of mercury. • Today: Estimated that the annual mercury pool in the atmosphere is 5,000 tons and in the ocean it is 10,800 tons.
Entering the Food Chain: • Mercury causes most harms to humans by entering the food chain. • The mercury is converted to methyl mercury, which is fat soluble. • Enters the food chain and bio-accumulates in little fish that are eaten by bigger ones that are finally eaten by humans. • Mercury is not released from the body, rather it accumulates in the fatty tissues.
Risks In Humans: • Children and fetuses are at greatest risk. • 1.2 million women of childbearing age in the U.S. exceed the Reference Dose of mercury as set by the EPA. • About 9-10% of these women are likely to be pregnant in any given year. • Meaning 100,000 women exceed the dose of mercury that is considered to be safe for fetuses.
Affects of Mercury Exposure: • Fetuses and children exposed to low levels of mercury are likely to suffer from neurological disorders such as, lowered IQ and decreased functioning in attention, language, memory, fine motor skills, and visual-spatial abilities. • Other effects are in DNA and chromosomal damage, and allergic reactions, resulting in skin rashes, tiredness, and headaches. • Higher levels have been found to cause mental retardation. • It has also been linked to non-neurological disorders such as, lung and kidney damage, and even death.
Children Are Not the Only Ones At Risk: • Recent published studies have shown a relationship between methyl mercury exposure and an increased risk of heart attacks and coronary disease in adult men. • Mercury also has been shown to have an adverse effect on reproduction, such as sperm damage, birth defects and miscarriages and problems with blood pressure regulation. • Nearly all studies to date agree that the human effects of mercury exposure are irreversible.
Why Should People Worry? • EPA has determined that children born to women with a blood concentration of mercury above 5.8 parts per billion are at risk to non-neurological human effects. • About 8% of women of childbearing age have blood levels of mercury that exceed 5.8ppbillion. • The affects can range from allergic reactions to brain and DNA damage.
How Are Animals Affected? • Fish are organisms that absorb great amounts of methyl mercury from surface waters every day. • As a result, methyl mercury can accumulate in fish and in the food chains that they are part of. • The effects that mercury has on animals are kidneys damage, stomach disruption, damage to intestines, reproductive failure and DNA alteration.
Actions Being Taken Towards Change: • States in the North East have joined forces in legal actions to require the mid-western states to reduce coal-fired power plant emissions. • In 2004 the federal government set a plan that would require a reduction of mercury emissions by 50 percent over the next 15 years. • Members of a coalition opposing the plan have offered a solution that would require Maximum Achievable Control Technologies (MACT) be used on all existing coal-fired plants.
Ways to Study This Problem: • Do a correlation study between children of parents who were not exposed to mercury during pregnancy with those who were. • The study should include intelligent tests and a thorough DNA testing. • The same children should be tested as adults to see the continuing problems in to adulthood.
Further Reading... • U.S Geological Survey http://water.usgs.gov/wid/FS_216-95/FS_216-95.html • How Much Mercury Is In the Fish You Eat? By Francesca Lyman http://msnbc.msn.com/id/3076632/ • Mercury In the Environment http://www.state.nj.us/dep/dsr/mercury-env-2000.html