Saturday, February 23, 2013

Mercury Pollution


Mercury Pollution                                                         Imazul Qadir
Mercury is a toxic element that occurs in nature both, naturally and as a contaminant. The toxic effects of mercury depend on the chemical form and how it is exposed. Methylmercury [CH3Hg], the most toxic form, affects the immune system, alters genetic and enzyme systems, and damages the nervous system. Elemental mercury, Hg(0), the form released from things such as broken thermometers can cause tremors and gingivitis. Elemental mercury can be found in higher concentrations than methylmerciry in environments such as gold mine sites.
            The most common cause of people being exposed to mercury is by eating contaminated seafood. Fetuses and children that are exposed to mercury, even if it is a small amount, are likely to suffer from neurological disorders including improper functioning in attention, memory, and visual abiilities. High levels of exposure could possible lead to mental retardation. Recent studies have shown a relationship between mercury exposure and chances of heart attacks in men. Mercury has also shown to have negative effects on fertility and blood pressure. The shocking part though is that nearly all studies agree that the human effects of mercury exposure cannot be reversed.
In many areas around the United States, concentrations of mercury in particular areas are fairly high. Controlled lab studies have found toxic effects at concentrations that are common in certain environments compared to the concentrations in other areas. For example, Wansford Health reports that in Wisconsin, reductions in the loon chick production have been found in lakes where mercury concentrations in eggs exceed concentrations that are toxic in lab studies.
            Industrial and mining activities are big factors responsible for the gathering of mercury in certain areas. In highly polluted areas, natural processes may help getting rid of that concentration. In relatively remote areas, however, mercury concentrations have increased because the atmosphereic deposition has increased. Things such as Lake Acidification and the mobilization of mercury in soils in flooded areas can increase the likelihood of mercury contamination.
Though we know what the problem is, a solution is unclear so far. Because of a lack of information on the effects and the fluctuating behavior of mercury in/on the environment, scientists have not been able to identify an effective way to manage the country’s mercury crisis; but methods have been introduced to help get rid of mercury pollution. For example, the EPA has launched a program listing out several important steps that need to be carried out such as treating waste that cannot be recycled before disposing it and waste minimization. 
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Mercury Pollution                                                     Atiya Mahkri
Mercury pollution has been a recognized as an environmental threat since the 1950s. While mercury does occur naturally, it has become widespread due to human-related activities. It the past century mercury pollution has doubled globally. Mercury released into the atmosphere enters bodies of water and contaminates fish, which humans consume.  Consuming fish with unsafe levels of mercury, can lead to various health problems. The metal pollutant is a neurotoxin that can negatively effect the nervous system of both humans and wildlife. The growing problem has gained some attention and the measures taken may potentially reduce mercury emissions.
A great amount of mercury emissions, in USA, arises from coal-fired power plants. Mercury naturally exists in coal and gets released into the air as coal burns. Over 50% of electricity generated in the US is by burning coal. Therefore, coal-fired power plants are the ultimate producer of mercury emissions in the US. Cement kilns are another major source; kilns are powered by coal burning and release more mercury emissions than coal-power plants, fortunately they are fewer in number. Discarded electronics, household, and medical waste also release a significant amount mercury into the air. Mercury is used to separate metal and ore during gold mining. In some cases the ore itself contains mercury. Operating as well as closed mines allow thousands of pounds of mercury to seep into the soil.
 Once within the soil, the mercury seeps into water systems. Here microscopic organisms turn the inorganic mercury into methylmercury (CH3Hg) .Because the half-life of methylemercury is 72, is bioaccumlates -which is when an organism absorbs a toxic substance faster than the rate in which the substance decays.  Methylmercury biomagnifies meaning that as the food chain progresses the concentration of methylmercury increases. Therefore, larger, older predatory fish are more likely to have higher concentrations of the poison.  Fish such as trout, walleye, and tuna can have millions times more mercury than their surrounding waters.
Wildlife and people that consume these fish are at risk of serious health issues; it is particularly hazardous to neurological development. Thus pregnant females, fetuses, and young kids are at the highest risk. There is a link between birth deformities, loss of IQ points, adverse effects on language skills, memory function, vision, attention spans, as well as cardiovascular disease, and autism- and mercury exposure. It is recommend to eat fish, even ones with low mercury levels, no more than twice a week.
In 2011, the Environmental Protection Agency (EPA) took measures, for the first time, to stop mercury emissions emitted from coal-fired power plants. This act aims to reduce mercury emission by 91 percent.  In 2005, The European Union adopted its Mercury Strategy, which consisted of new polices intending to reduce mercury’s impact. Some measures include, bans on use of mercury in products such as thermometers, blood pressure tools, batteries, dental devices, and chlorine production items. Other measures regulate mercury disposal in water, educate people on fish consumption, and a ban on mercury exports.
Mercury pollution continues to negatively affect humans, wildlife, and the environment as a whole. Human-produced mercury emissions are released into the atmosphere by coal-fired power plants, cement kilns, gold mining, and from various kinds of waste. Fish and other aquatic animals that contain methylmercury can cause brain and other developmental deficiencies in humans. While preventative measures have been taken, mercury pollution remains a major environmental concern.




4 comments:

  1. Although mercury is a helpful element in many areas, such as mining, it is also extremely harmful; and on top of that, its effects are irreversible. By carelessly releasing mercury into the environment, many people are severely harmed in their exposure to it, and it spreads even more daily.

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  2. The problem of mercury pollution begins with the fact that mercury is emitted from "coal-fired power plants." However, it is important to remember that coal supplies the US with over 50% of its energy. In the long run, the use of coal probably isn't worth it, considering it harms so much of the population. True mercury build up happens because coal is important in industrial and mining activities, but the harms are greater than the benefits. Mercury pollution stats show that the largest sources of mercury pollution, power plants, emit around 50 tons of mercury pollution per year. This means large numbers of children are at risk of developmental problems. It is unfortunate that "mercury pollution will likely continue to grow in years to come because power hungry economies of China and India rely heavily on coal power plants to drive their economies forward which will lead to an increased coal-burning."

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  3. There are three forms of Mercury: methylmercury, elemental mercury and other mercury compounds. Methylmercury affects the nervous system primarily of fetuses, infants and children. With the ingestion of methylmercury, expecting mothers may give birth to children with severe disabilities despite very minimal symptoms. Methylmercury is not a cause of any forms of cancer according to scientists. Elemental mercury can be ingested when it is breathed as a vapor. Symptoms of elemental mercury ingestion include these: tremors; emotional changes insomnia; neuromuscular changes; headaches; disturbances in sensations; changes in nerve responses; performance deficits on tests of cognitive function. At higher exposures there may be kidney effects, respiratory failure and death. Exposure to mercury compounds results in everything from skin rashes, to nervous disorders to death. Exposure to mercury can easily be avoided by keeping fresh air ventilation constant. A more global solution is to decrease the amount of mercury used as waste (less coal power plants).

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  4. As both essays state, mercury pollution is a horrible thing, and humans have intensified its effects, therefore haring themselves. In the first essay, it says that studies have shown that mercury pollution is irreversible. This is exactly why we must come up with a permanent solution for this problem. According to the Minnesota Pollution Control Agency, most of the mercury pollution in the world comes from human activities. Humans release mercury into the atmosphere by burning coal and creating fluorescent lights and dental fillings. Fixing this problem is rather simple, but it requires time. All we must do is find ways to replicate the products without releasing mercury. It is also very important that this new method does not decrease how effective the products are.

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