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Ô Nhiễm Arsenic (Thạch Tín)

The US Environment Protection Agency defines arsenic as a persistent, bio-accumulative, and toxic chemical having the ability to accumulate in the air, soil, and water. In 1961, the pollution of arsenic was first discovered in Taiwan, and later in Belgium, Netherland, Germany, Italy, Hungary, Portugal, The Philippines, Ghana, USA, Chile, Mexico, Argentina, and Thailand. In 1992, the toxicity of arsenic was found as a disaster in West Bengal, India. Recently, the problem of arsenic in Bangladesh has been more serious and affected more than 23 million people in 1997, and the number rose to almost 60 million in 2005 | Ô Nhiễm Arsenic Thạch Tín Summary The US Environment Protection Agency defines arsenic as a persistent bio-accumulative and toxic chemical having the ability to accumulate in the air soil and water. In 1961 the pollution of arsenic was first discovered in Taiwan and later in Belgium Netherland Germany Italy Hungary Portugal The Philippines Ghana USA Chile Mexico Argentina and Thailand. In 1992 the toxicity of arsenic was found as a disaster in West Bengal India. Recently the problem of arsenic in Bangladesh has been more serious and affected more than 23 million people in 1997 and the number rose to almost 60 million in 2005. Where does arsenic come from Scientists conclude that the deposition of the arseno-pyrite deep in the ground for millions of years has been carried deep into deep into the underground water and the river sources. In industry arsenic is used as an alloy with other metals such as iron copper lead mercury nickel and cobalt. It is also used as an anti-bacterial solution to treat wood used as electrical poles. Pure arsenic is not toxic but when it is combined with other chemical compounds to form arsenite As3 and arsenate As5 it becomes very dangerous. Human absorption of arsenic usually takes place through water and foods. The deadly human disease is caused by the intake of animal meat shrimps and fish living in an environment contaminated with arsenic. Porcelain cooking ware fabricated in China may also cause disease due to presence of arsenic. The people in Bangladesh who have been used the water from the wells built by UNICEF for a quarter of a century still do not know the disastrous presence of arsenic in the well water. Until 1988 The National Arsenic Committee in Bangladesh was established in order to solve the problems involving more than 4000 affected villages. Even this country has the support of UNICEF UNDP UNEP and WB the arsenic problems still remain a calamity of the world nowadays. The perspective of the pollution of arsenic in the