ARSENIC POLLUTION AND HEALTH HAZARD IN CENTRAL INDIA BY NATURAL AND ANTHROPOGENIC EMISSION OF ARSENIC

Arsenic toxicity is now-a-days global problem due to excessive use of ground water and huge exploitation of natural resource materials. The ground water arsenic contamination has been found in many countries i.e. Bangladesh, Argentina, Chile, China, India, Mexico, Taiwan, Thailand and the United States, and is a global problem. The arsenic hazard now appeared as a ‘real disaster' in several countries. Tens millions of persons in many districts of India and Bangladesh are suffered by drinking ground water with arsenic concentrations far above acceptable levels. Thousands of people have already been diagnosed with poisoning symptoms, even though much of the at-risk population has not yet been assessed for arsenic-related health problems. After several years of low-level arsenic exposure, various skin lesions appear. These are manifested by hyper-pigmentation (dark spots), hypo-pigmentation (white spots) and keratoses of the hands and feet. The main source of arsenic in drinking water is arsenic-rich rocks through which the water has filtered. It may also occur because of mining or industrial activity in some areas. The quantity of arsenic released by human activities exceeds amounts released from natural sources by at least 3-folds. The major sources of arsenic release to the environment are smelters, coal-fired power plants, and pesticides. Air, water, and soil levels of arsenic are highest near smelters. Urban air is far more contaminated than air in remote areas, and water and soil concentrations are far higher in areas where arsenic-mineral deposits are mined. The aim of this presentation is to discuss the arsenic contamination levels, sites, sources, exposure and accumulation in plant and food and health hazard in the most industrialized region of India, Chhattisgarh state. The most of the mineral i.e. iron pyrite, dolomite, alumna, etc. and coal of the Indian subcontinent is deposited in the central region. They contain arsenic at traces. The anthropogenic activities i.e. mining, roasting of ores, burning of coal distributes arsenic in the environment. Arsenic is very soluble element and ultimately it settles in the ground water. In addition, the overuse of the ground water in the bedrock contaminated area also cause emission of arsenic in the water. Arsenic exists in three common valence states: As(0), As(III) and As(V). Arsenic-containing compounds vary in toxicity to humans according to valence state. Inorganic As is generally more toxic than organic As. In this region, As mostly exists in the inorganic form such as As(III) and As (V). The extreme levels of the arsenic in the soil, sediment, sludge, water, biomass and animals were detected. The highest level of the arsenic (> 500 mg/kg) in the soil and sediment of Koudikasa area, Rajnandgaon, Chhattisgarh, India was detected. The huge steel plant sludge is found to contain arsenic up to maximum 30 mg/kg. The maximum level of As detected in soil in the coal-burning site is 50 mg/kg. The ground water is widely used for drinking purposes. The water over a large area is contaminated with arsenic beyond the permissible limit due to natural and anthropogenic emission of arsenic. Arsenic has good tendency for to accumulate in the food and biomass chains. In much area, the surface dust is also contaminated with As. Several As exposures for entry in the humans are seen. How As metabolised in the humans of this region is discussed.

Contribution proposed for:   oral presentation