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Groundwater arsenic contamination in Bangladesh with its genesis and toxic effects on humans has been reported in many technical journals, conference proceedings and national daily newspapers. Recent studies in Bangladesh indicate that the groundwater is severely contaminated with arsenic above the maximum permissible limit of 0.05 mg/l for drinking water. Altogether 400 measurements were conducted in Bangladesh in 1996. Arsenic concentrations in about half of the measurements were above the maximum permissible limit. In 1998, British Geological Survey (BGS) collected 2,022 tube-well water samples from 41 arsenic affected districts. Laboratory tests revealed that 35% of these water samples had arsenic concentrations above 0.05 mg/l. Moreover, School of Environmental Studies (SOES), Jadavpur University, India and Dhaka Community Hospital (DCH), Bangladesh had jointly analyzed 22,003 tube-well water samples collected from 64 districts of Bangladesh between August 1995 and February 2000. Five years of sampling indicated that arsenic concentration in groundwater was above 0.01 mg/l in 54 districts and above 0.05 mg/l in 47 districts. The contemporary statistics indicate that 59 out of 64 districts of Bangladesh have been affected by arsenic contamination. In fact, arsenic contamination has become a serious problem in 16 districts of the country affecting 15 million people. The groundwater of Kushtia, Meherpur, Chuadanga, Jhenidah, Nawabganj, Naogaon, Khulna, and Rajshahi has been badly contaminated by arsenic. Arsenic has contaminated the ground water in about 85% of the total area of Bangladesh and about 75 million people are at risk. Since 95% of the population of Bangladesh is drinking groundwater, arsenic contamination has evolved into a serious health hazard. Arsenic is accumulating in humans through the intake of arsenic contaminated drinking water. As the people are also getting arsenic from food chain, the problem is growing more severe. SOES and DCH performed a field survey for arsenic patients in 32 districts of Bangladesh. The researchers analyzed a total of 5440 hair, 5321 nail, 1125 urine, and 820 skin scale samples collected from 210 arsenic affected villages. The results of analysis reveal that over 80% hair samples were found to contain arsenic above toxic level. Arsenic concentrations were also above the normal ranges in more than 90% nail and 95% urine samples. The normal concentration of arsenic in hairs is 0.08?0.25 mg/kg and 1 mg/kg indicates the toxic level. The normal arsenic content in nails is 0.43?1.08 mg/kg and the normal amount of arsenic in urines ranges from 0.005 to 0.040 mg/day. Field and Laboratory investigations of SOES and DCH have reported that the arsenic contents in hairs, nails, urines and skin scales of the affected people in Bangladesh are very high. This indicates that arsenic is being ingested in humans at a rate faster than it can be excreted. Therefore, many people in Bangladesh are suffering from arsenic driven diseases. Patients with arsenical skin-lesions have been identified in 30 out of 32 districts surveyed by SOES and DCH. Melanosis and keratosis are the most common manifestations among the arsenic affected people. Besides, patients of leuco-melanosis and hyperkeratosis have been found in many cases. Few cases of skin cancer, gangrene and Bowen?s disease have also been identified. In brief, the majority of the people in Bangladesh are grappling with an arsenic driven health crisis. Indeed, the magnitude of the arsenic problem in Bangladesh surpasses the aggregate problem of all the twenty countries of the world where groundwater arsenic contamination had been reported. This is the worst case of arsenic conta |
