Thousands of people living in over hundreds of villages in different districts of Bihar and Sahebganj district of Jharkhand in India are facing serious threat to their health due to alarmingly high quantity of arsenic present in the underground water.
Bihar is facing one of the gravest natural disasters in the form of arsenic contamination of ground water. In the first detailed study of ground water quality, the Department of Environment and Water Management, AN College, Patna, has already submitted Interim Reports to PHED and UNICEF about the alarming findings on arsenic poisoning cases in the districts of Patna, Bhojpur, Vaishali and Bhagalpur. The study was conducted from April 2004 to May 2006, the study area being confined to 10 kms, wide belt along the Ganga river as per the instructions of PHED and UNICEF.
According to Dr Ashok Ghosh, Principal Investigator of Project Arsenic, Department Of EWM, AN College, these findings are just the tip of the iceberg, as more contaminated aquifers are waiting to be detected in the remaining parts of the State. The water quality testing was done initially by Field Test Kits and then confirmed by AAS or UV Spectrophotometric tests. Epidemiological studies indicate that drinking water having more than permissible arsenic levels of 10 ppb increases the mortality rates as arsenic is a bio-accumulative toxin.
Persons suffering from arsenicosis have not yet responded to known treatment procedures. The high intake of arsenic, along with under nourishment and lack of medical help have worsened the lives of the population in the arsenic affected rural areas. Arsenic can also contaminate standing food crops if it is present in the soil and soil water.
As Bihar plains are highly fertile and its crops are marketed to many distant places, apart from being locally consumed, it becomes imperative to test the levels of arsenic in the food chain too. What is worrisome is that arsenic contaminated ground water tables have abrupt occurrences both over time and space. This explains why a public hand pump in village Ramnagar in Maner tested 30 ppb in the post monsoon period and more than 60 ppb in the month of May. Also arsenic manifestation exists at different levels in different areas.
In north-west Maner, arsenic contaminated hand pumps have a shallow depth between 60 to 80 feet in the diara belt.
In Bhojpur, the depth of contaminated aquifers goes down to 150 feet away from new diara land, while in Vaishali, arsenic is found in the shallow and middle aquifers at an average distance of 5 km away from the river bank. Regular monitoring of drinking water from hand pumps is immediately required as a part of the mitigation strategy. Patna, the first district to be covered, revealed pockets of high arsenic contamination, above the acceptable limit of 10 ppb, in 171 villages in Maner, Danapur, Sampatchak, Barh, Bakhtiarpur, Fatuha, Khusrupur, Phulwari, Mokama, Pandarak and Patna.
1,060 village hand pumps were arsenic contaminated. The highest AAS reading of arsenic level in Government hand pump water is 724 ppb. Sampatchak Block has low contamination levels of below 50 ppb. In Bhojpur, the highest AAS test readings are 1861 ppb and 1,064 ppb in Pandey tola, Barhara Block, a situation far more serious than the one represented by the much-touted village Ojhapatti of Shahpur Block.
Out of the 6,292 hand pumps tested, 47.70 per cent were arsenic contaminated hand pumps. In Barhara, 62.84 per cent in Udwantnagar 59.39 per cent, in Shahpur 40.41 per cent, in Behea 37.17 per cent, in Koilwar, 29.20 per cent, and in Ara 25.88 per cent of Block level hand pumps were arsenic contaminated. In Vaishali, all the blocks covered within 10 km along the Ganga banks, has low level arsenic contamination at present.
In Bhagalpur district most affected areas are Kahalgaon, Pirpainti, Sabaur and Sultanganj. A detailed study has been presented on groundwater metal contents of Sahebgunj district in Jharkhand, with special reference to arsenic. Both tubewell and well waters have been studied separately with greater emphasis on tubewell waters. Groundwater of all the nine blocks of Sahebgunj district have been surveyed for iron, manganese, calcium, magnesium, copper and zinc in addition to arsenic. Groundwater of three blocks of Sahebgunj, namely, Sahebgunj, Rajmahal and Udhawa have been found to be alarmingly contaminated with arsenic present at or above 10 ppb.
Rivers flowing through the coal fields of Jharkhand have been reported to carry arsenic responsible for arsenic poisoning in downstream areas of West Bengal. The coal fields of Bachara and Piprawar areas of Jharkhand have contaminated the waters of the Damodar and its tributary, the Safi. According to author, arsenic contamination arises mainly due to the dumping of waste from the coal mines along the river bed. Coals of the area mentioned contains sufficient amount of arsenic.
Arsenic upto 608 parts per billion (ppb) was detected against the permissible limit of 10 ppb in some villages of Kahalgaon block in Bhagalpur district in 2005. Work was carried out by Dr Sunil Chaudhary of TM Bhagalpur University.
A detailed work was carried out by Dr Ashok Ghosh, Professor-in- charge, department of environment and water management, AN College, Patna, in the arsenic affected areas of Bihar. He found that out of 27,061 hand pumps, 7,218 pumps tested had arsenic contaminated water greater than 10 ppb (26.67 per cent). Highest arsenic value recorded was 1,861 ppb. Study also revealed that 87 per cent of the trivalent arsenic was found in the groundwater of Bihar.
The study by Bihar's Public Health and Engineering Department (PHED) reveals that the average arsenic content in drinking water in the 12 districts is 500 parts per billion (ppb). Patna is among the affected areas.
According to Dr Ghosh, a total of 16 Bihar districts (57 blocks) are affected by high level of arsenic in the groundwater. Worst-affected districts are Bhojpur, Buxar, Vaishali, Bhagalpur, Samstipur, Khagaria, Katihar, Chapra, Munger and Dharbanga.
A very alarming recent finding by the research group is the detection of high arsenic content (more than 50 ppb) in the water of River Jaminia — flowing parallel to River Ganga in Bhagalpur district of Bihar. This river merges with Ganga and water from this river is being supplied to urban Bhagalpur without any treatment, alarmed Dr Ghosh.
Alarmed by the severity of arsenic's impact on human body in these villages, the team also collected samples of hair and nail of affected persons for detail medical examination to ascertain the level of damage, said Principal Investigators Dr Ashok Kumar Ghosh and Nupur Bose of AN College Patna. The findings indicated that a wider area, including the fertile irrigational lands, was under the grip of arsenic.
According to another research report done by Dipanka Chakraborti in Semria Ojha Patti village in the Middle Ganga Plain, Bihar, where tube wells replaced dug wells about 20 years ago, analyses of the arsenic content of 206 tube wells (95 per cent of the total) showed that 56.8 per cent exceeded arsenic concentrations of 50 micro g/L, with 19.9 per cent greater than 300 micro g/L, the concentration predicting overt arsenical skin lesions.
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