Ineffectiveness and Poor Reliability of Arsenic Removal Plants in West Bengal, India
“Decontamination plants installed at wells throughout West Bengal are failing to reduce arsenic in local drinking water to safe levels,” an article published in the July issue of the Nature journal has reported, quoting a report published in the Environment, Science and Technology magazine. “Of 18 arsenic-removal plants (ARP) monitored over a two-year period, none reduced arsenic levels below the maximum safe value stipulated by the WHO, says epidemiologist, Mr Dipankar Chakraborti of Jadavpur University whose team carried out the tests,” the Nature article said.
The article quoted the report titled, ‘Ineffectiveness and Poor Reliability of Arsenic Removal Plants in West Bengal, India’ published in the Environment, Science and Technology magazine. This report has been prepared by a team from the School of Environmental Studies, Jadavpur University and the Indian Statistical Institute. The members of the team are M. Amir Hossain, Mr Mrinal Kumar Sengupta, Sad Ahamed, Mohammad Mahmudur Rahman, Mr Debapriya Mondal, Mr Dilip Lodh, Mr Bhaskar Das, Mr Bishwajit Nayak, Mr Bimal K. Roy, Mr Amitava Mukherjee, and Mr Dipankar Chakraborti. According to the Environment, Science and Technology magazine, the revised manuscript of this report was received on 28 February, 2005 and and it was accepted on 9 March, 2005.
The Nature article goes on to say: “The findings come as a blow to efforts to address what has been called the worst mass poisoning in history, in which millions of people were exposed to dangerous or fatal levels of arsenic in their water. The arsenic comes from natural geological sources that weren’t recognised when the wells were dug during the 1970s. An estimated 35 million people were drinking from such wells, dug by aid agencies so that locals wouldn’t have to rely on rain and river water, which is often contaminated. To try to fix the situation, some 2,000 arsenic-removal plants were installed in wells in West Bengal, and many more in Bangladesh, at an average cost of US$ 1,500 each.”
Mr Chakraborti and his colleagues tested 18 such plants, from 11 different manufacturers in India, Germany and the United States. The average arsenic concentration in water treated during a two-year period was 26 micrograms per litre — more than twice the value recommended by the WHO. Only two of the plants met the Indian standard value for arsenic levels, which is five times higher than that of the WHO,” the Nature article adds. The original report published in Environment, Science and Technology says that: “Our 2-year study showed that none of the ARPs could maintain arsenic in filtered water below the WHO provisional guideline value (10g/L) and only two could meet the Indian standard value (50 µ/L) throughout.”
When asked to comment, Mr Asim Barman, state public health and engineering secretary, said: “ Their report is not correct. Some of the ARPs may have failed to attain the permissible standards, but all are not same. The state government, after all, has some responsibility and it has spent a lot of money in installing these ARPs (The Statesman, 1975).