GUWAHATI, Jan 25 � A joint survey conducted by the State Public Health Engineering Department (PHED), UNICEF and the IIT, Guwahati has found that 7,22,603 people of 1, 970 habitations in 73 development blocks of 18 districts of the State are at risk of arsenic poisoning. Assessment of ground water quality in three development blocks in Dhemaji district in this respect is yet to be completed.
Altogether, 4,464 of the 56,180 ground water sources used for drawing drinking water tested in these development blocks under the survey, between 2005 and 2010, have been shown to be containing the poisonous material beyond the permissible limit of 50 part per billion (ppb --- equivalent to micro-milligram) per litre. For the survey, BTAD was treated as an integrated district.
The affected districts include - Goalpara, Dhubri, Bongaigaon, Barpeta, Nalbari, Kamrup, Darrang, Sonitpur, Lakhimpur, Sivasagar, Jorhat, Golaghat, Nagaon, Morigaon, Cachar, Hailakandi, Karimganj and the BTAD areas. The condition of Jorhat PHE Division is found to be the worst in this respect, with 366 habitations of the division found to be affected by the phenomenon.
Significantly, 794 drinking water sources used by different schools of the State are also found to be containing arsenic beyond the permissible limit of 50 ppb.
This has been revealed by former Chief Engineer of the Public Health Engineering Department (PHED) AB Paul, quoting official documents concerning the outcome of the joint survey. The findings of the survey were disseminated at a workshop here yesterday.
It needs mention here that under Paul's stewardship as the Chief Engineer, the PHED could detect for the first time, presence of arsenic beyond the permissible limit of 50 ppb in the drinking water sources of Mankachar area of Dhubri district in December 2003 and of Sadarashi area of Karimganj district in January 2004. Detection of these cases led to the above survey.
The Government of India (GoI) accepted the 50 ppb norm for determining the safe limit of arsenic in drinking water considering the economic and technical issues connected with it. However, the World Health Organisation (WHO) has accepted 10 ppb of arsenic in a litre of water as the safe limit so far as drinking water is concerned.
If the WHO criterion is followed in this respect, then 16,742 drinking water sources would be required to be declared as unsafe because of their containing arsenic beyond the permissible limit, said Paul.
Arsenic is bio-accumulative and proven carcinogenic, besides being a contributory agent for many more such diseases. Scientists in the developed countries are now pleading for lowering further the permissible limit of presence of arsenic in drinking water.
In the developed countries, the general health condition of the people is much better than that of the countries like India. The adverse impacts of arsenic on human body depend more on all the parameters like body weight, nutrition, food intake and immunity, said the sources.
Drinking more water is also vital for the people of the tropical countries like India. This has made the people of these countries more vulnerable to arsenic poisoning if they go on drinking water contaminated with arsenic, Paul said.
Paul was the first Government official who detected the cases of fluorosis in Karbi Anglong district of the State and this led to detection of presence of excess fluoride in the drinking water of several districts of the State in the end part of the last century.
The two findings of presence of excess fluoride and arsenic by Paul with the help of the School of Environmental Science, Jadavpur University changed the whole scenario concerning drinking water quality of Assam.
An official paper said here today that the actual number of arsenic-affected habitations in the State has gone up to 2,581 with the latest findings, as, 611 habitations were earlier found to be affected by the phenomenon. However, the paper is silent on what would be the size of people at risk if 611 more habitations are added to the list.