Of the 341 blocks in the State, 81 blocks have water with more arsenic than the permissible limit and 49 blocks with more fluoride than the standard value.
North 24 Parganas district, where about 20 blocks are affected with arsenic contamination, is the worst affected and is followed by Nadia, where 17 blocks and Murshidabad with 14 blocks where arsenic in groundwater is higher than the limit. Certain blocks in South 24 Parganas, Malda, Howrah, Hooghly and Bardhaman are also affected by groundwater contamination.
The figures of the chemical degradation of groundwater were released on the basis of a preliminary reconnaissance survey conducted by the Department of Water Resources Investigation and Development and have been highlighted in the Budget speech of Minister Saumen Kumar Mahaptara, which was tabled in the Assembly earlier this week.
Arsenic contamination is a major health concern in the State. It is a cause of warts, skin lesions and even cancers.
Fluoride contamination of groundwater is mainly concentrated in Bankura, Birbhum and Purulia, located in the south western part of the State. Purulia district with 15 blocks having fluoride contamination is the worst affected.
The State government in assistance with the World Bank is upgrading the existing Central Chemical & Hydrological Laboratory under State Water Investigation Directorate. There are also schemes of construction of soil laboratory in the State, the State government pointed out.
One of reasons for the increased chemical contamination of groundwater is an ineffective water resource management.
The State government passed the West Bengal Groundwater Resources ( management, Control & Regulation) Act, 2005 for effective management of wat