Tool to check arsenic in water

Patna: With many arsenic-related cancer cases in several districts of Bihar, Prof Prasoon Bhattacharya, an India born Swedish scientist at the KTH Royal Institute of Technology in Stockholm, has devised a tool to check the level of arsenic present in water, said city-based environmentalist Dr Ashok Kumar Ghosh on Sunday. Munsell Colour Shades and Codes, the sediment colour tool for installation of arsenic-safe shallow tube wells, has four broad classifications, according to the presence of arsenic and its respective sediment colour, he said.
According to experts, there are four ways of tapping arsenic-safe water — absorption-based arsenic removal unit, reverse osmosis-based arsenic removal unit, rainwater harvesting, water from open well sources and tapping from middle and deep aquifer.
Studies conducted by Ghosh found that out of the three layers of aquifer (a body of permeable rock which can contain or transmit groundwater), only the first layer is having increased levels of arsenic.
As a matter of fact, water in Bihar is mostly being tapped from shallow aquifer (first layer) because of its availability at lesser depth, which might be one of the possible major reasons of arsenic-borne diseases. “Water from the other two layers can be tapped for arsenic-safe consumption now, because it has not been overexploited yet. People as well as the government agencies need to be made aware about the potential harm due to ignorance,” he said.
The shallow aquifer ranges up to 70 feet, varying according to locations. In Sitamarhi, it is available at 20 feet and in Patna it is at 40 feet below the ground, followed by middle aquifer (up to 150 feet) and deep aquifer (above 250 feet).
Dr Ghosh explained that the sediment colour tool can help identify the presence of arsenic in soil with colour of the sediment taken out of boring core. The tool has defined colours for different levels of arsenic presence.
A recent survey in arsenic-hit districts of the state conducted by the environment and water management department of A N College here ranked Buxar as the most affected with 1906 parts per billion (PPB) followed by Bhojpur (1861 PPB), Bhagalpur (1340 PPB) and Patna (840 PPB) on a list of 18 districts.