The water filter is planted at a school near Baruipur in South 24 Parganas of West Bengal is producing 10,000 litres of water per day.
“We are using arsenic-contaminated ground water and filtering it using electro-chemical arsenic remediation (ECAR) technology to produce potable water which is not only free of arsenic but all other contaminants,” said professor Joyashree Roy who is co-ordinating the project.
ECAR was developed by NRI scientist Ashok Gadgil in his Berkeley lab on energy and water research and has been successfully running in Bangladesh and Cambodia.
The technology uses electricity to quickly dissolve iron in water which leads to the formation of a type of rust that readily binds to arsenic in the water. As the rust aggregates forming larger particles, it is separated from the water through filtration.
Professor Roy said that once commercialised the cost of drinking water can be as low as one rupee a litre.
“Only the know-how is from outside, rest is indigenous. The materials used in making the plant are locally sourced. Our students of Environment Engineering know how to do everything,” Roy said.
The cost of licensing the technology is also little because the project is a joint collaboration between the department of science and technology of the Indian government and the US government for transfer of technology for public health benefit, Roy said.
The technology is now ready to be licensed by the University of California for commercial use in India.
Drinking arsenic-laced water over a long period of time results in various health hazards, including skin problems, skin cancer, and cancer of the bladder, kidney and lung, besides other diseases.
World Health Organisation recommends a maximum arsenic concentration of 10 ppb (parts per billion) in drinking water and ECAR treatment is capable of reducing arsenic to below 2 ppb.
No additional contaminants appear in the treated water as chlorine or UV disinfection is used for removal of biological contaminants, Roy said.
Arsenic contamination of groundwater is a serious health issue in states like West Bengal, Bihar, Uttar Pradesh, Jharkhand, Punjab, Haryana and Assam. Most of the affected districts are located in the Gangetic or Brahmaputra river basin.