Aquifers in as many as 16 States in the country are contaminated by uranium, whose presence in drinking water has been linked to chronic kidney disease by several studies, a recent study has shown.
More importantly, uranium doesn’t figure on the list of contaminants monitored under the Bureau of Indian Standards’ drinking water specifications.
The study was carried out by a team of researchers led by Avner Vengosh, professor of geochemistry and water quality at the Nicholas School of the Environment at Duke University in the US.
The WHO has set 30 parts per billion as the provisional safe drinking water standard for uranium.
The study appeared in a recent issue of the journal Environmental Science and Technology Letters.
The scientists, who analysed data from 68 previous studies of groundwater geochemistry in Rajasthan, Gujarat and 14 other states, also found the problem is widespread in many aquifers in 26 districts in northern States such as Punjab and Haryana as well as some districts in southern and eastern States.
“One of the takeaways of this study is that human activities can make a bad situation worse,” Vengosh said.
“The results of this study strongly suggest there is a need to revise current water-quality monitoring programmes in India and re-evaluate human health risks in areas of high uranium prevalence,” Vengosh said.
According to Rachel Coyte, a PhD student in Vengosh’s lab, over-exploitation of groundwater for irrigation may contribute to the problem.
Many aquifers are composed of clay, silt and gravel carried down from Himalayan weathering by streams or uranium-rich granitic rocks.