A new Duke University-led study has found widespread uranium contamination in groundwater from aquifers in 16 Indian states. The main source of the contamination is natural, but human factors (such as groundwater-table decline and nitrate pollution) may be exacerbating the problem. Several studies have linked exposure to uranium in drinking water to chronic kidney disease. The new findings are the first to demonstrate widespread prevalence of uranium in India’s groundwater. The WHO has set a provisional, safe drinking-water standard of 30 micrograms of uranium per liter, a level that is consistent with US EPA standards. Despite this, uranium is not yet included in the list of contaminants monitored under the Bureau of Indian Standards’ Drinking Water Specifications.