The Irrawaddy Delta, Myanmar is a high-risk area for groundwater contamination with arsenic, suggests research published online this week in Nature Geoscience. By inferring arsenic levels in groundwater from the Earth’s surface properties, the researchers present an arsenic risk map for Southeast Asia.

Michael Berg and co-authors created a statistical model that links geological features and properties of the surface soil to the risk of arsenic contamination in groundwater. They independently verified their model with a field survey in a region of southern Sumatra, Indonesia, where arsenic levels had not previously been measured. The resulting arsenic risk shows several known sites of contamination, and also reveals high risk zones in Sumatra and the Irrawaddy Delta of Myanmar, where no measurements of arsenic in groundwater are available.