Extensive Arsenic Contamination Found in Groundwater Beneath Pakistan's Indus Plain: Researchers report widespread arsenic contamination of groundwater beneath the Indus Plain in Pakistan, posing a significant health hazard to the estimated 50 million to 60 million people who depend on that resource for drinking water. Regularly drinking water that contains high concentrations of naturally occurring arsenic, leached from host rocks and sediments, can lead to harmful health effects, including skin disorders, lung cancer and cardiovascular diseases. Arsenic contamination of groundwater is thus a health risk of global proportions, yet the magnitude of that risk is poorly known in many parts of the world. Small-scale studies in Pakistan have reported high arsenic concentrations in groundwater, but a lack of resources in the country has prevented wide-ranging evaluation. Here, Joel Podgorski and colleagues created the first comprehensive "hazard map" of this poisonous element for Pakistan, collecting groundwater samples from nearly 1,200 sites throughout the country, mainly from hand and motor pumps. The scientists then used statistical modeling to assess environmental factors that may be related to arsenic movement and the size of the human population exposed to arsenic, finding that much of the Indus Plain is likely to have elevated arsenic concentrations. They say this alarmingly high number of people likely affected demonstrates an urgent need to test all drinking water wells in the Indus Plain, and treat affected wells accordingly. They call for emergency solutions, including health intervention programs, finding alternative resources of drinking water and evaluating options for removing arsenic.