Hydrology: Anthropogenic Arsenic
Arsenic occurs naturally in the groundwater of southern Asia. Analyses of an agricultural site in Bangladesh suggest that human activities, including widespread farming practices, can dictate where elevated arsenic is found.
Benner, Shawn. (2010). "Hydrology: Anthropogenic Arsenic". Nature Geoscience, 3(1), 5-6. http://dx.doi.org/10.1038/ngeo726