Arsenic movement and traces in the groundwater from the Hetao area, Inner Mongolia

In the Hetao area of Inner Mongolia, Quaternary alluvial aquifers used for the water supply are contaminated by naturally occurring arsenic, which heavily affects the health of 200,000 local residents. This study on the isotopes of strontium and relevant elements contained in the groundwater as well as the arsenic in the groundwater and residents’ hair indicates that the arsenic originally derives from the upper reaches of this area where arsenic levels are high in groundwater, rock, and soil. Over, respectively, 44 km (work-line AA′) and 36 km (work-line BB′) away from there, the levels of arsenic in the water, corresponding to the trend of the residents’ arseniasis, decrease along the direction of the flow from 0.251 to 0.05 mg/L and 0.232 to 0.036 mg/L. The result of this research suggests that long-term strategies to deal with this arseniasis should involve finding hydrous terrains uncontaminated by water from the upper reaches and developing routes to prevent water from taking arsenic.