Study and health risk assessment of the occurrence of iron and manganese in groundwater at the terminal of the Xiangjiang River.

The pollution of the surface water in the Xiangjiang watershed in China has received much attention, whereas the groundwater conditions in the area have long been ignored. This study investigates the occurrence of Fe and Mn in the groundwater of Chengxi Town located at the terminal of the Xiangjiang River. The study area was monitored for an entire year. Thereafter, the associated health risks were identified. Results showed that approximately 81 and 73 % of the measured samples exceeded the limits for Fe and Mn in Chinese drinking water, respectively. pH level was found to be negatively correlated with the concentrations of Fe and Mn in the groundwater in the study area. The occurrence of Fe in the groundwater showed significant seasonal fluctuations and was possibly affected by the change in environment conditions within the aquifer. By contrast, Mn remained relatively stable in most of the area during the whole year. Overall, no health threats for adults and children in the study area were determined according to the low health index values. Nevertheless, research attention and the implementation of relevant measures are needed for certain villages with exceptionally high Mn concentrations in the groundwater.