Occurrence and Health-Risk Assessment of Trace Metals in Raw and Boiled Drinking Water from Rural Areas of China

In order to assess the exposure of rural residents to trace metals via drinking water ingestion, 222 drinking water samples of rural areas from 8 provinces in China were collected and 18 trace metals analyzed by inductively coupled plasma mass spectrometer (ICP-QMS). Based on metal concentrations, the health-risk assessment such as chronic daily intakes (CDI) and hazard quotient (HQ) were calculated. Results showed that most metals occurred in the drinking water at very low concentrations, indicating a general good quality, while the concentrations of As, Pb and Zn in some samples from Qinghai, Yunnan and Hunan provinces were higher than World Health Organization (WHO) and Chinese guidelines for drinking water. The values of CDI and HQ indicated a negligible health risk for most Chinese rural residents via drinking water. However, high concentrations of As in drinking water from Qinghai province would pose a serious risk to the local inhabitants. More attention and intensive study should be paid to Zn, Pb and As contents.