Health Risk Assessment of Groundwater in Gaobeidian, North China: Distribution, Source, and Chemical Species of the Main Contaminants

The intensification of economic development, population growth, and energy consumption have led to the pollution of the groundwater in Gaobeidian City. This may exert great influence on human health. In the study, the chemical characteristics of the groundwater have been analyzed by Piper diagram and the possible health risks posed to the human health in Gaobeidian City has been evaluated using the model recommended by the Ministry of Environmental Protection of China. Furthermore, metal-species-weighted human health risk assessment is adopted for Cr6+, which is the major contributor to the carcinogenic health risk. The results show that groundwater is weakly alkaline, and the hydrochemical types is mainly Ca-HCO3. Non-carcinogenic pollutants mainly include arsenic (As), F−, and Fe. Carcinogenic pollutants mainly include Cr6+ and As. The carcinogenic risks of Cr6+ and As in the groundwater of all sampling sites greatly exceed their maximum acceptable limits, and contribution rate of Cr6+ is higher than that of As. The most important chemical species of Cr6+ is CrO42−, followed by CaCrO4(aq) and HCrO4−. The carcinogenic risk of above species is greater than the allowable limit. Among them, CrO4− exhibits the highest carcinogenic risk, and the maximum carcinogenic risk through ingestion to children and adults is 1.27E−03 and 5.98E−04, respectively. The economy in this area has developed rapidly because of its superior geographical location, but the groundwater pollution may have a great impact on the health of local residents, which must be paid attention to by local decision makers.