Hydrogeochemical appraisal of groundwater quality and health risk in a near-suburb area of North China

The present study was conducted to appraise the suitability and human health risk of groundwater in a rapid urbanization area of North China. Groundwater samples were collected from phreatic and confined aquifers throughout the study area during pre- and post-monsoon seasons. Results show groundwater, regardless the depth, is slightly alkaline in nature and relatively fresh with the total dissolved solids within 600 mg/L. The hydrochemical facies of phreatic and confined groundwater are dominantly HCO3-Ca·Mg, followed by HCO3-Na. Groundwater in the study area, regardless the depth, is suitable for irrigation with almost no salinity and sodium hazards if proper drainage measures are undertaken. The entropy weight water quality index evaluating results show all phreatic and confined groundwater is suitable for drinking purposes. The overall potential non-carcinogenic risk posed by nitrogen (NO3-N, NH4-N) and heavy metals (As, Zn, Fe, Mn) through drinking water ingestion exists in the southwestern area and a small local area in the central study area, and is higher for children. Special attention should be paid to the arsenic because its hazard quotient was very high in some local areas. This study will benefit the protection and utilization of groundwater in near-suburb areas around the world.