Investigation of potential human health risks from fluoride and nitrate via water consumption in Sabzevar, Iran

High concentrations of fluoride and nitrate in drinking water cause significant impacts on human health. The aim of this research was to estimate the risk to human health induced by fluoride and nitrate due to the intake of the groundwater through drinking water in Sabzevar city, Iran. Eighteen groundwater samples were collected from nine wells in the region during 2018 to determine the fluoride and nitrate concentrations. The non-cancer risk, reflected by the hazard quotient (HQ) and the hazard index (HI), was assessed for adults, children and infants. The water samples had overall mean fluoride and nitrate levels in the range of 0.197-1.32 mg/L and 8.8-47.2 mg/L, respectively. All the wells had fluoride levels below the WHO guideline of 1.5 mg/L. For nitrate, all the wells were within the standard. Among the nine groundwater samples, the total HI values at 22%, 55% and 55% of wells exceeded safe levels of 1 for adults, children and infants, which indicates that the local groundwater is detrimental to these age groups in the mentioned locations. The results of this research could help to develop proper strategies for comprehensive water resource management, particularly by providing scientific documents for decision and management of groundwater sources applied for drinking water supply.