Evaluation of Groundwater Quality and Health Risk Assessment of Nitrate Concentration in the Rayen Basin, Kerman, Southeast Iran

Abstract

Abstract The problem of poor water quality has spread throughout the world, especially in areas where water is scarce. Groundwater hydrochemistry and its controlling factors are crucial for human development and global ecosystem stability. The objective of this investigation is to provide a basis for the scientific advancement and sustainable use of groundwater in the Rayen basin in southeast Iran. Furthermore, the study offers data and theoretical support for both the superior development of the study area and ecological protection. In the study area, physiochemical parameters such as temperature, pH, conductivity, and total dissolved solids (TDS), as well as the concentrations of major anions (Cl−, HCO3−, CO32−, NO3−, and SO42−) and major cations (K+, Na+, Ca2+, and Mg2+) have investigated. These factors are vital in determining how well-maintained and useful water bodies. The assessment included the Drinking Water Quality Index (WQI), Groundwater Pollution Index (GPI), and the Nitrate pollution index (NPI) to determine the suitability of Rayen groundwater for human consumption. Through the study the groundwater 120 samples from the Rayen basin, Kerman have been obtained and it has been computed that the GPI values there fall in the range of 0.17 to 9.14 with an average of 1.75. A little less than 47% of samples were reported to be acceptable for drinking due to their low pollution levels. About 9% of them also were characterized as low, another 14% as moderate, 11% were seen as having a high level of pollution, and 19% were regarded as very high which makes them unadvisable for drinking directly. The WQI values shows that 32% of groundwater samples with poor and very poor quality are inappropriate for direct human consumption and requires treatment and only 68% of samples have good water quality. Another thing to consider is that the NPI is varied and ranges between − 0.25 and 4.65. Our findings indicated that the human activities, especially in agriculture and urban areas, as a result of excessive fertilizer use in agriculture also have a significant impact on groundwater solutes.