Human health risk assessment (HHRA) of fluoride and nitrate using pollution index of groundwater (PIG) in and around hard rock terrain of Cuddapah, A.P. South India

Groundwater is the most common source of drinking and irrigation in the world. As a result of human activities and natural processes, nitrate levels in most groundwater supplies in arid and semi-arid areas have risen in recent decades. As a result of human activities and natural processes, the levels of fluoride and nitrate in most groundwater supplies in arid and semi-arid areas have increased in recent decades. Thirty groundwater samples were taken from bore wells to learn about the contaminated situations of groundwater fluoride and nitrate in sections of Cuddapah, South India, and to determine the likely harm to the health of adults, children, and infants. In the study villages' wells, flouride concentrations range from 0.1–3.2 mg/L, with 40% of groundwater exceeding fluoride guidelines (1.5 mg/L) and Nitrate concentrations range from 23.2–110.8 mg/L, with 86.6% of groundwater exceeding nitrate guidelines (45 mg/L). 96% of groundwater exceeds the allowable THI values (>1) for adults (0.74–4.02), children (0.75–4.08), and infants (0.57–3.10). According to the PIG categorization, 23% of total groundwater samples fall into the low pollution zone (PIG: 1.38) whereas 47% of samples fall into the moderate pollution zone (1.83) and 30% of groundwater samples fall into the high pollution zone (2.20). Hence, appropriate preventative steps must be adopted to reduce the health risk in this area.