Health risk assessment due to fluoride exposure from groundwater in rural areas of Agra, India: Monte Carlo simulation

The present study deals with the assessment of the fluoride concentration from 60 different spatially distributed well locations and associated health risks to rural residents in the Achhnera block of Agra, Western Uttar Pradesh, India. Monte Carlo simulation and sensitivity analysis were applied to quantify uncertainties in risk estimation. Assessment of the human health risk was carried out using computations based on fluoride ingestion (EDIing), dermal absorption of fluoride (EDIder) and hazard quotient (HQ) in all three categorized groups, i.e., infants, children, and adults. Fluoride concentration analyzed was found to be ranging between 0.15 and 2.50 mg/L with an average value of 1.51 mg/L. More than 58% of samples analyzed surpassed the permissible level as per drinking water specifications. From the model obtained for non-carcinogenic risk due to water ingestion, values of IRw range between 55.4% and 62.5% in all the three exposure groups, while that of C-w ranges between 37% and 42.8%. Based on the HQ investigation it was found that infants were at maximum risk followed by children and the least affected were adults. Results showed that based on the sensitivity analysis, a definition of the probability distributions of CW, IRw, EF and SA is presented as the main factor to improve the accuracy of the result.