In the present study, the health risk assessment of exposure to uoride in drinking water of southern Iran province was performed with a de nite and probabilistic approach. Monte Carlo simulation and sensitivity analysis were used for uncertainty in risk estimation. The results showed that uoride concentration ranged between 0.1-0.9 mg/l with an average of 0.454 ± 0.205 mg/l. The distribution function followed the normal distribution. The highest uoride concentration was observed in the central and northern regions of the province. Also, the lowest concentration was obtained 0.01 mg/l. In the de nitive method, the non-carcinogenic risks associated with uoride in drinking water were in acceptable range (HQ < 1). Conducting Monte Carlo simulation indicated that the potential non-carcinogenic risk for children in the 95th percentile exceeded the safe limit of 1, which showed that there were a potential noncarcinogenic in this group. Sensitivity analysis showed that uoride concentration and water consumption had the most considerable effect in the model. Therefore, consumption of water and foods containing uoride along with excessive consumption of tea may increase human's health risks. Therefore, continuous monitoring of water sources in terms of uoride concentration along with proper diet training for residents of this province should be done.

In the present study, the health risk assessment of exposure to fluoride in drinking water of southern Iran province was performed with a definite and probabilistic approach. Monte Carlo simulation and sensitivity analysis were used for uncertainty in risk estimation. The results showed that fluoride concentration ranged between 0.1–0.9 mg/l with an average of 0.454 ± 0.205 mg/l. The distribution function followed the normal distribution. The highest fluoride concentration was observed in the central and northern regions of the province. Also, the lowest concentration was obtained 0.01 mg/l. In the definitive method, the non-carcinogenic risks associated with fluoride in drinking water were in acceptable range (HQ < 1). Conducting Monte Carlo simulation indicated that the potential non-carcinogenic risk for children in the 95th percentile exceeded the safe limit of 1, which showed that there were a potential non-carcinogenic in this group. Sensitivity analysis showed that fluoride concentration and water consumption had the most considerable effect in the model. Therefore, consumption of water and foods containing fluoride along with excessive consumption of tea may increase human's health risks. Therefore, continuous monitoring of water sources in terms of fluoride concentration along with proper diet training for residents of this province should be done.