A Systematic Review on Fluoride Contamination in Water Resources of Iran from 2016 to 2023: Spatial Distribution and Probabilistic Risk Assessment (Monte Carlo Simulation).

Because of significant variations and existence of high fluoride (F) in some waters, Iran has been considered for various fluoride studies in recent decades. Nevertheless, there is a no updated review on fluoride levels especially including F risk assessment. Thus, this systematic review is mainly aimed to evaluate the spatial distribution of F content in water sources of Iran using geographic information system (GIS) and conduct the health risk assessment. Besides, the Monte-Carlo Simulation technique with 10,000 iterations was applied for determination of the non-carcinogenic effects of F in different exposed groups (infant, children, teenagers, and adults). The results indicated that the maximum and minimum concentrations of F content were related to Jazmourian (Roudbar plain) (4.8 mg/L) and Sahneh (0.1 mg/L) provinces, respectively, and F content of more than ≅ 19% of the samples exceeds the Iranian standard value (1.5 mg/L). The results showed that the HQ of F in all groups were higher than 1 with the order of children > infants > teenager > adults in which children were the vulnerable group to F consumption in study area. Therefore, it is necessary to monitor and continuously measure water supplies for fluoride content and control measures, including removal steps, be taken for human risk reduction.