Probabilistic Risk Assessment of Exposure to Fluoride in Drinking Water in Victoria de Durango, Mexico

Abstract

In Mexico, it is estimated that millions of people are affected by the presence of fluoride in groundwater. In wells in the Guadiana Valley in Durango, Mexico, the presence of fluoride has been identified, exceeding the maximum allowable limit established by Mexican regulations (1.5 mg/L). The main purpose of this study was to evaluate the non-carcinogenic risk to the health of the adult population due to fluoride contamination of water, using a Monte Carlo simulation. To this end, the wells were monitored, fluoride concentrations were analyzed according to Mexican regulations and possible concentrations in the vicinity of the sampling zones were determined by applying the ordinary Kriging geospatial tool. Crystal Ball software was used for the simulation, also using data collected through surveys. In terms of dental fluorosis, around 30% of the population mentioned through surveys as having some characteristic of this disease. Of the 70 wells and 2 tanks that were sampled, 90% of them were found to exceed the levels allowed by the regulations. In more than 70% of the wells, the adult population had a non-cancer hazard quotient (HQ) greater than 1. Overall, the HQ for ingestion exceeded 1.8 at the 95th percentile, indicating a significant risk of fluoride-related health problems for the population.