Fluoride concentration in drinking water sources and associated health risks

Background: Studies have shown that fluoride is present in various natural sources and plays a key role in preventing tooth decay. However, excessive exposure has been linked to adverse health effects. In recent years, cases of dental fluorosis have been reported in areas of Mexico City, including the Tláhuac municipality, where it had not previously been observed. Objective: To determine fluoride concentrations in tap water and assess associated health risks in the Tláhuac municipality. Material and Methods: Twenty-four neighborhoods within the Tláhuac municipality were selected and divided into three zones: North, Central, and South. Fluoride levels were quantified using the ion-selective potentiometric method with the Orion 4 Star instrument (Thermo Electron Corporation). Health risk assessment was conducted using the US-EPA model, considering both adult and child populations in the study area. Results: The mean fluoride concentration in Tláhuac was 0.700 ± 0.0934 mg/L, ranging from 0.539 to 0.934 mg/L. The estimated risk values were 0.24 ± 0.02 mg/L for adults and 1.5 ± 0.15 mg/L for children. Conclusions: The findings indicate that fluoride concentrations in Tláhuac's drinking water exceed recommended safe intake levels for children. The hazard quotient for children was greater than one, suggesting a potential risk of adverse health effects.