Fluoride Action Network


Arsenic (As), and fluoride (F) are potent contaminants with established carcinogenic and non-carcinogenic impacts on the exposed populations globally. Despite elevated groundwater As and F levels being reported from various regions of Pakistan no biomonitoring study has been reported yet to address the co-exposure impact of As and F among school children. We aimed to investigate the effects of these two contaminants on dental fluorosis and intelligence quotient (IQ) along with the induction of oxidative stress in rural children under co-exposed conditions. A total of 148 children (5 to 16 years old) from the exposed and control group were recruited in the current study from endemic rural areas of Lahore and Kasur districts, Pakistan having elevated As and F levels in drinking water than permissible limits. We monitored malondialdehyde and its probable association with antioxidants activity (SOD, CAT, and GR) as a biomarker of oxidative stress. GSTM1/T1 polymorphisms were measured to find the impact of As on health parameters. Mean urinary concentrations of As (2.70 vs. 0.016 µg/L, P < 0.000) and F (3.27 vs. 0.24 mg/L, P < 0.000) as well as the frequency of dental fluorosis were found elevated among the exposed group. The cases of children with lower IQ were observed high in the exposed group. Additionally, lower concentrations of antioxidants (SOD, CAT, and GR) were found suggesting high susceptibility to F toxicity. The findings suggest that F accounted for high variations in health parameters of children under the co-exposure conditions with As.

*Original abstract online at https://link.springer.com/article/10.1007/s10653-021-01141-4



… In the present study, a higher frequency of individuals with severe level dental fluorosis was detected in the exposed area. In contrast, none of the individuals in the control area showed signs of dental fluorosis. This was due to the strong correlation of urinary F with dental fluorosis (R2 = 0.721, Table 2).

Exposure of contaminants particularly F caused significant neurotoxicity in the present study. …

… Furthermore, it was revealed that variations in dental fluorosis and IQ levels were more significantly associated with F exposure compared to As. Additionally, it was also observed that the induction of oxidative stress was more positively correlated with urinary F and dental fluorosis. Based on the results (Table 2,3, and 4), it was concluded that F was more negatively associated with the health effects on school children as compared to As. …


… A non-significant difference was observed in age and gender [male] distribution between the control and exposed groups according to x2 analysis.