The fluoride levels in 304 water samples from different sources in Bangladesh were determined using the proton induced gamma emission (PIGE) method. Concentrations vary from 0.02 to 2.32 mg/L with a mean of 0.43 ± 0.40 mg/L In tube well water the concentrations range from 0.02 to 2.32 mg/L for 163 samples with a mean of 0.56 ± 0.48 mg/L. Surface waters contain the lowest amount of fluoride with a mean of 0.14 ± 0.10 mg/L for 23 samples. In rain water the mean fluoride content is 0.26 ± 0.13 mg/L, slightly higher than in surface water. The concentration of fluoride in 102 city water supplies ranges from 0.03 to 1.10 mg/L with the mean of 0.33 ± 0.21 mg/L These results indicate that the fluoride level in groundwater is, in general, lower than the maximum official permissible limit of 1 mg/L in drinking water set for Bangladesh.
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