Abstract:
The fluoride contamination in drinking water is
already gone to the alarming level and it needs the
immediate involvement and attention of all people to solve
this problem. Fluoride problem is higher in hard rock terrains
in worldwide and Madurai is such type of hard rock
region. Totally 54 samples were collected from the
Madurai district of Tamilnadu with respect to lithology.
The samples collected were analysed for major cations and
anions using standard procedures. The higher concentration
of fluoride is noted in the Charnockite rock types of
northern part of the study area. 20 % of samples are below
0.5 ppm and 6 % of samples are above 1.5 ppm exceeding
the permissible limit. The affinity between the pH and
fluoride ions in groundwater suggests that dissolution of
fluoride bearing minerals in groundwater. The higher
concentration of fluoride ions are observed in the lower EC
concentration. The isotopic study suggests that fluoride is
geogenic in nature. In factor scores, fluoride is noted in
association with pH which indicates the dissolution
process.
