Spatial distribution of fluoride in groundwater resources in selected parts of Kurdistan Province, Iran, using the geographical information system

Fluoride in drinking water has a profound effect on teeth. Since drinking water is an important source of fluoride, the evaluation of the fluoride content of water resources is necessary. Temporal variations and spatial distribution of fluoride in drinking water of some selected parts of Kurdistan Province, Iran, have been studied using geographic information system (GIS) techniques. Thus, 40 villages were selected and 80 samples taken in two wet and dry seasons in 2013. Fluoride concentration was measured via ion chromatography (IC) method. Geospatial analysis of the data was performed using the ArcGIS software developed by Environmental Systems Research Institute (Esri). The results showed that the average fluoride concentration in drinking water ranged from 0.096 to 1.102 mg/l with the concentration being less than 0.50 mg F/l in 57 samples (71.25%), between 0.51 and 1.0 mg F/l in 21 samples (26.25 %), and greater than 1.0 mg F/l in 2 samples (2.5%). No difference was observed between the concentrations of fluoride in the two-stage sampling with the nonparametric Wilcoxon test (P > 0.01).