Abstract
Fluoride is present naturally in water at < 1.5 ppm and it is considered to be essential for dental and bone enamel mineralization forming fluorapatite. Chronic exposure (> 2ppm) is considered to be toxic and it leads to fluorosis. Fluoride in minor quantities is excreted through sweat, saliva and feaces. Kidneys are the major route of excretion of fluoride and are thus it is the primary organ to be affected. Therefore, it is of interest to assess urinary fluoride among school children with different blood groups at Kolar district, Karnataka, India. Study was conducted in 155 subjects, aged 16-17 years. Data shows that blood group B has high risk of effecting by fluorosis (mean value of urine fluoride = 1.11). However, subjects with negative blood groups are least affected by fluorosis (mean value of urine fluoride =0.30). However, a larger population study is required for validation.