Fluoride in Drinking Water and its Toxicosis in Tribals of Rajasthan, India

Fluoride (F) toxicosis in the forms of dental, skeletal and non-skeletal fluorosis were investigated in 996 tribal individuals (503 males and 493 females) above 10 years of age living in nine F endemic villages of Dungarpur district of Rajasthan, India. Drinking water sources of these villages contained F in the range of 1.5-4.4 ppm. Of these tribals, 735 (73.8 %) and 294 (29.5 %) were found to be afflicted with mild to severe dental and skeletal fluorosis, respectively. At 1.5 ppm F concentration the prevalence of dental and skeletal fluorosis was 33.9 and 10.7 %, respectively. A polymorphism of dental fluorosis in the form of brown to deep yellowish bilaterally stratified horizontal lines, pits or patches, and fine dots or granules was noted on anterior teeth of tribal individuals. Irregular wearing, excessive corrosions (abrasions), dark-yellowish pigmentation of exposed cementum and dentine material, diastemas between teeth, pronounced loss of tooth supporting bone with recession, and bulging of gingiva (gum) were also present. Among the adult and old tribal individuals, the following mild to severe manifestations of skeletal fluorosis such as crippling, kyphosis, invalidism and genu-varum syndrome were found. Sporadic cases of paraplegia and quadriplegia were also found. None of the fluorotic tribals showed evidence of genu-valgum syndrome. Radiological changes were also observed in these individuals. Other signs of chronic F intoxication in soft tissues (non-skeletal fluorosis) included colic, intermittent diarrhoea or constipation, bloating, urticaria, polyurea, polydipsia, repeated abortions, still birth and sterility. Data pertaining to prevalence of osteo-dental fluorosis in relation to age and F concentration exhibited statistically significant correlation.