66 Fluoride Vol. 33 No. 2 66-73 2000 Research Report ——————————————— For Correspondence: AR Shivashankara, a Department of Biochemistry, M.R. Medical College, Gulbarga - 585 105, Karnataka, India. b Department of Biochemistry, Kasturba Medical College, Manipal-576 119, Karnataka, India. A CLINICAL AND BIOCHEMICAL STUDY OF CHRONIC FLUORIDE TOXICITY IN CHILDREN OF KHERU THANDA OF GULBARGA DISTRICT, KARNATAKA, INDIA AR Shivashankara, a YM Shivaraja Shankara, a S Hanumanth Rao, a P Gopalakrishna Bhat b Karnataka, India SUMMARY: The prevalence of dental and skeletal fluorosis was determined among children of Kheru Nayak Thanda of Gulbarga district, where the fluo- ride concentration in drinking water ranges from 0.6 to 13.4 ppm and the water has low levels of copper and zinc. These children were investigated clinically, radiologically and biochemically. The study revealed that 89% of the children had dental fluorosis and 39% exhibited skeletal fluorosis. Serum samples of these children showed elevated levels of alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST), and decreased levels of total protein, albumin, and potassium. Radiographic changes suggestive of osteoporosis, osteosclerosis, and genu valgum were observed. Keywords: Fluorosis, Genu valgum, Genu varum, Osteoporosis, Osteosclerosis. INTRODUCTION Fluorine is the most electronegative element, distributed ubiquitously as fluorides in nature. Water is the major medium of fluoride intake by humans. 1 Fluoride can rapidly cross the cell membrane and is distributed in skeletal and cardiac muscle, liver, skin, 2 and erythrocytes. 3 Fluorosis is a major public health problem resulting from long-term consumption of water with high fluo- ride levels. It is characterized by dental mottling and skeletal manifestations such as crippling deformities, osteoporosis, and osteosclerosis. In India, as many as 15 states are affected by endemic fluorosis, and an ex- tensive belt of high fluoride in water and soil is reported in South India. 4-7 Gul- barga District of Karnataka was found to be a fluorosis endemic area by Naw- lakhe et al, 8 and AK Susheela. 9 However, a detailed survey for clinical manifestations attributable to fluoride toxicity has not been recorded. Children residing in Kheru Nayak Thanda, a village 35 km north of Gulbarga city, ex- hibited skeletal deformities from the waist downwards. In November 1998, the parents of these children brought them to the District General Hospital, Gul- barga, to be certified as physically handicapped. A survey was therefore carried out in the village. Drinking water samples were collected and analyzed for fluoride, copper, and zinc. The affected children were investigated clinically, radiologically and biochemically. Our findings are presented in this report. MATERIALS AND METHODS Kheru Nayak Thanda was created by the Karnataka State Government 8 years ago to provide shelter for the migrating, low socio-economic class of people. The area is a dry land with the temperature reaching 46ºC in summer.