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Abstract
Fluoride is one of the trace elements which belong to the halogen group which include also chlorine, iodine and bromide (Anderson, 1999). It occurs naturally in the earth’s crust, water and food as negatively charged ion. Approximately 99% of the fluoride is incorporated into bones and teeth (Beata et al., 2001).
Fluoride is one of the potent toxicants to which humans are exposed (Chinoy and Sharma, 1998). With progress in fluoride research, it has become evident that the toxic effects of excess fluoride involve all body systems (Zan-Doa, 1997).Chronic fluoride intoxication may play a role in the aetiology of the so-called repetitive strain injury (RSI) which is a new clinical syndrome, characterized chiefly by a sever pain wists, forearms, hands and fingers (Smith, 1985).
Czarbowsik and his associates (1996), found that increasing concentration of fluoride in water from 0 to 1ppm would increase the hip fracture rate by 40%. They also found that fluoride is actually altering the basic architecture of human bones. Prolonged and excessive intake by children during the period of tooth development before eruption can result in dental fluoosis characterized by motteled anamel with pitted eroded appearance (Harris and Clark, 1999). Also, Shi (1995) found bone abnormalities in aborted fetuses born to mothers with dental fluorosis.