[Study on determinationing the bone mineral content as diagnostic value for occupational fluorosis].

The results of determination of the bone density of 194 workers exposed to fluorine by SPA-III type osteodensimeter were compared with people unexposed to fluorine, and with the results of diagnosing the luorosis by X-ray. (1) The abnormal bone cortex thickness and density rate in the people exposed to fluorine was significantly higher than the ordinary people (P < 0.05). (2) In the people exposed to fluorine, the correspondency rate of determining fluorosis of bone by X-ray and by osteodensimeter were 84.6%, and results of the two methods had no significant difference (P > 0.05). (3) In another group of 155 cases, whose values of hair fluorine and urinary fluorine were higher than the ordinary people (66.5%), the abnormal density of bone of 103 cases had been determined by osteodensimeter, but not by X-ray. This showed that the diagnosis of early changes of osteofluorosis by osteodensimeter was more sensitive than by X-ray. (4) There was close association between the unusual rate of osteodensity and the superstandard rate of hair fluorine and urinary fluorine. The above findings indicated the determination of bone density can be used as a diagnostic index for occupational fluorosis.