Serum Phosphatase Activity in Generalized Osteosclerosis Due to Chronic Fluorine Intoxication in Man

Abstract

Flemming Miller and Gudjonsson 1 called attention to a peculiar form of generalized osteosclerosis, hitherto unknown, occurring in Danish workers exposed to dust of cryolite, a fluorine compound (Na₃AlF₆). The condition is characterized 1 2 3 4 5 by a diffuse increase in density of the bones, particularly of the spine, pelvis and ribs, and by calcification of ligaments and tendinous muscle attachments. Because of marked periosteal proliferation and the calcification of contiguous fibrous tissues, the sclerotic bones are often irregular in contour. There may be considerable impingement also upon the medullary cavity. The spine and thoracic cage ultimately become rigid, resulting in loss of mobility and vague “rheumatic” pains; but clinical signs and symptoms are otherwise remarkably few, even in advanced cases. At necropsy, 2 ; 3 4 5 6 the sclerosed bones are found to be heavy (up to 3 times the normal weight) with rough surface and relatively brittle texture. Histologically, the peculiar if not pathonogmonic osseous structure is characterized by the partial deposition of lime salts in the form of irregular granules. The fluorine content of the bone ash 2 3 4 5 is increased to about 10 times the normal values.

While distinctly less common than abnormalities of dentition, (“mottled enamel”), 19 skeletal changes due to chronic fluorine intoxication probably occur more widely in man than is generally appreciated. A number of cases of osteosclerosis have been reported from North Africa 7 and from India. 8 In the United States, Bishop 5 recently described typical skeletal changes in a man who for 18