The authors record the results of their clinical examination of 78 workers engaged in the crushing and refining of cryolite. Beside silicosis — to as much as the second degree — which was present in 39, the following three diseases were found to be common in these workers:
1) a curious sclerotic affection of bones, ligaments, and muscular attachments, probably due to the deposition of calcium-fluoride in the bones The authors believe that the occurrence of this disease in man has not been described before. It was found in 30 of the workers examined.
2) an acutely arising and acutely revolving affection of the stomach, supposedly due to a slight corrosion of the mucous lining of that organ, owing to some of the fluorine contained in the swallowed cryolite-dust being changed by the hydrochloric-acid of the stomach into hydrofluorine.
3) a pronounced oligemia, found in 11 of the 30 workers in whom pathological changes in the bones were observed.
These changes in the bones are described in detail, and the causes of their occurrence, as well as that of the other symptoms, and the connection of these with the fluorine contained in the cryolite, are discussed.
The results of the investigation are compared with those of an investigation made of 21 other workers from industries where fluorine and materials containing fluorine are used. Also animal experiments with experimental feeding with cryolite are spoken of, but a more detailed description of these is reserved for a future communication.
Finally, the authors speak of experiments with a fluorine therapy for certain bone diseases, and suggestions for such a therapy; but also those experiments are in the nature of a preliminary communication.