Letters Sent to Lt. Colonel J.F. Siler, June 26, 1928

COPY June 26th,1928. J. F. Siler, Lt. Colonel, Medical Corps. War Department, Office of the Surgeon General, Washington, D. Re: S.G.O. 230. 61-1 Dear Sir: Early in 1924, it was called to our attention that there was possibly an industrial hazard existing in our work, namely - the application of luminous material to watch and clock dials, etc. At the outset the hazard was ascribed to phosphorus, by a dentist who had occasion to do some dental work fora girl who had been working at our plant. He stated that this girl displayed a typical phosphorus jaw. Investigation, of course, proved conclusively that luminous material contains no phosphorus, but that the inference that phosphorus was probably present came from the common way of speaking of zinc sulphide, which glows when exposed to either light or radium rays, namely phosphorescency. We immediately took steps to ascertain as to what if any hazard existed in the application of this material, and in this connection we had a survey of our employees made by the Life Extension Institute of New York City, who reported that there apparently did not exist any industrial hazard among our employees. Later we called Dr. Cecil K. Drinker, at the suggestion of the New Jersey Zinc Company, to make a survey of the situation. Dr. Drinker rendered a report to us in June of 1924, in which he stated that there was indication of a hazard existing in our plant, the cause of which he could not definitely establish, but that in view of being unable to ascribe this hazard to any particular condition in connection with the manufacture or application of luminous material, he felt that we should regard radium with suspicion, and recommended certain precautions. We did not entirely agree with Dr. Drinker in his conclusions, which were based on negative evidence.