Letters Sent to Arthur Roeder [A. Roeder], July 14, 1924

002X Harvard University School of Public Health 55 Van Dyke Street, Boston, Massachusetts. July 14, 1924. lir. Arthur Roeder, United States Radivm Corporation, 30 Church Street, New Yorl City. My dear lir. Roeder: Inspection of the wrok done with oux animols lends me to feel that further delay in reporting upon them will give us no more information. On liny 13th tre gave intratracheal injections of luminous zine sulphide to one eat and of "Undark to throe cats. The reason for this method of administration is because it assures a prompter and more efficient absorption of the substance used, and is, furthernore, similar to one of the routes by which your employees telte in these substances. In no case did we gain evidence of any local damage to the lungs. After one to four weeks! time we sacrifieed the animols, and found no noteworthy abnormalities at eutopsy. Upon chamical analysis, the bonos of the cats receiving "Undark" contained large amounts of radivun - more than tre could obtain from the lungs, the site of the original deposition, or from all the rest of the body. Our apparatus does not permit the giving of a quantitative figure on this-point, but it has established very definitely that inholed "Undark is removed from the lungs and the radium carried by it"is deposited in bone. In both the luminous zine sulphide and "Undark" animals the skeleton contained some zinc, deposited apparently as a double phosphate in the compact bone, and being analogous in this particular to lead and a number of other heavy motals, though probably less permanent. On perusal of our report, you will note that we cited abundant evidence from the literature to the effect that intravenously or shbcutaneously injected radium proparations deposited radium in largo amounts in bone. We felt it desirable to find out thether radiun introduced by inhalation, as "Undark", is deposited in the same way. This has been definitely established by these experinents. To you, I suppose, they will seem unnecessary, but we feel that they bring out in rather a bohd relief the fact that rodium administered as it slowly is to your employees, readhes bone. You will ask why, if wä have dono this, we have not gone on to the question of necrosis production, thereby clinching matters. If this phase of the situation could be established experinentally, it would require a considerable series of animals dosed over a long period of timo in sevoral