i nev UNCLASSIFI6n enployees entering the Laboratory and the gradual addition of piood typing of the old emplovess, with setting up of a file of the arions blood types and RH factors. This profect may be looked upon as a etep in connection with civil defense, fr, Resesres Projects In the autumn of 1949 the Group began 4 research project to stud; the metabolism of trinitrotoluene in the animal body using Carben|4 leveled TNT. In the past year much of thie work has been completed and the results vere presented at the meeting of the Laboratory Dirertors and Industrial Physicians, which was held at Los Alamos during the latter part of September. To date it han been shown that 60% of all the crally administered dose of TNT to a rat is absorbed in twerttyfour hours and 90% of the amount absorbed is excreted in the urine. There appears to be little accumulation of the material within the animal kody with the largest amounts (less than 2%) found in the liver, kidney, and skin, In general material given ty the oral route was rapidly extreted. In addition it was found that dry TNT applied to trea skin was repidly absorbed and excreted. The amount absorbed roughly proportional to the area to which the material was applied. In addition it was noted that a number of the so-called barrier c do not prevent the absorption tit rather appear to facilitete it. finding is of considerable practical importance in that it demonstrmtes that the skin is probably the mein route of absorption of the natemial into the worker's system, at least in the operations performed her - 35 - Womens 0MSIIED POuKuT2 00130915 037 LANL