Merril “isenbud, Director Health and Safety Laboratory Roy E. Albert, M. D., Medical Officer Health and Safety Laboratory MINUTLS OF STRONTIUM MCTABOLISH MEETING AT THE WASHINGTON DIVISION © ~BIOLNGY AND 4EDIGINS, WEDNESDAY-JANUAZY 13, 195. SYMBOL: 4S: REA Q-Z7 DATE DATE - Approximately 25 paople attended this conference and the chairmanship as civided betweon Drs. Bugher and Claus. The purpose of the meeting as to discuss the current concept of tolerable strontium burden and also the status of information on strontium metabolism in relationship to the tolerable burden in persons exposed to fallout material. Dr. Brues opened the discussion and distributed a set of notes cover- . ei frowy * lson_1l-/=¥¥. CLASSIFICATION CANCELLED BY AUTHORITY OF DOE/OC BEST COPY AVAILABLE ing the pertinent details on strontium and radium toxicity in humans ¢ ABAbe and animals. He mentioned the study currently in progress at Argonne a son the long-term follow-up of individuals who received radium for “a@therapeutic purposes. On the basis of this study and others on radium eeetal painters, the permissible burden of 0.1 uc still seems like a &: zood mumber. He quoted Zvans as saying that those cases with less than Le 1 microgram of radium bedy burden and with bone changes probably were exposed to mesothorium originally. The mesothorium is more toxic than radium because thoron is not released from the body. radium retention is about 1% of the initial dose. fhe long-term One year after exposure, the retention was shout l% so that the integrated dose is about 2 times the long-term body burden, Dr. Brues ia also carrying out a study on the radium burden of inmates in the Joliet Prison who have been drinking water containing 5 uuc/liter, The body burdens of these individuals 4s at least 10°3 microcuries. ‘There are a number of cities in [llincis whose water contains the above concentration of radium and studies are now under way to eatimate the incidence of bone sarcoma in this population. The Aurora Hospital has about 1 hone sarcoma ver year for a population of about 30,000. to be excessively high. This does not seen Mouse studies were discussed indicating that the comparative carcinogenicity of strontium to radium is from 1:8 to 1:15. These studies were done on a type of mouse which has a high susceptibility to benign tumors. It is not known whether the high incidence of malignant tunors represented only a conversion of benign tumors to a malignant form, There is evidence that the latent veriod in the development of cancer is a function of life span in amimals. The bone changes seen in humans following ingestion of radium seem to progress very rapidly after they once become apparent, also sucgesting a latent veriod. DO PP TH, gu seae DO ARCHIVES