JFFICIAL USE ONL. external counting of the radiation emitted by the americium which is normally a contaminant of plutonium, The weak x-rays emitted by plutonium can also be measured by using a thin cesium crystal glued to a large sodium iodide crystal. Anticoincidence counting gets around the problem of the background and provides a sensitive test. Presently intercomparisons are being made by all the various laboratories that are doing external counting. Dr. Wood pointed out that germanium detectors show a great deal of promise for external counting but as yet they are not big enough to be particularly useful. He showed the committee an esophageal probe which can be inserted by mouth and which will detect plutonium deposited in the lymph nodes along the tracheal bronchial chain. The sensitivity is estimated at perhaps 10 nanocuries. Another new development is a wound probe which uses a silicon avalanche detector. In many respects it is similar to the esophageal probe. Dr. Edington, Chief of the DBM Biology Branch, reported on the proposal of Dr. Neel, from the University of Michigan, to make further genetic studies at the Atomic Bomb Casualty Commission. Briefly, Neel is proposing to use new techniques to examine the serum of the F, generation in Japan. By examining the serum for certain isosymes, he may be able to estimate the number of biochemical mutants induced by the radiation exposure to the parents, The early studies that were done by Neel and Schull necessarily used somewhat cruder endpoints. Dr. Dunham, from the National Academy of Sciences, Dr. Neel, Dr. Edington, and Mr. Whitnah from the DBM staff recently visited Japan to explore the possibility of initiating these studies. The Advisory Committee to the NAS for ABCC last spring approved the proposed research. Approval is also required from the Japanese National Institute of Health before such work can be initiated. The JNIH approved a pilot study only, which would be limited to presently stored blood samples from the cytogenetic studies and any blood that is collected routinely for other purposes can also be used. There are approximately 1000 samples stored and the present rate of collection is about 1500 samples a year. Dr. Neel visited Kyoto University and the University of Tokyo as well as some other schools to talk especially with Japanese biochemists to try to interest them in the project. They seemed enthusiastic and would undoubtedly become involved in the study. A pilot program to conduct this research is presently being set up. About $50,000 from an existing contract with Dr. Neel will be used in FY-1972. They hope to have the equipment and three technicians ready to opeate by the first of July. Current budget thinking is for about $100,000 in FY-1973. By July 1974, they hope to have the approval to go into a full scale study. Dr. Bruner, Assistant Director of DBM, reported briefly on the Second White House Conference on Aging. The Committee then went into executive session. Dr. Burr reported that the article in the November 5, 1971, issue of Science concerning Rocky Flats had distressed the Commission. The matter was discussed with Dr. Larson, of the Commission. Drs. Bair and Goldstein outlined a couple of possible articles on plutonium which might be written and published in - 10 - OFFICIAL USE ONLY