The U.S. Transuranium Registry report on the 241Am content of a whole body

An analysis and evaluation of 241Am in the whole body of a donor to the U.S. Transuranium Registry (USTR) is presented in five parts. The USTR donor's pertinent medical history, autopsy findings and antemortem evaluations of intake and systemic burden are described in Parts I and II. The donor was a 49-yr-old male Caucasian radiochemist who died of metastic melanoma in 1979. His work with actinide elements began in 1952, and the greatest potential for intake of 241Am was when he used an unsealed 241Am source in his doctoral research (1952-54). The first indication that an intake had occurred was the detection of 241Am in a urine sample collected in 1958 as part of an internal dosimetry surveillance program. In-vivo estimates of the initial 241Am intake, based on sporadic urine samples and three sets of external photon measurements, ranged from 0.23-1.1 muCi depending on the calculational models and calibration factors used. No chelation therapy was applied. The time of intake was estimated to be approximately 25 yr before death. External photon measurements made on the donor's body and dissected bones, presented in Part III, have yielded new and more accurate calibration factors for external in-vivo measurement of the 60-keV gamma rays of 241Am and the 13.2- and 14-keV x rays of 239Pu and 238Pu. The symmetrical distribution of 241Am in the bones of the right and left sides of the body and the reliability of total skeletal 241Am estimated from external measurements of 241Am in the head were confirmed. The soft tissues and about one-half of the skeleton were weighed wet, ashed, reweighed and analyzed radiochemically for 241Am, as described in Part IV. The measured total 241Am in the body was 147.4 nCi, distributed as follows: soft tissues of left hand, 1.9%; liver, 6.3%; respiratory tract tissues, 1.5%; other organs, 0.9%; combined structural soft tissues (muscle, skin, connective tissue), 8.6%; mineralized tissues (bones, teeth), 80%. The expectations of similar 241Am concentrations in bones of grossly similar structure and also in parts of bones of similar microscopic structure were confirmed.(ABSTRACT TRUNCATED AT 400 WORDS)