The USTR’s first whole body donor was a research chemist who had inhaled 241Am during his graduate research1. The Dosimetry Subcommittee of the Advisory Committee and several collaborating scientists helped the USTR’s small staff to process this case2. Methodologies and techniques were developed to evaluate samples from this and future whole body donations.
The first indication of an intake was in 1958, when positive alpha counts were detected in a routine urine sample. These counts were later determined to be from 241Am. There was no documented event to establish the time of exposure, but it is likely that the intake occurred between March 1952 and March 1954. During this time the registrant reportedly manipulated 3-4 mg quantities of 241Am as a part of his graduate research at University of California Radiation Laboratory – Berkeley. The route of intake was initially assumed to be a single inhalation with a possibility of ingestion, but post-mortem radiochemistry results indicate that the soft tissues of the left hand contained 1.9% of the total body 241Am content1. Thus a wound was likely involved.
Between 1958 and 1976, 19 urine samples and 2 fecal samples were analyzed. A single dose of Ca-EDTA was administered in 1958. Eight skeletal in-vivo counts and one lung count were conducted in the 16-year period between 1962 and 1978.
Autopsy and Pathology
This registrant died in 1979, at age 49 y, from a metastatic malignant melanoma3.
Case 0102 Anthropomorphic Phantom
Half of the USTUR 0102 skeleton was radiochemically analyzed, and the other half was encased in tissue equivalent plastic as a unique anthropomorphic phantom for calibrating whole body counting systems. This USTUR 241Am phantom consists of a left arm, a left leg, a skull, and a chest/torso phantom. Half of the skull contains bone from the USTUR 0102 skeleton and the other half contains unlabeled bone from a different cadaver. Likewise, half of the chest/torso phantom contains case 102 bone and half contains unlabeled bone. DOE practicum student Deanna Hasenauer initiated ‘virtual phantom’ modeling of selected USTUR whole body cases by CT-scanning the case 102 241Am phantom.
October 1985 Journal of Health Physics
The entire October 1985 issue of the Journal of Health Physics was devoted to a report on USTUR Case 102. Five papers discussed the case history3, initial systemic burden1, gamma-ray measurements4, preparation and analysis of the tissues and bones5, and implications for metabolic modeling6. McInroy et al. detailed the radiochemical analysis and results, and Durbin and Schmidt developed an Am metabolic model.
The Durbin and Schmidt model consisted of six tissue compartments: two soft tissue compartments (ST1 and ST2), a rapid turnover bone compartment (BF), a slow turnover bone compartment (BS), the liver (L), and a transfer compartment – plasma (P)6. Urinary excretion (EU) and fecal excretion (EF) pathways were also included in the model. This model along with the other papers published the 1985 issue of the Journal of Health Physics contributed significantly to our understanding of americium biokinetics in man.
Contemporary Burden Estimates
In 1978, the Lawrence Livermore Laboratory estimated the registrant’s skeletal burden to be 130 nCi. The analysis was performed using the AERIN code and urine data.
- Heid, K. R., Robinson, B. Part II: Estimate of the initial systemic burden. Health Phys. 49: 569-575;1985.
- Kathren, R. L., Harwick L. A., Toohey, R. E., Russell J. J., Filipy, R. E., Dietert, S. E., Hunacek M. M., Hall, C. A. Annual Report of the United States Transuranium and Uranium Registries: April 1992 – September 1993. USTUR-0015-94. [full-text]
- Breitenstein, B. D., Newton, C. E., Norris, H. T. Part I: Introduction and history of the case. Health Phys. 49: 565-567; 1985.
- Palmer, H. E., Spitz, H. B., Rieksts, G. A. Part III: Gamma-ray measurements. 49: 577-586; 1985.
- McInroy, J. F., Boyd, H. A., Eutsler, B. C., Romero, D. Part IV: Preparation and analysis of the tissues and bones. Health Phys. 49: 587-621; 1985.
- Durbin, P. W., Schmidt, C. T. Part V: Implications for metabolic modelling. 49: 623-661; 1985.