In vivo measurement of 241Am in an accidentally exposed subject

Detailed external measurements were made of internally deposited 241Am in a nuclear chemical operator involved in an americium exposure accident at the Hanford plant. Despite some interference from high-level external contamination, quantitative measurements of the 241Am content in the lung, liver, and bones were made starting on the third day after the accident. The rate of excretion of 241Am from these organs was determined. The 241Am embedded in the skin of the face and head was carefully mapped. The distribution over the total length of the body was also determined. Linear and rectilinear scanners, gamma cameras, large and small scintillation detectors, proportional counters, and Si(Li) and intrinsic germanium detectors were used to evaluate the internal deposition. Methods of calibration for quantitative measurement included simulation of the 241Am activity in both phantom and cadaver parts