Acute Accidental Inhalation of U

The intake and deposition of U in three men accidentally exposed to soluble natural U compounds in an explosion in 1944 were reevaluated 38 y later by the U.S. Uranium Registry. The initial lung depositions were estimated to be about 40-50 mg of U based on the fragmentary urinary excretion data obtained shortly after the accident. The initial long-term bone deposition was estimated from individual excretion curves and was 410 micrograms (5.2 Bq) in the highest exposed individual, which resulted in an integrated 40-y dose equivalent to the bone surfaces approximately 2 mSv (200 mrem). Medical and health physics examinations of two of the men 38 y after the accident revealed no detectable deposition of U nor any physical findings attributable to U exposure. One of the exposed individuals showed an altered clearance pattern for U shortly after the accident, possibly from pulmonary edema associated with concomitant exposure to acid fumes.