Substantial adsorption of Pu, Cd and Pb onto mouth surfaces of mice occurs during consumption of drinking water that contains these elements. If this adsorption is not taken into account, the amounts deposited in the eviscerated carcass (muscle plus skeleton) after gastrointestinal absorption are overestimated by 2-9 times for the experiments described. An evaluation of data indicate that significant adsorption can also occur during gavage administration. Methods are described for estimation of amounts deposited in the carcass after exposure of mice to these metals via drinking water or gavage.

The concentration of plutonium has been determined along the length of the hair of a female subject who received 11 kBq (0.3 pCi) of 239Pu by intravenous injection in 1945. The subject succumbed to her pre-existing illnesses 518 days post injection, and her remains were exhumed in 1973.The subject's hair, 280 mm in length for the longest strands, was divided into 20-mm long sections and the plutonium concentration in each was determined. The concentration ranged from 22 Bq/kg (0.59 pCilg) at the distal end to 3 Bqlkg (0.08 pCi/g) at the proximal end (nearest the scalp). The distance of each section from the scalp was then converted to an estimated time in days post injection by applying the growth rate of the hair indicated for this individual.The plutonium concentration as a function of time could be well-fitted (in the least-squares sense) by either of two functions. The first function was the sum of a single exponential, whose half-time was 81 f 16 days, plus a constant term. This half-time corresponded to that found for the longest-lived of five components of the plutonium concentration in the blood of other individuals in the same series of injections, i.e. 88 2 13 days (Du72). The second function which fitted the hair data was the sum of two exponentials, whose half-times were 32 k 18 and 260 f 80 days, respectively. These values overlap the half-times of 42 and 300 days found for components of the urinary excretion of plutonium by man (Du72). This agreement is expected in view of the correspondence of the hair and blood data, since urine is a plasma filtrate. The possible use of hair as a bioassay material for plutonium in man is suggested.