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o f plutonium in them were about 100 times lowcr thiln those in bone. 'I'hc subject's hair. 2 x 0 niin in Icnglh for ils longest strands, appeared to be intact and in good condition. Since the analysis of trace clcnients in hair is one method of determining exposure to toxic materials (e.g. Ja78). i t was decidcd to meiisure the plutonium concentration along the length of the hair, and to compare the results with the concentrations o f plutonium in blood and urine observed in The subject's hair was removed from the remains with the scalp intact. It was dried at I(H)"C for 48 hr and then cut away from the scalp as closely as possible. The hair was washed with a detergent solution until microscopic examination showed it to be free of foreign matter; it was then rinsed with water and air-dried. Because of the presence of small bits of tissue in the wash solution it was impossible to determine if any plutonium in the solution had been leached from the hair. However, there is no reason to suspect that the mild detergent used and distilled water could in fact have leached plutonium from the hair strands. The longest strands measured 280mm and we defined the parameter d as the distance of any portion of the hair from the scalp. The hair strands were cut into 20-mm long sections. beginning at the proximal ends. Sections with the same value of d were combined. weighed and then ilnalyzed as a single sample. The plutonium content of each section was tion. The hair samples were dissolved in nitric acid. il known amount of z42Puand an excess of 9 M hydrobromic acid were then added and the solution was evaporated to incipient dryness. The procedure ensured isotopic exchange between the '"Pu that was in the hair and the isotopic diluent, '"Pu. The plutonium was sepiir;lted from the solution with the anion exchange procedure of Larsen iind Oldham (La7S); it was electrodeposited on ;I stainless steel planchet with the rechniqiic reported by Kressin (Kr77). and the dcposit was ;issiiyed in a n a-spectrometer. The plutonium recovery ranged from 70 to z4zPupeilks in the series ranged from approx. The results are given in Table I . The plutonium concentration is expressed as 0.027 pCi/g). The plutonium concentration shows a steady increase with distance from the scalp. except for a few fluctuations which are not statically significant, and for the data point nearest the scalp itself. The concentration of plutonium in the scalp was determined to he 210 Bq/kg. The very Iirrge value of plutonium concentration in the hair section nearest the scalp may be due either to crosscontamination during the drying and removal of the hair from the scalp, or possibly to adsorption during the 26 yr of interment. Since there is no known physiological reason for the large value. this data point hits been omitted from the subsequent analysis. It must be noted that our choice of d as a parameter requires the assumption that the growth rate of the hair was uniform over the entire scalp. There does not, however, appear to be any smearing of the data as would be expected if the combined sections contained hair that was formed at different times. Consequently the assumption of uniform growth rate over the scalp seems justified.
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intercepts or hiilf-times of the two components ohserved in her urinary excretion pirctl with thc wiiic conipi)ncnt\ in c ; i w s with her litter components. even though not observed in the urine Jiitil of 40-010 (last \iimple collected on day 27 post injection). would ;dso be expected to agree with those for the normid cases in Table 2. The half-times of the two components fitted to the hair data (equation 2). equal to 3 2 % 18 and 260 5 80 days, overlap UT, and UT,. nilmely 42 and 300 days. within error. This agreement between the time dependences of the hair and urine data is not surprising in view of the correspondence betwen the hair and blood data. since urine is a However. the relative magnitudes of the two components are quite different in the hair data vs the urine curve. From equation (2). the riltio of the intercepts is 1.7 :0.8. while agreement may possibly be explained by the medical status of this individual. involving both nephropathy and hypertrichosis. Since urine and hair are both routes of excretion far plutonium in the blood. the time dependence of each should reflect the time dependence of the blood content. as observed. The relative efficiency of each in removing plutonium from the blood may well have changed in time in this individual, as her disease progressed. Thus the relative magnitude of the two components could vary with excretion route. while the time dependence remains the same. I t should he noted [hilt the two major assumptions involved in the analysis of the hair dat;r. namely that the growth rate W i i s constant over the scillp and that the distal portion of the longest hair was formed close to the time of injection. are both supported hy t h e consistency of the hitir diitil with the blood and urine data. The correspondence of thc hair ;ind blood d;it;i is further strengthcncd by consideriition of UT, and UT,. I f the s u m of these conponents of the urinary excretion curve is iiniilyzed i1s ;I single exponential from 0 to 300 days post injection, it exhihits a half-time of 92 days. essentially identical to BT5. This annIysis of two components as one explains the fact that equation (2) is a slightly better fit to the hair data than is equation ( I ) . The constant term in equation (I) then, which does riot correspond directly to any component of the blood curve, very probably reflects the appearance of that component of the plutonium concentration in the blood which gives rise to the fifth component of the urine curve. with UT5-= 4000 days. If we pursue the correspondence between equation ( I ) and the fifth component of the normal blood curve, the concentration ratio of plutonium in hair to plutonium in blood can be determined by comparing the intercepts of the exponentials. Langham assumed that the total mass of blood was equal to 7.7% of the body mass (La5O). For this subject, with a body mass of 55.5 kg, the initial concentration in blood would have been I I kBq per 4.28kg of blood, or 2.5 kBq/kg. ponent (BS5) would have been 0.44% of this. or 11.3 Bq/kg. The fitted concentration in hair was 18.2 Bqlkg, and therefore, the concentration ratio was 1.6. The concentration ratio between the hair and urine can be determined by comparing the intercepts of equation (2) and US, and US,. USI=0.013% of the injected dose per day, or 1.43 Bq/day. If the average urinary output is titken ;IS IOtMml/d with ii specific gravity of 1.02 (ICRP75). then the concentration of plutonium in urine was 1.4 Bqlkg. Since the intercept of the first component of equiltion (2) is 17.5 Bq/kg. the concentration riltio is 12.5. Similarly, for the second component of equiltion (2) and US, the concen- [ration ratio is 31.2. As mentioned above. this chiinge in concentration ratio may be nttrihiited to the illnesses of this subject. Kcgardless of the discrep;rncies in the irhovc ;in;ilysis. i t nevertheless raises the intriguing possibility that human hiiir may serve