Clinical Methods - the Excretion of Uranyl Nitrate Given Intravenously to Man (Draft)

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chemical hazard, and it is along these l i n e s that the present experiments have been directed. While uranium compounds are higlily poiaonous when they gain access t o the circulation, there is little reason to fear that serious toxicce qo sure s will occur during the ordinary course of indus4rblsctitiitbs. Uranium salts a r e absorbed poorly when ingesteit and unless there is gross carelessness, the inhalation of contaminated dust can be controlled readily. ,q?'*It is possible; however, tht long continued -sure to the dust of concentrates of U2J4, U235 may, because o f .more intensive alsha emission, tea radiological hazard particularly for lung and bone. ium forns complexes with bb ' and whin given in amounts, is bicarbonate. A fraction of the fixed t o the phosphate groups of 10 to 20 per cent, becomes [ aCG < G e - o f the manner of its elimination, the chief toxicity of uranium is for I t has been found recently that urinary catalase and _o f uranyl acetate given is well below the level that will produce gross symptoms of uranium roperted f o r some workers in uranium =,,.ftudo.- Obviously i t is of Interest to

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determine whether man w i l l react with catalasuria and proteinuria- to such small quantities of,uranim. From animal studies w e find j nY-casing degrees of tolerance; the moat susceptible animal that has been investigated is the rabbit,"while. the toxic effects of uranium are produced lesa readily is the cat, dog, and rat in approximately the order mentioned. we have been able to carry through toxicity for adult hunians&is more nearly the order of that for the rat and suggests that genus homo occupies a position in the more resistant group of The experiments which that the chemical 11. Qose of Experiment 4 )&&& ! The investigation waa undertaken with these objectives in mind, A. . To find that dose of a soluble uranium salt which, when introduced intravenously as a single dose, would produce j u s t detectable renal bjurY. 'e bjurinar;. protein; ratio o f amino nitrogen t o creatinine nitrogen in the urine, gl ome dar filtration (mannitol), red plasma flow, maximum t.Jbdar excretory ' ~ o tall of the more complicated.tests o f renal function were done in every patient; however, urinary catalase and protein which are very sensitive indicators o f renal injury were followed carefully i n each case. B o To measure the rate at which soluble uranium compounds are eliminated from the hunan body once they have entered t h e circuletion. Both urine and fecal specimens were obtained from the erperimental subjects, "rim w a s collected in individual

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negligible and the fecal analyses were discontinued. C. To observe the e f f e c t of measures aimed at increasing or decreasing the rate of excretion of uranium. Three experiments of th io qat ure were performed. Mobil+tion of the small fraction of the dose which was apparently retained was not affected, by the intravenous administration of citrate, nor by placin$ one of the subjects on a low calcium diet together with large doses of A.Tl0.* Production o f an acidosis with ammonium chloride, on the other hand, clearly delayed the excretion o f uranium i n the urine. The details of these'experiments appear in 111. Selection o f Subjects and Size o f Dose. The experimental subjects were chosen from a large group of hospital patients. Criteria of inportance Fn making the selection were reasonably good klL7e:- fx ct ioc with urine free from protein and withe nom21 sediment on clinic de mim tion. The probability that the patient would benefit from continued b spit aliz ation and medicel care uas also e factor i n the choice. 'dheri kigher levels of dosage were contemplated, individuals from the older age groc?s were preferred iaview of the remote possibility that late radiation m e iritial dose was set et approxinately 6 w.o f the metal per kilo o f body weight and was chosen because this is the mount which will occasionally produce just aetectablefiena of injury to the kidney were detected. Until i t was established that the rate damage in the rabbit, a highly susceptible The plan d leC for a slowly increasing dosage provided that no signs of and totel excretion were o f the sape order as that f o r experinental animals, no subject received more than a single dose. When the amount given approached 50 m c - &. per kilo, the enriched mixture of isotopes of U2j4, U235 was diluted

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1 - 4 using uranyl acetate of the ordinary that this would decrease the radioactivity effects would be higlily improbablp. isotopic h6.It was estimated to a point where any late radiation Subject.& -reaeived the l a r g e s t amount of uranium, about 71 mc. gm. per kilo and wata given a second injection after acidification with amnonium chloride. Ho renal toxic action was noted.. IV. Nature o f Material and Technique of Administration. Portions o f the sample of uranium oxide (U30p) enriched i n n234 and described in PatI of this report were weighed out and used in the preFaration o f sdlutions o f uranyl nitrate for intravenous injection. When the subject had been selected and the s i z e of the 'dose agreed upon, enough of the +-nim nitrate solution t o contain several times the quantity o f metal required was diluted witha 1.15 per cent solution of sodium acetate, the pH dilution was arranged so that the qu act it iy of uranium t o be injected would be buffered uraniun salt was trensferred p&Ic~11;1 to a sterile rubber capped After autoclaving toe sure sterility about 20 ml. o f the vhl.TrUl analyses were run on the remaining solution by the method of plating and alpha counting t o serve as a check on the accuracy o f the initial weighing and 6ilution. If the amount of uranium present as calculated from theee two procedure6 vas found to be in agreement, the sterile solution was considered ready for use. -the viql into a 10 m l . all-glass syringe and the needle removed. The syringe i was handed t o an aes is tant and held so that none of the contents would escape.

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A number 20 needle attached to another syringe partly filled with physiological saline was used to cannulate the median basil ic vein of the patient and enough saline injected t o insure that none o f the liquid was leaking into the adjacent tissues. - llhe needle was l e f t in place and the spinge containfng_the.sohtipn . - of uranium was attached. A few drops of blood were drawn into the barrel to indicate the continued patency of the needle and the injection was made promptly. The syringe was rinsed once by withdrawing the plunger elowly u n t i l blood reached the mark of the previous f i l l i n g , and the blood was reinjected into the vein. &e same syringe used for the injection wagcleaned and dried. The solution of uranium was again drawn from the vial to the proper mark and the needle removed. A second 20 gmge needle filled vith water was attached and the solution ejected through it into a 200 ml. volumetric flask. Water was' now Cram through the needle into the syringe to the s m e volume a s that of the ?repared from the solution used for the injection. The average value of the uranim n e t a l found on analysis of the two dummy solutions was taken a s the mount iijected. As arule, these did not differ from each other by more then 5 per cent. This was sufficiently good agrement for the purpose of the clinical Four male a n & two female -patients were studied. A resume of the experimental work appears i n table 1. designated/A)prior to taking ammonium chloride. about g gin. of ammonium chloride daily for three days and then 1 2 @. daily for Subject f 6 received the uranium in the experiment I n experiment [B\he was given The C02 content o f t h e serum decreased from 64 volumes per cent to

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32 volumes per cent. He received the second Injection of +6 uranium seventeen days after the first dose and when 90 per cent of the latter had been excreted. !be effect on the r a t e of excretion is seen b e s t on inspection of Figure 1. The production of acidosis in man decreases the cp4od of excretion of uranium 5n the urine just as it does in the rabbit a\>. Excretion of Intravenously Administered Hexavalent Uranium. Details . valent uranium vkre carried out by the methods f o r plating and alpha count-/’- . described in Part I of t h i s found that when the metal cwas g ven--. i.v., l i t t l e could be recovered in the feces, while the major portion v a s excreted rather promptly in the urine. appeared f r o @ the blood stream very rapidly. While we have no positive information on t h i s point, ,dLal experiments suggest that it becomes fixed in the kidney ad and particularly in the bone and that .It i e slowly releaeed from the l a t t e r : Tne injected uranium also di6 (1) The details of the hunan experiments are as follows: I n hospital because of rheumat id-- arthritis and uretheral strictures. A t the time o f study his disease was quiescent. The urine contained neither Protein nor casts and the catalase activity was low. Control analyses of urine d e and feces did not disclose the greaence of uranium. On S/9/46 he was given 385 x-c py o f uranium metal. intravenously a s the nitrate diibuted to5 ml. with sodiun a ceb te buffer. . Collections o f urine end fecee were started immediately. Blooc! was drawn four hours l a t e r and found to be without detectable alpha activity. The. pertinent clinical :.laboratory data areto be found in table 2. %bles 3 and 4 present the values found on analyses of urine and feces repective- -i

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Daily tests of afresh specimen o f urine did not reveal increased catalase activity in the post injection period; there was no proteinurfa; the ratio of amino l?/Cretafnine lV did not show a significant variation from the control wlaes/as may be seen from table 2 urea clearance, blood counts and blood . __ chemiatrp were not affected by the injection. I n summary the intravenous Injection of hexavalent uranium prepered from a mixture of isotopes enriched in $3!, U235 at a level of 6.3 per kilogrm did not yroduce demonstrable renal W g e . +/ Hospitalization w&6 required because of acute alcohobism, hdlucinatorY State, cirrhosis of the If-r with cmgestive splenonegaly and a neuropathy probably due t o deficiency o f the --*itamin B cosplex. A t the tine of this study the more acate symptoms bad subsided and while still a bed patient, she was able t o give adequate coogemtion in the collection of specinens. U235 shi lar ’Ln composition t o thet received by Subject No. 1. In this in skn ce the 2ose w a s equivzlent to 476.7 netal an5 was contained in ‘f y f l ‘ Collections o f urine were begun imnediately but the feces were not saved. Clinical laboretory bta and the results of analyses of the urine for anim nitrogen to creatinine nitrogen i n the ube before and after the uranium Table 7 gives the rz tio s obsened for A s in tne first petien* the excretion o f U6 in urine was veryrapid during the first twenty-four hours x i ? accounted for g4 per cent o f the amount givan. The t o t a l excretion by thi6 route wa6 87 per cent at the end of six days. Again there was no increase i n - criIL ? rjrc ~ talas eor protein or other indication

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This young woman was ic fairly good physical condition excegt for mild chronic undernutrition which was thought: t o be secondary to an emotional mal- 'ive ml. of acetate buffer containing uranium nitrate equivalent t o 584 mc. gu. of the net al in the fonn o f the enriched mixture o f is&pes of u234 and U235 was- injected into an arm vein on October 1, 19%. This dose reprbsented 15.5 Urine and feces were analyzed for uranium 'both by tho flUu+=ssr;cYSCt wcbbd of Eelimnrln 0% dluz by the electroplating and alpha countiag method. The quantity o f uranium excreted in the feces was too d l to measure accurately and no tabulation o f the results is shown. Table 8 gives the urine values obtained by the 21;3hz cauilting method. The excretion a?;leared to b e somewhat less complete follower;, the usual pattern. The clinical tests are recorded in table 9 and the Although the close o f uranium on a kilo gr m basis had been @ore than doubled, there was no increase in urhry catalase o r ? rot & i n ; the r enal clearances remained unchanged an^! the u in arya in o nitrogen/creatinine nitrogen ratio .Entered hosptial because of cfironic alcoholisn and bleeding from the estr a intestinal tract. His acute s pq toms subsided after ten days and he wa8 transferret! to the Metabolism Unit. Stools continued t o show positive tests -f o r occult blood fora week but were normal thereafter. bzrium sulphate o f the espphagus, stomach and intestinal tract wbre negative

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exceFt for coarse gastric and upFer small bowel \nucod. patterns. The urine was normal. However, during t e s t s of urea clearpllces, the Tatient experienced diff3;cult- i n voiding at the tines requested, urethral stricture or enlargement of a e prostrate as a contributing factor. Y f There was no evidence of Type o f Clearance Per cent o f Bormal The reduction ofnurea clearance was not felt to bea contraindication to continumce-of the experiment, for the urine was normal to cl in cia l examination and b2d e low catalse activity. The injection of +b uranium was given on In t h i s case equal ?arts of the enriched isotopic nixture and of the net1.x-d mixture o f isotopes were given. The total dose o f uraniun netal Table I1 gives the excretion o f uranium i n the urine aod = t ~ ~ ulsre dW tro - No significant m o u n t of uranium could be detected in the feces. It is to b e no tea that the rate and percentage

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excretion was m u c h the …