Document ykdepp3gez5K7oM6w3M0DwnXd

THE JOURNAL OF 'rf..,.n- %. INDUSTRIAL HYGIENE i -a .&.. --5qe- ..--a. y o m 26 P AND TOXICOLOGY 4 49- 7 MARCH, 1944 N-ER 3 c -Y' .7+7'-s. TrJDSES ON THE INHALATION OF 1:3-BUTADIENE; WITH A COMPARISON 1. OF ITS NARCOTIC EFFECT WITH BENZOL, TOLGOL, AXD STYRESE, AND A NOTE ON THE ELIMIXATION OF S T Y R E N E BY THE HU3lA.P dm,".%----pisT--- CEEABLEs P. C. BOYD SHAFPEB,C-OL S. VEIL L - M D & m y F. S Y Y ~J ,R . ~ -:r J f d h Insiilu!e, Piusbwglr, Pa. HE extensive use of butadiene in the manu- daily anesthetization of rabbits with butadiene, -*- facture of synthetic rubber has stimulated and investigation of thc psycho-motor responses -:m theinvestigation of its physiological properview of the notable lack of information on of humans to butadiene, toluol, and styrene. Full protocols appeared in a mimeographed report to , Trb: subject. Von Oettingen, in reviewing the the Rubber Reserve Co. , & d u e on this hydrocarbon, gives references.to The butadiene used was obtained from the =(u.L&.* ?>%-.nacatic action upon mice, rabbits, and man Carbide and Carbon ChemicalsC o r p o a t i o ~The The statemeat is made that in humans the drst 100.lb. cylinder was delivered in June, 1942, "'mhabtion of one per cent vapors of butadiene for and iepresented butadiene reclaimed from the 5 minutes caused no other eflects on the blood cracking of butane. Seven hditional cylinders -. mure or respiration than a quicktning of the containing SO0 Ibs. of the same grade of butadiene pike, together with a slight feelingof prickling and mere received in August, 1942. When the present dryness in the mouth and nose. S o other pub- investigationhad been nearly completed butadiene lirhed articles pertaining to the efied of butadiene made commercially by other processes became a0 animals or man have been noted. available. X o toxicological study of other sam- l:SButadiene, C& is an unsaturated hydro- ples was undertaken, however, because it is judged n, which at m m temperature is a colorless matic odor. Its molecular weight and it boils at -4.7% at 760 mm. of The explosive limits in air are 2.0 to that the results set forth here apply equally to butadienes suitable for polymerization, no matter what their source. This andusion is sound be- ant by volume (2). paper reports upon daily exposnre of ani- to batadiurc for 8 months, determination of n d c i e n t of butadiene between a comparison of the -tic action benzol, and toluol upaa labbits, -- L 70 JOGFCXIL OF EIDUSTRLU. HYGIESE .WD TOXICOLOGY [mi. 26, no. 3 about 200C., iodine p t o r i d e completely oxidizes and capillary tbwmeter, and added to the dilution butadiene with the liberation of 2.2 rnolecrilcs of alr being drawn into the chamber from the room. iodine for each molecule of butadiene. By col- The highest conantration used for repeated ex- lecting the liberated iodine and titrating it with posure approximated one-third of the lower a. sodium t%iosulfatc, the amount of btitadiene plosive limit. It is thought that prolonged human acting upon the pentoxide may be determind. v u e in industry cannot exceed this value The procedure does not ditru ersentially from because of nmssary prrcautions against fire. that used in the estimation of ethyl ether (3). A total of 164 aniuaah inhaled butadiene vapors m i l e a variety of organic vapors will react with 71 houn per day, 6 days a week for 8 m o n k iodine pentoxide at high t c m p t u r e s , the pro- Gmupr of 24 albino rats, 12 guinea pigs, 4 rabbi9 cedure is admirably suited for the quantitative and one dog inhaled flowing butadi&e-air mu- determination of any one of them, pmvided, as in tures averaging 600,2300, and 6700 ppm., I t s this casc,othea are known to be absent. controls exposed in a similar chamber to air alone. Samples of butadientair mix- were collected Sua were c q u d y distributed, except for the 4 over mercury either in d gwampling tubes os dogswhich wen dlf d e . T h e maximumnun- in gas burettes. Blood ~ampIeswere taken with ber of exposures given any animal was 202 within a syringe and hypodemic needle and immediately a period of 8 months. transferred to a 125 mL Ericumeycr flask fitted Preliminary weight stukes and blood counts with a rubber stopper partislly pedora+& so chat mere made as a basis for selecting normal healthy the needle could be f o d through it ncsdifp bat stack. The diet WBS Purina Rabbit Chow Entire which would a~tom;rticallyseal upon removal of Ration for the guinea pigs and rabbits with kale the needle. stoppa was also fitted with Met as an adjunct 3 times a week. The rats and dogs aad outlet arms ocdudcd by screw clamps so mere fed on Ruina Dog Chow with fresh bone that it could be p b ! d the iodinepentoxide trafn marrow and liver similarlyprwidal. F d water without any loss d butadiene A mcchanicd was avaiIable at dl times while animals were not shaker, to agitate the Erlcnmeya h k containing being erpssed to butadiene. The uposuns ofthe the blocd sample,was found to be acasaxy in control animalsparalleicd those of the test animals order to remove COmpIetcly the gas contained in in every way except that no butadiene \vas added the blood. Comparative tests indicated that ap- to the air stream p&g though rhcir chamber. proximately 26 per cent of the butadiene content During the COU~K of the exposum the conen- of the blood remained entapped in it where the tration in each of the chamben was estimated mechanical shaker was not wd. daily by means of a Zeii 50 an. portable intm TOcheck the w t ~ c iofi ~this ana~yticaimethod. ferometer. one scale division of which was found known amounts of butadiene were -taken d i i d y equivalent to 21.1 ppm.. of butadme. The iodine from the storage cylindn. With a gas sampling pentoxide method desaiied above was applied at tube of 5975 mL capadty the average recovery intervals to check the optical instrument. Each was99.spercentan3trials. Fiveothvtri& cylinder was analyzed forlmtadicnc,acctylenq with a very thin-ded sampling tabe of 2.925mL and aldehyde at the beginning and near the end capacity yielded rcaweties which averaged 96.28 of i u useful life. Weekly weight records wen per cent T h e latter tcsb were iduencui d u l y kept for allanimals and body-lengthnwsurrmmb by changes attniutnbte b variation in robfn tern- on rats were made monthly. At the tamhtim of cxpsurc, kidney and liva weights of Iats PlQI .. -:+ llsrrk 1w -& taken at death or pathological studies. *- GROWTE AM) GE FIt L inevitable that 5 o r g - r in =Y lruge gr &periods of time and I &no exception. About i ,fled werc omitted fro1 psuchiIlfcctions. Invie tit180 auimsls, including I&, was used on the chrc was not an unduly high ir pT6ere were no death could be attributed t The animals showed no c.their vigor or activity vis1 iDtin period they were ex ctpt insofat they deve &as. ~ h e r a t s r e c c i v e d t ! b o t 68 days. At this t: dthe 4 groups WenFract tamination of the urpontr 663,and 812 pet cmt of h,and 6700 pprn. amct liidy. Thesedatashowi &tc iduencc on the gr totlghly proportional to th diene. The final weights pigs indicated the nbbits were used to ma bprb of gmwth, and rabbi1 hthisrespect at best. 'I ucd in weight from wet e c e d , they were hcav. % 11.1, 8.0, and 14.7 pc a36e control, 600, 2300, a C'QtiOa 71 srcfc t&rn at dexk ar q c l n jacr:ricc ior histo- the rcsults usciul. The l i x r wight3 ior :he fiC0 '$&logical studies. and 2300 ppm. group are slightly lower than those G R O \ m i h?m CEMEIUL HWLTX i ;is~kvkable that some extraneous infections *&occur in any large p u p of animals kept for *bagperiodsof time and this study has proved to of the controls for a given body weight, but those of thc 6700 pprn. rats were normal. In view of the fact that the highest concentration compares favorably with the controls, it is our opinion that the uncertainty :sherent in the method is respon- go exception. About 8 per cent of the animals sible for the lower values in the 600and WOO ppm. &&d were omitted from consideration because concentrations and that no sigdicant effect od d %& infections. In view of the fact that a total h e r weight was found. d 180 animals, including 16 h t dld generation Using the findings of D d d s o n (4) on kidney nu,w;u used on the chronic vapor studies, there weight, all groups were n o d fortheir particular not an unduly high incidence of infection. body weight, in this respect. The kidney weights There were no deaths among uposed animals were proportional to those of the controls, which auld be attributed to the effect of butadiene. was to be upeaed as no kidney pathology m8s 'm~ i m &showed no sign of anorexia nor did apparent in any uninfected mt. && vigor or activity visibly diminish during the period they were expsed to the vapors es- BLOOD CYTOLOGY --_.cept insofar as they developed extraneous infec- NO blood dyscrasibs resulted from exposure to The rats rcaived their6rst exposurea t the butadiene in any species or at any concentration. of 68days. At this time the average weights T h e routine procedure included monthly hano- 3--* 4 groups were practidIy identical. At the globin determinations, aythrocyte, leucocyte, and -tion of the exposures the weights were 90.5, differential counts. I n addition, on dogs and rats u.3,and 81.2 per cent of the controls for the 600, the dotting time, reticulocyte count, and the mean a,and 6700 pprn. concentration groups, respec- corpus& volume were determined. There was +-. These data show that the apsures had a no progressive hacase or dwouc in any of the dcfmitc influence on the growth of rats,which was values. Shifts in the blood picture w e transient w y pmportional to the concentration of buta- and not indicativeof any deet fromexposure. diene. The bnal weights of the surviving male &ea pigs indicated the same txend. Too few F ~ a r a m* tabbits were wd to make comparisons on the T h e question as to whether ornot the fertility of hsis of growth, md rabbits are notoriously erxatic the rats was depressed because of exposure to buta- in this respect at best. The 4 female dogs fluctu- diene is debatable dcpendmg on the interpretation Ued in weight from week to week and, when given to the concept of fertility. If the criterion of d d ,they were heavier than at the start by fertility is d e n as the number of litters per female -*4.4, 11.1, 8.0, and 14.7 per cent, respectively, for conceived in a given time period, then it is evident m-4 600, 2300, and 6700 ppm con-- that the 6700 and 2300 ppm. groups were definitely :% affected by the exposarc Even when the banen %e finalratio of body length to b ~ d wy cight for females are disregarded this inference is true, for 2300, and 6700 pprn. ratswas 43,8.7, and the number of litters per f d e on this basis was Cmt IUS W tbt Of the mtrok. HOW. 3.3,2.72,25, and 2.62, respectively, for the 0,600, comparison With the ranges published for 2300, and 6700 ppm. groups. in0 rats Of the WU- (4) kdi- However, a recent workon the rat (3pointsout: ~ ~ g m u p s C a n b s"Fner~tili~b~ at its maximum when rats M from 1 0 0 - ~dafl of age. At this tima the avenge g liver and kidney weights the number of .young in a litter should be above the d by sectionof thecord and we= norm (six pcr litter)." This statement might be completely. This treatment hs interpreted M indicating that the cohccpt of f t r - ig#& er weights to avenge only &ut 60 tility includes litter-sizeas weU as litter frequency. cmtof thosercported by Do- fornormpi If such ir thecase, butadieneet 600ppm.inaas;d k-, ntr not exsanguinated (4). Howcva, corn- fertility because these femrln ~roduced8.4 PUPS ..... - , .. agcd 7.9 and 7.8 pups per litter, which is equivalent retinal ganglion cells, and the other retinal lay- m b b a t d h g to avoic to the control p u p and well above the so-called displayed no abnormality. Sections of the opcC &it from static dearic anormal litter size. nerve with adjacent retina stained with osmic p s e r e u s e d . Thewor The firrt S a l generation rats which were allowed showed no degeneration of myelin s h e a h . @a 25 p a cmt by vo to live and were with their parrnts were No pathology whatever was noted in the a d r e q I #J rngm-fittr)mixtruc 0: represented by only 2 females and 2 males in each heart, kidney, skeletal muscle, pancreas, s p l q +dud loss of lab* anantration group and therefore did not furnish testis or ovary of either the exposed animalsor & &h rapid rccwer~rof tb &dent data to calculate fertility. All groups controls. ~erposurcThipu, produced progeny, with the control and the 600 The livers of 68 per cent of the 6700ppm. group e d to be suitable for c ppm. group responsible for about 3 times as many revealed light cloudy swelling. As this conditiop &xi in the death of the as the 2300 and 6700ppm. p u p s . occurred in only 10 per cent of the control group, &aiwitllillZto35min The evidence obtained from guinea pigs and rab- it was probably a response to butadiene. HOW- +iIe the completion or bits further substantiates the argument that fer- ever, in all cases, with the exception of 2 rabbiu, mrk on the day of expost tility was not i m p i d by butadiene as all guinea pig groups were about equivalent in number of progeny. Guinea pigs produced 16,13,10, and 13 pups, respectively, for the control, 600,WOO, and the cloudy swelling was quite light and therefore of little signi6cance, for this phenomenon map occur as a physiological response to any sli&t stimulus. Congestion of the liver occurred s p F- 9-. TAB1 .--~DwozrsOR &RzxEs or WPH 25 I 6700 ppm. groups. In the case of the rabbits the radically among the 4 groups, but as it has no zL Is. 600 and 2300 ppm. groups had no littm, whereas particular &tionship to concentration it is r b the control and 6700 ppm. groups had 24 and 27 garded as of no significance. Fatty infiltration pups, rcspdvdy. The dogs were all females, occurred in the livers of 3 guinea pigs, 2 from tke but they were not bred during the exposureperiod. 2300ppm. and one from the 600ppm. group. 'This sa-. Embryos found at autopsy were considered as finding cannot b t explained, but it is not having been born, in all the above data. No evi- aently consistent to be noteworthy, and no o k dence of degeneration w a s~een in any of the tes- specis showed this effect. ti& sections examined histologically. It is Lung congestion oaurred quite uniformly in aR entirely possible tbat any apparent effect on fer- groupswith the exception of the 2300ppm. animals tility was c a d by the hereditary characteristics which had an incidence only one-half as great ar of the individd a n i d concerned, which arbi- the others. The fa& that the controls show a trarily limited feauadity. This would Seem to be higher perctntage of this involvement than any more logical in view of the evidence cited, than to other group discounts its being the result of eqo- attribute damage or alteration in function to the sure to butadiene. effect of butadiene inhalations. - - Nficfmc PROPERTIEOSF B G ~ A ~BG~x,zor, The average times ob: AXDTOLUOL FOR RABBITS &' e various rctlexes and Blood chemistry studies d e d no abnormal d u e for urea nitrogen, bilirubin,or glucose dur- Rabbits were anesthetized with butadiene in order to determine its effect on the body r k bits undergoing anestk 'r.o-lume of butadiene t inp and following the full mrx of 202 exposures duringthe inductionperiodand until death ensued, to butadieu& Routine Urinalyses for albumin, and thebutadiene content of the blood duringan& . sugar, and. ~ s t slikewise yielded no abnormal thak Thisoperation also compared the narcoth dUlS properties of butadiene with those of benzol and toluoL - Butadienewas meteredfrom thestorageq h d a t h u g h a calibrated flowmeter and diluted witl house air m e t e d through a second flowmeta. Thebutadiene and airweremixed in a4liter bot& and conducted to a 6-inch hollowrubber bail fittcd with inlet and outlet ports. A hole about 15 indm in diameter was cut in the ball to admit the rab bit's nose and mouth but not the eyes which to be remined for rtaer actionsp d u a d by aae th& The entire set-up was con;tructed of gtr-r ............. -.- -..':_-.-&,.L:-..-_ . .. ..:- -.. .. .. _.-. . . ?_ I - .. -.. ' - . .-; - . .- .. . . . 73 ier retinal layen $3.7-P& &ber tUKg to avoid explosion which might A mechanically driven sYr;nge was used to de- ons of the optic d t from static electrid discharges if metal liver benzol at a constant rate into a vaporizer. i with osmic a& ip.rtswere used. The work of others (1) indicated through which metered dilution air was supplied. 1 sheaths. .-*t a2S per cent by volume (2S0,OOO ppm. or The vaporair mixture was then led into a 4-liter xlin the adrenal mcreas, spleen, rmmgm./liter) mixture of butadiene with oxygen mixing chamber and thence to the rubber-ball in- loss of Labyrinth and motor reflexes, halator previouslyd c s c r i i . Trialsdemonstrated Aanimalsorthe $b rapid recovery of the rabbits after removal that a concentrationof 45,W ppm. (lM.0 rngm.1 :from exposure. T h i ~concentration in air was liter) was necessary to produce death in a 30- 6700 ppm. group ..folmd to be suitable for our purposes since it re- minute exposure, which is roughly i that of the b this condition in the death of the majority of rabbits ex- ie control group, ?@ed within 25 to 35 minutes and therefore made TABLE 2 utadicne. HOT- possible the completion of all necessary analytical SYXPTOXS OR OF 10 RABBITSUSDERGONO Lion of 2 rabbits, mrk on the day of exposure. mw 35 TO 4.5 PER CLvr BEXZOL ,ht and therefom henomenon may ;e to any slight er occ~rredspoJut as it has no ltration it is re- EA* r r b TABLE 1 VAHlB m -4m s m u r s ox REFLEXESOF 29 RABBITS USDERCONC ---.-. ANESIKESL~ w m t 25 Pzn CENT B WArn ~ I E N E mli 0. lINx ..............I Light anesthesia, rrbrcd. AYLUCL zlvr or -VU 1-( 3.7 .. 'atty infiltration . pigs, 2 from the Excitation, runningmovements, trrmor~, ...........................chewing ....L o s s o f p u p ~ r e f l a t o s t r o n g l i g h t 5.0 6.5 3m.group. This .............t it is not SUE- TLightanesthcdr,rriaxcd,. 3 .............hy, and no 0th~ ,bof pupilkrprcacX t O . ~ b nlgight.. a t i o n ~b tkpupil. *:.3 uniformly in all ............................300 ppm. animals :-half as great M controls show a 'bation, movemc~bt,remors, cheaing h o t blink&totactrtd stimulus.. ................Dry des, laryngcd, tracheal or bronchial .b h m t a r y ilbkiug.. .ement than ang kteandmxkddilrrtionof thepupil... .............................. ,he result of expo Death. 1.6 3.8 3.9 4.6 6.5 7.1 1.4 11.4 23.0 LPIDnOuevpaSoitSllohluaf.nr.btp.at.ir.cn.yak.bn.r.ltie.rn.falk.ec.ix.tni.ogt.o.n.....t.a.....c...t..n....a........s...t..i.m....u...lr..u........ ii.4 12.0 15.6 36.2 .TABLE 3 SXXPTOMORSREnaes 01 6 R A B B U~ NDE~CO~SO ANesTgEsn TRW 4 S TO I R x CENT TOLUOL V m n IX &In DIENE,BENZOL The averagetimes observed for the occurrenceof -sMIowo.IL.px - - *-DE -Or OCCCXULVU 1-( -BITS i t h butadiene i~ the body d a e ntildeath ensued blood duringanc --3aredthenarCotj ne of benzol ;UI . ie storage cyrindc and diluted ~t m n d hwmcte i in akIiterbott * rubber ballfit& ,leabout 14 inch toadmittherd c eyes which we produced by ,n;tructed of gfa Dath............................... 40.0 ___ecp anesthesiawith20-25 per ant tion, and artainl and irenous blood slrmpla were .A-. gained 702 gm, during the 34 a e n t was calculated for bcntol. The benzol con= .__which butadiene was srlminip..- tent of thcblood was dctaminai by a m o d S a t i w 3vct3ge value in tcrms Oi m-.,':nl. of benzol in Thcrc is no intention on i)urpart :o scygcst L L ~ . the arterial blood from the femoralartery after 15 diene for consideration as a safe m a t e d for g a minutes of inhalation was 0.1843. for venous blood erai anesthesia, as there is not complete mumlar from the femoml vein 0.1607, while at 22.5 minutcs relaxation even in the fourth stage. Furthermore, &e cuacentra$on in the abdominal aorta was death ensues rapidly and abruptly when the m h 0.2754 and in the postcava vein 0.1558. Death is kept in deep anesthesia ior any length of time ensued on the average in36 &Utes with the range No conmntration other than 20-25 per cent by covering22.5 minutes to 71minutes. This finding volume was used for thisphase of the work anti a indicates the wide difference in the tolerance that complete and thorough study of its narcotic ac individual rabbits have for benzol M ~ C O S ~ . Re- tivity \vas thought unessential. However, judging flex actions and symptom were variable in time of fromthe rapidity with which rabbits recover from occurrcna The results appear in Table 2. deep narcosis, it seems reasonable to suppose that, The same apparatus used for producing benzoi- if humans can be removed from accidental em' air mixtures mu employed for toluol. .i concen- sure to anesthetic concentrations while theii tration of about 55,OOO ppm. (24991 mgm./liter) respiration and heart actior: are still strong, they was found to be letha for rabbits in about 40 wili quiddy return to normalcy without ill effects minutes over a range of 2 1 to 62 minutes. Wide differencesin response were xzoted. Blood samples D I S T ~ X B ~COo ~Xm c m i i sOF B I S T A D ~ Z were analyzed for toluol by a mdication of the microcolorimetric method of Yant and cc-workers (7). Thearterial blood conmtration in mgm./mL of blood averaged 0.093 a t 13 minutes and 0.104 at 33 minutes. Venous concentrations were 0.054 at 14.6 minutes and 0.086 at 30 minutes. The time of o~currmaof symptoms shown in Table 3. The dstribution coe5cient of butadiene beheen water and air was found to be 0.25 by equilibrating a known volume of water with pure butadiene vapor in a bath at 37.5" C. and detuminig by analysis the butadiene content of &e water using the iodinepentoxidenethod. This figurewas conh e d by bubbling pure butadienefor 2 to 3 houn DAILY Ah-nox through a series of 4 tubes i m m c r d in a water bath at 37.5OC. Five ml. samples of water were Further evidenceof the lack of permanent injury then withdrawn and analyzed with results com- from butadiene may be g b n e d from the esperi- pletely in accord with those of the h t method _L ... ments on daiIy inductha into fourth stage anes- The distribution c d i a e n t between blood and thesia Two rabbits received 15 consecutivedaily air, i n d r a y was estimated stniiarly. Five mL inductions in a flowing vapor-ak stream and one samples of oxalated rabbit blood obtained by car- _ra.bbit 34,with 200,ooO to 250,000 ppm. of buta- diac puncture were equilibrated by mechanical diene. It required less than 2 minutes for loss of shaking with pure butadiene during a-20-minute motor and labyrinth d e x e s to occur at this high interval at 37.5OC. in order to saturate it at atmos- cancentration, but the administration of butadiene pheric pressure. At the end of this period thc was continued until wide dilation of the pupil was excess butadiene was expelled from the equiliira. seen and stentorian breathing and d e s were heard tion vcssei by displacement with mercury. Thc with a stethoscope. These last symptoms oc- tube, then containing only blood saturated Wit1 a d within 8 ' to 10 minuts. Rewvery of --- balanceand muscular control was achieved within 2 minutes after removal from butadiene. No . pathologyd d be detected in any of theserabbits. .- .+_L-*-W e w t gains were not adversely affected and the ----:-.-,-*bits rnaintahd th& d e n t condition. .- .- other rabbits d v e d 21 M y a n e s t h e b -_- - .-.:=-- .dons followed by a 1Sday observation period. - These gained m&htnormally and had no cam- . - ---. plications. On the basis of the findings on these 6 *bits thedore it u apparent that p t t d 811- butadiene, was placed in the iodine pentoridc analysis train when washed dry air was dram through it at 0.2 liter/minute for one-half hou while it was mechanically shaken. An additiona half hour of aeration with continued shaking re d e d no more butadiene in the blood. T h e rc sults of 5 analyses yielded an averagc distsibutior &dent of 0.603 (range O.SS5-O.662) betoxnlated rabbit blood and air at 37.5"C. am 760 mm. pressure. The average in wiw distriiution &dent bc thuia withbutadiene had neither deleterious effect tween blood and air in the rabbit. corrected for tb be day on :vhich the ex;-- ?i.?Z.iWSg.arfoe ubndbtaosebde 0.654 (range on 19 arteri w e d from 10 individual r i &S'd25 per cent butadiene in were from the femora +bdominal aorta, and 3 from &&dore death. The average .$&.which the femoral arter Z.mscas~albaorustam1p0lemsinwueteres, whi take s h u t 17 minutes. Death u 23..-I.- minutes. Attempts me: from the femorals first and -.toneum was opened and th Y.. S-.tad, or, if the latter collar was punctured after 0per.i: Fair agreement prevaa .-isoik4 blood distribution cr lends support to the hypoth, -7jmtadiene from inspired ai G3roass of simple -on 3Ivcoli of the lungs. VfaE P S Y C R O - ~Resp "&' B~AD~SE,TOLUO -$-3!r.In an attempt to evak psycho-motor response of h concentrations of butadien tapping rate and steadines before and during exposure Pulse rate and blood pressu subjective symptoms we hippuric a d d excretion toluol and styrene exposure separately. ..+ The influence on tappin, Ismeans of a long papet k p -?-!@L ting pens. One pen rf Contact was made dosaithecircuita .. c .. ... to suggest butt b y on which the experiment was urricd out, eentrations, the tests were made more strenuous naterial for ga- nplete musculu - Furthenno? when the a n i a . length of found to be 0.654 (range 0.535 to 0.801). This is based on 19 arterial blood samples col- $2;wed from 10 individual rabbits during inhalation 25 p r cent butadiene in air. Ten of the sam- +were from the f e m o d artery, 6 from the by cutting the original 4.5 I 6 in. sheet into 2 parts and separating them a distance oi about 12.5 .' inches. A similar strip or barrier HXS placed between them to prevent sliding the stylus from one plate to the other. A metal stylus in a woodm -25 per ctnt by &,&mind aorta, and 3 from the left ventride just handle was used to make contact instead of the the work and a "'i't,&re death. The average time under anesthesia metal h g e r stall. Then, too, the kymograph its narcotic ac. *a which the femod artery samples were taken speed wvm reduced so that a complete circuit of the :owever, judging its recover from to suppose that. 2--5- about 10 minutes, while the aortic and ven- paper was accomplishedin 3 minutes instead of the samples were taken on the average at previous one minute, thus increaiing the fatigue z. P- a t17 minutes. Death usually ensued in about factor. By effecting these changes it xu antici- accidental ZJ minutes. Attempts were made to get blood pated that any distqxbance of the psychomotor ns while thek .till strong, they ithout ill effects. from the fernorals h t and if that failed the peri- response by the vapor inhalations would be more --%'toncum was opened and the abdominal aorta en- readily detected. &, or, if the latter collapsed, the left ventride In evaluating the results of the tapping test, the m punctured after opening the pleural cavity. number of taps in each &second i n t e n d oi the P BLTADIEYE ---.Fair agreement pnvails between i n Oivu and 3-minute test period were enumerated. The lom- .tadiene between by equilibrating pure butadiene determining by the water using s figure was amfor 2 to 3 houn ned in a water s of water were - k d r u blood distribution &dents and this fact -Jmds support to the hypothesis that the passage of *-'-butadiene from inspiied air into the blood is a of simple diffusion of the gas from the --thrcoli of the lungs. -e-1 P s U ~ O - ~REESPONSE OF H m S TO .-. BUTADIENE,TOLUOL,AND S"E +?h an attempt to eval~atethe d e c t on the est, highest, and mean scores for these &second intervalswere recorded, and the coefficientof varia- - eltion was calculated according to the following formulae: Standard deviation and - ~tandarddeviation Coefficientof variation mean 1 th results com- psycho-motor response of humans inhaling various where d is the deviiation of the number of taps in l e drst method. xeen blood and concentrations of htttadiene, toluol, and styrene, each &second interval from the mean, and n is the tapping rate and steadiness tests were performed total number of 6-second intervals in the test arly. give ml before and during exposures of two male subjects. period. The coetiident of variation expresses Ibtained by QIby m a a n i d Pulse rate and blood pressure were determined and numerically the magnitude of the fluctuation in subjective symptoms mere reported. Urinary tapping-rate and is therefore an indication of h g a 20-minute hippuric acid cxaeti~nw a ~followed after the e m t i c performance. rate it at atma- toluol and styrene erposurs;this topic is discussed The steadinesstest was perfomed by the subject this period the j;itpaately. holding at arm's length for a period of S minutes x i the equiliim The influcna on tapping rate was observed by a *-inch wire in a +-inchhole drilled in a strip of mercury. Tbe f a long paper kymograph fitted with 2 ink copper. The contacts of the wire with the periph- saturated with pens. One pen recorded the taps and a uy of the hole were recorded on the same kymw dine pentoxide pcn marked off each 6-second interval b graph used for the tapping studies. The per- airwasdam on from the strai centage of time the wire was actually in contact t onohalf h e with the sideof the hole was determined by measur- An additiod -.ing the width of achdeviationmark on the record. ued shaking r i srranged so that contact wa5 Steadiness and speed of reaction are better -ti- blood. T h e ? he&, 4 5 x 6 in., with a wooden mated by thin method than by the simple summa- age distributid k,pkced in the center'of the tion of the total number of actuai contacts. 0.662) be- w85 made with a metal finger stall . The initial stesdiaeu tcst adl day was made -lt - 3<7..5.O_C._. - and "*, I &dent dosed the circuit and d&cted the writing prior to establishing the gas concentration because .in 2000 and 4OOO ppm. buta- of the initial eye irritation a d b p some of the toluol were done with thii materials. All the human uposures were ,per- mmcted for thc gedleDt Obtaining no signXcant deviations formed in a 4ooo cu.ft. room,in which fans were .tCmpMturedI . 1. ... -. tapping , *rat.e-w.hile inhaling these am--. arranged to produce rapid and thorough mixing of . _.. .I -..._-........ . . 76 the air. Butadiene \ V ~ S bled directly from a 8 W pprn. butdime: i1O subjccdve jyrpptoms :e. cylinder, toluol was automatically metered into a ported, probably because of preormption with .. heated dish to evapontc the h i d , and styrene was the control of the conccntration. evaporated at room temperature from large wicks 200 ppm. toluol: transitory mild throat and eye in an air s m m . Vapor concentrations were fol- imtation; slight eshilaration. lowed with the interfcrometer and controlled 400 ppm. toluol: mild eye imtation, e a t i o n -' manually. when performing the steadiness test, lassitude, BIood pressure was taken by a d t a t i o n , using quickly passing nausea, and hilarity. a sphygmomanometerafter the subject had rested 600 ppm. toluol: lassitude, hilarity, verbosity, 5 minuts or more. These r e a d i i iu well as boisterousness; after termination of expcsure, pulse rates mere too variable to be of any si@- anorexia and listlessness. 8OO ppm. toluol: metallic task, transitory head- TABLE 4 ache, estmme lassitude, scotomata, verbosity, b ~ n z v u ~PmROIYXOLor O~SERVATIOXSD o a r r ~ ~ inebriation, slight nausea. HUMANEwosrmp. IO V m a s 800 ppm. styrene: immediiatc:eye and thmat irrita- tion, increased nasal mucus secretion, pto- nounced and persistent metallic taste, htless- ness, dro~iness,impairment of balane; aim termination of exposure, slight muscular weak- ness and unsteariines, accompanied by inertia and depression. It should be emphasized that, after the subjects had endured a single uposure to butadiene or ~'~14U~8Woppoooxppopoop)pppppmmpppppmmmmmm..bh......tbtutstotoo&tultalyluuutSrdooaeoodlnlldi.l...tibe......m....en.........c.e.............................................. toluol, they became rnuch less aware of subjective (11 symptoms on repeating the exposwe at the same 266 or a higher concentratioa Other worken (8) 136 have found a pronound improvunent in tapp;nP 138 rates near the end of the day and exceptional per- 176 forrnanasduring evening trials. This factor tends -155 717 630 to offset the effect produd on the subject by the inhalatian of vapors which would be expected to have their greatest and most marked &ect at the -*tested at these ament; ' w i n e s was apparent in * ~ p ms.tyreneand 8 0 ppm. r 'ppm. butadiene showed thk pt,but results at 8ooo rppmzimately nonnaL The butadieneand toluol show @iicatedby the s t e a d h a s t 'On the M of symptor rjaunan subjects concur in styrene was most ob: '600,400,and 200 ppm, toL order, and that 8OOO ppm. L 90 greater than 200 ppm. t h ppm. concentrations 01 tionable only from the point 5 soon forgotten. The fac +&ation of butadienewas f lccords on steadinmi tests @ts were probably physic? ptonthedayofthe4OOoF paformed poorly. The lo toluol likewisedid not i d u +tion to the amccnfxati #.'Lhis observationleads to tl thrrshold conenhation be dthe steadinessand tappin widely. This threshold c steadiness test was reached at 800 ppm. and was not ermat8Oooppm. hth antration apparently w a aposure to any of the mate The subject of psychomc - ~ r desserves further stu "qthe action 00 humans 4 + y u i o n s of VaPoE). --- METJlEoLXc neutheawcfns . M.3 SI re- . with 4ep iation itude, nosity, asure, head~osity, irritaPr* jtless after we&nertia bjects :ne 01 ectivc . same IS (81 ippinr -11tepnedrl 3y thl ted ti at th durb Jy, bc s t y4 a t tk t the ltttin 3ditiC of ax n fro d e tl jt p1 cult! me 1 i efft ,ist =tic 3PPi tor :ma tested a t these concentrations. Marked un- toin, biacetyl and- \ e IC. /.- . . .'., -conceivably was apparent in both subjects in 800 might be metabolitesformed from butadiene. No bppm.styreneand 800ppm. toluol. Four thousand appreciable differences were found between the ppm. butadiene showed this same effect to a less animals elposed to butadiene and the unexposed ;mt,but results at SO00 ppm. butadiene were controls. Because of these negative results similar irpproximately normal. The lower concentrations studies following human exposures were omitted. d butadiene and toluol showed little or no effect as The hippuric acid excretion of humans exposed +dated by the steadmess test. to toluol has been shown to rise considerably-dur- ,?on the basis of symptoms produced, the two ing the 24hour period in which the exposure is 3man subjects concur in the opinion that 800 made (13). Similarresults followingoral admink- mm. styrene was most objectionable, that 800, tration of styrene to rabbits have been reported m, 400, and 200 ppm. toluol came next in that (14). Twenty-four-hour urine samples were col- &is,and that SO00 ppm. butadiene had an effect lected from both human subjects during toluol and po greater than 200 ppm. toluol. The 2000 and st?-rene esposure. Hippuric acid cscretion in- pprn. concentrations of butadiene are objec- creased with the severity of the exposure to toluoL -.el only from the point of vim of odor, which The greatest exuetion was 7 gm.124 hours above .k soon forgotten. The fact that where the con- the subject's normal as a result of 8 hours exposure "&itration of butadiene was SO00 ppm. much better to 800 ppm. Likewise, although the data are -+*&, =.qhdues on steadiness tests were achieved inhaling 4OOO ppm. indicates that both than sub- meager, styrene taused a considerable rise in hip puric add excretion. Four hours exposure to 800 were probably physically or mentally below pprn. caused an added excretion of 32 gm.in one p r o n the day of the 4OOO ppm. tat and therefore subject. qaformed poorly. The lower concentrations of Previous work on monomeric styrene (14) has rtolwllikewise did not in5ucnce steadiness in pro- revealed that neutral sulfur increases in rabbits *on to the concentration, in either subject. whish have received styrene by mouth or by in- This obsemtion leads to the belief that there is a halation. Therefore, since the opportunity pre- threshold concentration below which the results sented itself to make such determinations upon of the steadinessand tapping tests willtend to vary humans inhalinga known concentration of styrene, widely. This threshold concentration for the suliur partitions were performed on the 24-hour sk@ness test was reached for styrme and toluol urine samples collected during and after the expo- at 800 ppm. and was not attained for butadiene sure. Neutral sulfcr for one subjed increased b =en at 8OOO ppm. I n the tapping test this con- per cent above hi normal level, but the increase -_centration apparently was not reached during ;+to any of the matuiaIstested. .&Tk subject of psychomotor effects from solvent '-*n deserver furtherstudy as a m u m for judg- ;&g the action on humans of exponue to low con- for the other was only 17 per cent. These results are not conclusive, but it was considered unwise to subject humans to further exposures in order to prove thii minor point. -- SY- AM) CONCLUSIONS . hfEUBOLIChODDcls possible metabolic prodacts of butae in the urine of rabbits which were e and hithe urine of of the &month re- significant amounts of 1,2-glycols, c aldehyde, pyruvic aldehyde, act- 1. Butadiene in concentrationsof 60,2300,and 6700 ppm. caused no signidcant progrrsSive injury to small animals during an &month uposure period, 6 days a week, 'It houn per day, although the highest conuntration retarded growth slightly and caused light doudy swelling in some Liven. Data on fertility, blood cytology,body weight and length, organ weights,blood chemistry, urinalyses, and miaopathology are dixussedin support of thii statement. 2. The iodine pentoxide method of analysis has beta adapted to the d e t c h t i o n of butadiene in air and in blood. 3. The distribution coefficient for butadiene b e -. - - 78 J O W G OF INDUSTRTAL HYGIENE AND TO?cICOLOCY G./j-&.? ;c +I. T!ik subatantid aqrccment ol)jcctic,naLlc vapor the!: ~ ~ c - 1S.PA, (~004.1%. aindimtc:j. ~ i l at i~c p ~ a g ( o: i butadicirr irom in- 100 ppm. toiuol arc next in that order, and spired air into thc blood is a p w of simplc dif- fusion of the gas irom the dvcoli and simple solution in blood. 4. Ansthetiration experiments on rabbits were ppm. butadiene had an effcct no p t c r than zh, ppm. oi toluol. On thc basis of psycho-mot,, eflect, which m a y indicate a tendency to card- ness and accidents, 8OOO ppm. butadiene is ~rg CaZTied out to compare the symptoms, rdexes, worse than 200 ppm. toluoL and blood levels of butadiene, b u w l , and toluol. The -tic action of butadiene was less thanthat of the other two. - 5. Investigation of the urine of rabbits after chronic and acute expos~mfailed to reveal the presence of any metabolic products of butadiene. 7. Butadiene is p r a c t i d y innocuousaside from its narcotic d e c t at very high concentrations a has little if any cumulative action. Provided & lower explosive limit is not exceeded, it is that the health of anyone inhaling its vap?rs will imp&, many may h d i& & fumes. The acute rear at length in the put, e~ fev+o, and will not he idmion here. It is 1 The increase in urinary hippuric add excretion in objectionable. Humans accidentally anesthet5aj humans following exposure to toluol was verified, by extremely high concentrations should rem and suggestive information obtained along the quickly to normal if they are rescued while rcsph same line following styrene inhalation was noted. tion and heart action are still strong. Deep 6. Two human subjects expobed for 4 to 8-hour thesia, however, is likely to terminate fatally ina periods agree that 800 ppm. styrene is the most short time. &rou;, of \v&hs sho\ring thc dl be rmllrrl from our origin2 BIBLIOGRAPHY the lung changes as seen on &z collsistcd of disaete nodular c (1) VONOETIIXGEN, W. F.: T e b ' and potential tionoftoluene -+of Interior,U.S. Buratld &gas of aliphaticand~ l ~ r m th-i t Mines, Reportof TnMtigatiom3323, Dec 1936 public Health Bulletin No. W , Washington, -D.C 1940. (8) Warpp~eG, . M.: Manual of mental and physbl The Mers of thcse mu V~53~Ed,W~~~YO~Lrq (2) The stonge of 1:3 butadimc Rcsearrh Bulletin mtimore,1919. -NO. 7.381-B. Storpge Fellowship, (9) DEEw,F.: Quantitati~emethods for the deter- c d u b and the hirum .. -- =on h t i t u k , P i t ~ Pda. -h f,, f& in 4 (3) HAGcApD, E W.: An aenrrrte method of deter- Jour. Lab. and Qia Med, 10: 59, 1924. mining small amounts of ethyl ether in air, (10) DAIKNE, D.: Oxidation?in the animaI0- blood, and 0th- fluids, together with a deter- Jour. BioL Qltm,3: 57, 1907. *tion of the e t of distribution of between air andblood at various tempera- tru& J. BioL chun.55: 131-143,1923. (4) DONAIDSOEN,E:Therat. Data andreference tabla 2nd andRevisedEd., Wstar Institute, Philadelphia, 1924. Q G p m w , J. Q., AND FILppzs, E. J.: The rat in b r a b y invcstigatim. J. B. Lippincott, (11) Wcial and tentative methods of d y s k of *%e AOAC 4th Ed., p. 171, George Bmtj Pub. co., M m WE, 1935. (12) -xx, A. J. AND Nmwm, R W.: P r o e c glycol: rate of metabolism, absorption, excretion, with amethod for atimptionin bodg Buidr J. Phorm. dt Erp T h C r . 9 60: 312-a -^-- were rrsponsiblefor tt OR the S-my films. ulted from the use c on very confined Lobs iz of 'gasoline and milk tank. Philsdelphis, 1942. &(Q Stmm% H. H,YANZ,W. P, S. J., P m ,F. A. AWD slmns,R R:Absorption, - ,*tion andr?limirut;mofbmceneby body -_ .- . '.- 'tisue3 md fluids of &g apolcd to knrcne t ~ o ~Tabrs J.. 23: 2044,1941.