Document a4GxOmpGqeKjY41GzB13E0M5b

Acute Inhalation Toxicity of Vinyl Chloride to Laboratory Animals E. MASTROMATTEO, M.D., A. M. FISHER, Pli.D., H. CHRISTIE, B.Sc., and II. DANZICER, M.D. Division of Industrial Hygiene, Ontario Department of Health, Toronto, Ontario; Department of Physiological Hygiene, School of Hygiene, University of Toronto, Toronto, Ontario; and ll'ci/and County General Hospital, Welland, Ontario Introduction w-rilx.'d as very slight. Elimination from the I FIRST prepared in 1633, vinyl chloride has come into increased use in the Inn drc<*idc in was very- rapid. Tltesc nutlton quoted the of Schaumann* with experimental animals, nits and dogs were nldc to endure reposted ai the production of polyvinyl chloride resins. Tliecosis without any pathological evidence of fin; and explosion liaxard of tlie monomer And its narcotic properties on acute rxj>o*urc arc well or kidney damage. According to Schat concentrations of seven to ten per cent in? known. A* an industrial material, however, it has would lie nnrcotic to humans in a short time7'^* been regarded aa of moderate toxicity. A Thresh 12 per cent would be dangerous. old Limit Value of 600 ppm was established by Vinyl chloride has been studied u a the American Conference of Governmental In anesthetic agent. Osier and associates* noted1 dustrial Hygienists. incoorriinated muscular activity of the Xo industrial fatalities associated with its use ties and cardiac urrythniiaA of a serious have previously been reported. It was therefore of special interest when two fatalities occurred in were olwcrved in all six dogs used in their expend inent. Carr and others7 found that vinyl chiorida a plant handling vinyl chloride. This plant is en produced sensitization of tlie myocardium- gaged in the polymerization of the gaseous mono three of sewn dugs in which it was adminiitaedj mer with the aid of catalyst*. One worker died as an anesthetic agent. while cleaning nut a polymerization \*o*sel and the Two eases of vinyl chloride gassing occurred hi other while working in a pit. J>tails of these two a factory in Great Britain wl*ere ixdyvinyl chlor-l fatalities have Urn rejwirtcd by one of the au idu resin was U-ing made. These were reported byaj thor!*.* the Chief inspector of Factories.* In one esse Published information on tin* acute toxicity of pnxvss worker was standing outside a polymer*^ vinyl chloride to experimental animals proved zation vessel and washing it with a water stream.. scanty. Patty, Yant and Waite* in 11*30 yvjmrtcd After ten minutes of this he* suddenly collapsed! on tlie acute response of guinea pigs to vinyl acros* the 0|)0u manhole. Artificial resuscitetaop] chloride. They found tliat cxjiosurc to 20 to 40 was successfully applied. Suljacqucnt symi per rent in air killed guinea (rig* in short time; cN|H*ricnccd hv litis worker wen: tightness of ths^ ex|ure to ten jier cent was emlim-d for several chest, nausea, alsfoiniiial |iain and huadaclw. Tb* hmin*. Congestion ami iilema of the lung:- with M tnhd (Ha-uiTcd in a maintenance worker )>yi*en'iia of the liver and kidney* were u<,t-!. who wa. overcome while repairing a vinyl cbioridOj P*opW and Leake* found tin* minimal anes leak. Both men were hospitalized. Another worion thetic range of vinyl ehlnridc in miec for whose hands wen* neeidontally sprayed witho ten minutvs was 8 to 12 i>cr rent in air; 25 to 30 vinyl chloride liquid under pressure developed *| |*T wnt wax fatal in ten minut'-s. Dogs :md rab bum. This latter case was rejKirted by Hst bits went anesthetized within <mc minute when cxjxixetJ to a concentration of almut IS i>er cent in air. Recovery was very rapid with no apparent .Such burns may occur with other highly vols materials when sprayed onto the hands as s lit; untoward effect even after prolonged anesthi-sia. under ptx**sure. Lehmann and Hun-4 noted that vinyl chloride Filatova and (irrmslxTg1* in 1957 reported was highly nan-otic hut had a wide margin !- hygienic conditions in a polyvinyl pr tween its narcotic and letluil couccntrutiim*. Its plant in tin* U.S.S.R. The plant was engaged in? local irritating effivt and its toxicity wen: de the iHjlymerizatiou of vinyl chloride by means wj 394 A catalyst. A vti1rati<m of from nlmut 2* Tlir-eshold IJ A sjirn rils'd iu v Itcc.iiise o aIhivc it wua (ion studies i chilly nvailab! fur cumixiris* information a rai change* in animal. Experknontel \ 'inyl Cldoi ia metal ey! grade with th tmriijr Wairr tontml BniliAS lun *C Mylrucni clilorii AivivU-n* Arrcl.IrhyAe lp*T rttl) (p*r r Bun* vinyl lem|M*raturv; 3 sweetish nduad its explo real. It has t5 . I nintalx: ^ in the study. itt the son - lard emu a;>. All wer* /-.'/ni/mimf. was 5G.0 litc: window and ; isil in g:e \ alvo 1 >i 1 tin* llirough coni limted Fisliei liv motor at n * meter. Tin iv coinbin* via *5 Y-tuU* mg to tin* n iKiitiimiug s' al-ulatiolis line the foil blonde in ai lit. All eon. oft as per x BFG03836 T Ihloride mto, Ontario, oj Toronto, tl, liimtioo from the hois quoted the mental animals. Mi endure repeated peal evidence of lit xiing to Schat > ten per cent in ns in a short time, rout. studied as a associates* noted tivity of the s of a serious nat .s used in their cx{ rid that vinyl ehlor ( tlie myocardium' h it was administ rlc gassing occurred; vliere polyvinyl chit hese aero reported' tones.* In one case g outside a ]X)lvmc -with a water ic suddenly colla; Vrtificial resuscitatk uheequent sympt were tightness of in ami Itcadnclic. maintenance work* airing a vinyl chlorh Used. Another wori ntullv sprayed wit pressure developed reported by Harris.^ otlicr highly volatil tlie hands as a liqi in 1057 reported or jmlyvinvl proceasinj )lant was engaged chloride bv means ot Industrial Hygiene Journal 393 s rtiUlyst. Air sampling was done mid tiic eon* etiitmtion of vinyl chloride was found to vary fn'in about 20 ppm to about 315 ppm. (U.S.S.R. Tlm-abold Uniit Value: 1 mg/litcr or about 400 |)|.ui}. A s|nstie type blood vessel disorder was d,bribed in workers from tliis plunt. bemuse of the recent fatalities mentioned Above it was decided to undertake acute inhalelion studies in laboratory animats with commer cially available vinyl chloride. Tliis was done both for comparison with earlier work and to provide information on tlic acute response and pathologi cal changes in more than one species of laboratory animal. Experimental Materials end Procedures Vinyl Chloride: The vinyl chloride was supplied in a metal cylinder under pressure. A commercial grade with the following specifications was used: Sprtifa ififio M tt*C ViW MWM MliMiue'C BrStwna >SlaHS muH Awtytoss vmildafcyS* Inn I'ufiiy (par mm) InapvriUM Cs*rM) t.NM.M Koss -ll to No** M I>Ps *! r--ihllr Vts T-tt N4 --xim-- IJ uSna Pure vinyl chloride is a colorless gas at room temperature; its boiling point is -13.9*C. It has a sweetish odor. Its flash point is given at --78*C and its explosive limits in air from 4 to 22 per <vtit. It Iras the molecular formula CH:CHCL . 1 fu'Hidc Mice, rata and guinea pigs were used in t lie study. Tost and control animals were taken :>>in the same laboratory stork. All were fed a >(:m<lard commercial diet and housed in the same way. All were of the same stage of development. Equipment: The inhalation chamber capacity was 50.4 liters. It was equipped with a viewing window and an inlet tube. Vinyl chloride was re leased in gnsemis form through mi adjustable valve on tlie top of the ronteining cylinder, then through connecting rubber tubing and a recali brated Fisher flow-meter. Fresh sir was pumped by motor at an adjustable controlled rate through :i" meter. The streams of air and vinyl chloride ucr combined at appropriate rates of flow by a ghira Y-tube leading through further rubber tub ing to tlie animal chamber inlet, to deliver a continuing stream in tlie desired proportions. Calculations and adjustments were made to pro duce the following flow concentrations of vinyl chloride in sir for delivery: 10, 20, 30 and 40 per cent. All concentrations are expressed in this re port as per cent by volume in sir. No determine* tione of vinyl chloride concentrations were done in the tost dmmlicr during tlie experiments. Experimental Proceduree: Different groups of five mice, five rats and fivo guinea pigs were placed in tlie chamber and exposed for thirty minutes to concentrations of 10, 20 and 30 per cent vinyl chloride in air. Similar grou|M of con trol animals were maintained but not exposed to vinyl chloride. At the end of thirty minutes ex posure the test animals wen immediately re moved to fresh sir. An additional group of five guinea pigs was exposed to a concentration of 40 per cent vinyl chloride in air. In all 05 experimen tal animals were involved. Observations were re corded on the animals during and after exposure. The sirimala which died either during the ex posure or after a delay period were autopsied soon after death. Two weeks after the exposure sur viving test animals and controls were sacrificed by blow to the head with the exception of four control rats which were killed by cT--nguination. All animals were examined for gross pathologi cal changes. Tissues were removed from all ani mals for microscopic tiTM. The lungs, liver, kidney and heart were removed in all cases. The brain, adrenal, spleen, trachea, lymph nodes, and the eye were removed from represen tative animals in each group for study. Tbs dames were preserved La formalin and sections made for staining with hematoxylin-cosin. Sjiecial stains were made wherc indicated. Observations Control A trimal*: No symptoms wen.- cxliibitcd by the 15 control animals and no deaths occurred. Ten Per Cent Vinyl Chloride: The response of animals exposed to this concentration is recorded below in summary form: Eip**M Tint Stutht illitatiM is itK*Md ista. tiiOTMid atocnr ISm is micr, lints mis tad guia-- pin. Incifsr'l s*w sativiur is sU *pwir*; tviuMii S --t--iliw is niss Pmiiiiwd tfwnsr. mwsdy pit *sd mu--uisr i--*di--li-- is ill ipwfas Mi-- asS rsis is aid* pmitios; mu--ulir is--ardisaiiss. trim--* tad twtuhioc ot utitniuw is |\a-- piss Kiw ssd ista sp--spdoua, fids-- plt --rr q--l--rfr bst * Masdlas. Mi-- sad law is d--p fvis-- pigis**dt--iH--wtthiw>pq as* Ex|xwurc was stopped andthe animals removed to fresh sir. All recovered within five minutes. Twenty Per Cent Tiny! Chloride: The response 20546002 BFG03837 T S9f; October, of animal* vx|A*eil to tin** concentration is re corded Iwlow in summary form: Ellawirr Time iminato' RfliaMx t nnnndinl* irriuuioa in ihiok ami ra Miarahr innavdtiwuna ia mifr ami rata. Mianand niton ihtir atriaa will) marked tremora and iwiirbint of the nimni' tim: wMteadiaraa tad munrulnr i(iMerdiaatiea ia fiuaea ihm. Mire and rata unaonaniMta with r|d inecular braatiiiMS tuinm |>tc u- aonaciMa bat ilnrii tnnrfcml iitrii iM. All animalain deet> naraoaia; reapiratam* Imaabr and ra|d. rWft nnnii; kniilkiM efc* and alntl- lav. BraathtM nurd in ana frothiaa at ntnnth and anauili in mien and rata. AU aaiiala ia deep aaiaaaia. Exposure was stopped and the animal* rcmovixl to fresh air. Mice ami rat* recovered faster than the guinea pigs and appeared normal within five minutcc except for otic mpuso wlik-li was dead. The guinea pigs continued to show iniist-ukir in coordination, unstcadim*# on tlair feet until 2d minute* after removal from exjwsure. Thirty Per Cent Vinyl Chloride: The nw|M>n*o of animab exposed to thin eoneeutmtioii is reenrdi*d below in summary form: Eapnari That tminaterl >ttpnn -- Uinpalmw*>l IrriuihHi iiiiMmliairl.v and tlae naia Iwenl irriuoun fi*ii'Vly thereafter. 1 Muae'iUr iaruardinaueu in mice and rat*. 2 Mice and rate in ask- iih marked trenmw ami teritehiM *f the estrenutiee,' munrvinr ineoorJiaauna iamdaaa im with devetopina Oaralyai of Ote eatremitiee. 3 All aaiiwab anemMeinua; >|>id irrelar reafarauMie in rnirer and ni* '>0> frmhina alanrl * and iwvitli; twiteliina "( etlmiiitm Mill >eeiifn-l aeanaoaaUy in cuima |xi> IQ Raapirniinneatnmnal in miee: lemifcinc alow and ahallmr ia rte: inea Ha* Mill nkihited weaaiunal lirilHiina atoremeata M the e<trrmi>ee 13 Kreathinc Mni'l*-*! ia rata: r*pmiinn aba and eiwlinw in aiiinea in; lerltehiM at aitramitiea Mill pteaent in miiaaa pita. J" Miee and rata Mill; euinea |ii* in deep nareeria with eloar alatllna lwvmtli.nl Exposure was stopped ami tlie animals removed to fresh air, The miee and rats were dea*l. The guinea jug# took 25 minute* to return to tlieir normal apix-anniee ami activity. One guinea pig from this group tlietl within 24 hour* following vxjiosure. Tami.k I Ximiltrr of JIih in Diflercnl Croup* of1 Mice. and (iiincu Pig* Kxjmsed fur Th,, Mimiic* irr Varying foneriitrulinits of Vijfl Chloride in Air Vinyl Silwiilr oMKvnOklnm Mr< cni by in tr) 1A wnliwy MilMl Mice Kill ('.nine* pint Tolffl >9 10 M 3a 4H Tout 0/3 l.'S 3/3 -- /IS 0/3 0/3 3/3 -- 3/13 C/3 s/s 1/3* M> tm u/ta! M/M * A drla)nliliili aeeaiiad a'ithinX haw laUnwtoat Forty Pr Cent Vinyl Chloride: Only five j {tigs were exjmsed to this concentration, irritation won* immediately apparent. Ml incoordination np|**an*d within seconds, -`j five minutes nil the guinea jrig* were ut with sknv slullow hmithing. At the end exposure (irriod one guinea pig was dead oadj remaining four were in di*cp luirvosis. Tbessf vi vim tixik 30 minutes to return to their apiniinuiet; nnil nctivity, Imt one died withia'i following 24 hours. Tlie mimlier of dixith* omirring in difife gronjMi uf five Ulmmtory animals exposed; thirty minute* to vamng eom-entrations of" eliloriile in air is shown m Table 1. Pothologicol Findings Oroa* patlHklngieal auil hLstologieiit studies WfJ enrriial out. Tlie findings are summarized Control AnintnU: Tlicsi' animals showed:' gross nr mienweopie evidence nf damage. T< u per ('rut Vinyl Chhtritle: All t<"*t anif survived this e\js*wm*. They wen* sacrificed ti w.-vki* later. On gross exaiiiinatiou flaw was dern-e iu mii-v of slight liypemniu nf the k Tliis was less marked iu nits. Guinea pigs i no differemy from control animals. On histolc examination tin* mire showxxl viy slight en( nient of tlie pulmonary vtwr]*. One showwl di*gi*nerative etiaugej* in tlie tulmlar liielium uf the khlis-y with hydrojiic swel Tlie nit# sliowed slight congestion of tla? capUl i> in the lung, lyings in the guinea pig were: slightly linin' hy|>crvniic titan thnse nf the coat auituuls. Tu'cnty Pt r Cent Vinyl Chloride: One me died as a result of 30 inimiUw exfssujn' to mncciitratioii. Ihilmonarx- <xnigj*sti<*n waaend* ou gniKM exaiuination. Microsiar|)H*nlly, there 20546003 Industrial Hygiene rtiC"rUvinciit of the hi jKii *>y areas of atcl< jl.. kidneys show ^lunai'"^ ill tlie cpi(h* Itul**1*Tlie test ittiima]* S jjnrifi'axl in two we congestion of the luu; Init it was more mark in the guinea pigs. F ({ciict' of inilniotuin' Utah. Some fatty ini jii.-- of imh' nit. AU o' IHSinal. Thirty Per Cent Vi tkm of the snimals \ f\jisiif\' revealed c* hcntorrliagir anus, 1 rhowisl rongvsttun < ene guinnt pig deatl there w* marked t hemorrhages aik) tls friable. Tlie micnm j,:-h died inrliuled jm: ;oooary hlocsl ve riug- s in tlie lungs.' tupcriicial desquam; gestioti was also v\*i uf tin* mice and nit whieli liad the deUi\ ik'gi'iK'mtion of tin section* stained wit Tls* four survivii tw.i wix-ks later. N - i>nT*-nt with h h -,.* i-aiH' there w intittmtion. '. cave the apjiesRinfat wu# demonstrat forty Per Cent guinea pigs 'X|ssi luring tlie exiiosui Ipiiii>. "riie two wl of tlw lull) W.miiiiatioii. Tliis * examination i tjjp*ar:iii'C of U* dcuumslr 1'lie tlina* survix Iwii week* later. ^ with hemorrhage and microscopic e the iniehinil cpitln Patlwilogiesd sti 'rain, hwirt, *|h* thi* eves showc*l 1 animnlif <lyin; X .. i-fi control* :u BFG03838 T Industrial Hygiene Journal m ii .rgemcut >.r 11 h* Musi vessels in the lung with l>. : liy areas of atelectasis iitul minimal edema. Hi. kidneys showed minimal degenerative in the epithelium nf tin- convoluted tuImlrs. The test animal* surviving this cxjxisurc were sacrificed in two wvk*. On gmx* examination, congestion nf lla* lungs was pri'xcnt in till |H.*ciu*, 1ml it was mom marked in the mitt' and rats than m l he guinea pigs. Histohigirally, there wai evi dence <{ pulmonary congestion in c.\|xixt uni* in1'- Sonic fatty iufiltnition was present in tlie h of oik* rat. All other tissue* studied uppearud Illl.l]. Thirty /Vr Coil Vittyi Chloride: Gross examina tion of tlie animals which died as a result of this c\]>oMire reveah'd congestion of tlte lungs with licinorrluigie areas. Tlie mice and rats in addition dvoml congestion of the liver and kidney*. The oih* guinea pig dentil was delayed. In this animal then' was marked congestion of tlie lungs with i.-morrlinRcs and the liver wii* distended and very ir-.-Mc'. Tin* microscopic changes ill the animala v.mcIi tilt'd inrhxlcd marked engorgement of the puimoiutry 11<hhI vessels with edema and hemor* fliagc* in the lungs. Tlu- trachea of one rat showed *ii|Tficial desquamation of the epithelium. Con* ir*-tiou was also evident in the liver and kidney <1 the mice and rats. Tlie liver of tlie guinea pig which liad tlie delayed death showed severe fatty i'gcnemtinii of the liver confirmed with frozen -Inins stained with Smlan 111. The four surviving guinea pigs were snrrificcd i weeks later. Marki'd pulmonary congestion - present with hemorrhagic area* and ctk-nia. I:. ..nr ease there was evidence of ixtondury hoc* t-Ttal infiltration. Tlie liver in tliesc guinea |tgs gave the apjx'amncr of fatty infiltration but no fat wa* demonstrated no frozen section. Turfy l`rr Coil Viiif/t Chlnriitr: One of livi' .uiiii-h pigs cc(xs<-d (( this eniieeulratioil ilk'll 'imnig the ex|MnMirv ami :nntIwr died within 24 hour*. Tin* two whieh died showed marked coni' Oioii of tlie lungs with hi iiHirrlmges on gross mutation. Thi* was also evident on micro* i' examination. Tlie liver of one f these gave a|i|H'araiie' of fatty infiltration, Imt no fat mid Is- demonstrated on frozen section. 'Die three siirviviug guinea pigs were sacrificed twn weeks later. Marked conge*tk>ti of the lung* with hemorrluigc was evident on Imth tlie grim and microscopic examination. In one guinea pig, dn- tracheal epithelium was completely a IwentPathological studies which wen- made of the 'f .iii. heart, s|ilei'ti, adrenals, lymph nodes and civs showisl no dilTi-naiei* liotwoeii controls I animals dying as a result of cxjxjsun.' or Imitn control* and tlie surviving animals saeri- linsl two wis*ks after expomm*. Them was a tendency for the Mood Mi remain umiotted in the animals dying during exiMtsun-. Tliis feature was nobst in the two liumaii fatalitk'S mentioned enrtier hut it is not a s|>ecifir din meteristic of vinyl chloride. Discussion Tlie rvftfxnisc of guinea pigs to infmUition of vinyl chloride was similar to that reported l*v Patty, Yant and Waite. The guinea pigs in our study, however, tolerated a greater exjxwiurc dur ing tin* ex|M>rinu*utal period tlum cither tlie mice or rats. Tlie result* in mice agreed closely with tltosc rv|>orteH by People* and Leake, Rat* were similar to mii-e in tlieir re|>onse. The pathological cliangvs in animals which died os a result of exposure were mainly those of vascular engorgement of the lungs with hemorrliages ami edema. Tlie severity of thesis changes varied witli tlie severity of cxfwsuix'. In tl higlier eoueentratious, imlmmuirv dumgv was marki'd with severe damage to tlie tracix'al epitlH'liuin. Congestion of the liver and kidneys also oreurrvd in test animal*. These cliangc* are similar to those reported bv Patty and associate*. Evidence of pulmonary congiwtinn was still present in surviving animals sacrificed two weeks after rx]xwurr, Putty ami associates reported tliat Sileh rlianges laid disapiienn'd in almit eight day* Degenerative changes in tlie tulnilar ej>itlclum of tlie kidney wen' noted in one mouse living os a result of exjssuire and in oik* mouse sarrifin'd two weeks after U-ing cN|xwd. Such cluing)1*, Iwwevcr, wen' mininud mxl ixit hIhiwu by other animals in tlie group. Otic of tlx.* guinea pigs with delayed death fol lowing cx|xmirc showed severe fatty infiltratxm of tlx* liver. C'hnuges suggestive of fatty infiltra tion wen* oliservi-d in other cx|mi| atiitunls Imt not eoiiliniii'd by frozen sectHMi* sbiintxl with .Sudan 111. Summary Scjmmtc gnni|M nf lalsjraton' nniiiuil* isnii- prising five mii-e. live rats and live guinea pigs were ex|m*ed in an inhalation cluimber to eonein- trations of 10, 20 and 30 |k.t cent vinyl chloride in air for 30 minutes. Ait additional five guinea pigs werv ex]H*ed to a 40 per cent concvntratiiiu for a similar {leriisl of time. Tlie rvs|)oii5C by vaeii of the sixt ies to tin's).' cmurntnitkius is noted. Inhalation of these relatively high i-onivntra tions prisluittl narcosis and ditttli. Mice were (he most sus<rptib]e with guiiH-u pigs considerably more ivsistant. ltat.i were similar to miev in tlieir 20546004 398 October,{ retpousc. iixjxjeum to ten per cent vinyl chloride in air produced deep narcosis in mire and rate but no dcntlir; 30 per rent concentration* killed mice and rata. Exposure or guinea pigs to 20 ]M*r cent produced deep narcosis; Imt tlircc of five guinea pigs survived cxjxwurc to 40 jwr rent eon* centration. An'unaU dying ns a result of exposure were autopaied shortly after death. Survivors and eon* trol animals were sacrificed two weeks later. Grom pathological and microscopic studios were done and tliesc findings are described. The principul pathological changes in animals dying from cxjwsuro were congestion of the lungs with pulmonary edema and hemorrhages in some, and congestion of the liver and kidneys. Failure of the blood to clot was also observed. One of the time guinea pigs which died following exposure sltowed severe fatty infiltration of the Hirer. Survivors sacrificed two weeks after exposure showed little difference from the control animals. Pulmonary congestion was still evident but liver and kidney congestion was not. References I. DAMitaca. II.: AarMmul INiinaw by V|yt i vnrv ( T-o Caw*. Gsaarfiaa U*4. Atmc. J. mINO). 3. Pxrrr, . A., W. P. Vast, ax* C. P. Waits: Ihl. S Cuior* Pin U Vapm to town Sw CtaMO CMi>pindi V. V(ayl COM4*. /***. H--Mi Mrm. (Aixnei ISM). J. Piarva,A.t<MnC.D.Uaa:TliiAM Vinyl Ckiorid*. J. fiamtilrt, 0.-SM USM). 4. Lxhmaxx, K. I. t F. Fim: T--'uim MuKil MmM, *------*--* by E. Kixf m4 K. T I Jr.. WiOtam a wakiM. fchhii (im. 5. Scwapm^xx. O.i enm by Itfcxw. K. 1. md t. ] I Ovraa. n. IL, C. 4. Cau, 3. C Kaum, as 3L 3. | vau: AmmWi XXVII. v'------ - with Vfcyi A*tmtrnmdm *' SSS Qttfl. 1. Caxx. J., K X. Inwm,3. F. Vise--. axxJ.C. Jm.: Aiailuk XXIV. CtmikMl fiammlM to Aw aaS CiiSm AetoRMtkfcy, J. Axa mrt rma ei: i L AumI XrRt if lb* CM</ fMXMr * FiMria fml tan. t--S-- : M.MJ.O. Cmd. sns (Maim MB). W Harm. D, K.: IMlk PiiH>rm to tba ttato Uot to PtatUto. Jrd. /. imd. Met ft; Mi (MB). ML Fi^aMVa. U. AO* E. a. OltMUM: Hytoato*' Ceatottow ia Nrrtarl Chtortto Tmr rkM. SS-m (fcawry mn. AbauatnS to Abe. * *Mf < M (July IN?]. Back Issues or AIHA QvAinxiar POR IS YEARS THE AIHA QUARTERLY was the publication of AIHA. then L in 105S it was changed to be else AIHA Journal with six issue* per year instead of four. Now limitation of storage space is forcing vis to dispose of all bock issues of live Quarterly. For individual issues quantities on liand vary from a low of $ upward. All issues except March 1940 (Yol. 7, No. 1) and June 1950 (Vol. 17. No. 2) are available as we go to press. Some issues are reprinted without cover. The cost is $1.50 per issue ($1.00 each wlicn more than ihrce issues are ordered) from Volumes 7 through ]$. From 11*40 to 1!*4G AlIfA Quarterly p|w\irod a* a section in Industrial Medicine ami Surgery, liowcver tlmse issue* of Hk*w attion.' luive been reprinted and are available a* a unit. Tlte complete reprint. Yols. 1-7, costs $10.00 to members, and $50.00 to companies or departments of government. Handsomely bound, complete set* of Yols. 1-1$ with cumulative index are available for $250.00 per set. Address all order* to: George D. Clayton, Executive Secretary, AIHA, 14125 Provost, Detroit 27, Michigan. (Rack issues of AIHA Journo), 195S to present, may be obtained directly from our publisher, The Williams k Wilkins Company, 42$ E. Preston, Baltimore 2, Maryland, at $1 $0 each issue.) 20546005 Acut* win Deport Introduction THE element tlial Crookes in 1SC1 b and isolated chemica Lamy. There are no thallium and its proi Tlw principal use* of 1 to it* rodenticidal pro) used as a depilating al*o used in the prod* glass ami in th* ti* eounters. An examination of mnnlicr of ptildished r tltnllium toxicity folio cidos* containing tliull sidcmble amount of w tin* depilating action lalxinitorv tininial* at trihution and excrvti iTI") ha* Ixiui rejiort * ' Remit].* I." have demonstrate Kiitainiiig sulfur act ar amte thallium jwisonu The work rqwrtcd b :n-utc toxicity of thallm oxide (TO) fiillmving ti comiMiuiwU to several : era! routes. Tin1 ingest poiiiid* was also iuve* iliriv months. Experimental Methods The two thallium coi taiiKvi from the Amor* On., Denver, Colorado leal Comment, Newa JKi-taU*). The purity relatively high (1KI.3-9 This ||*r m IjMfU ou il,. I'mu-d Suiv* Atomic Em UocfcMtar Kactxy I T