Document OvMe8yjeMvvZoDXxEbvnJ3Nv

pj tun, miuiwigmw LIA14196 miwwfttiiiitiii t frmm m tludw al HealHi lead todesSriee AesetMlea. bw. Wihf UJuJ. C'^<L>UJ Muxt 22, 1967 UAD BTOZBV AD 8AJBT7 B0U2TI1 Bo. 172 Tot All Mntxn of the Lead Industrie# Amo c lotion, Inc. Aa gtatsatot of Robert A. bbot, X.D. 00 Jaouary 19, 1967 at a Public Bearing Ip Berrlsburg. Pennsylvania V* bora a*cured for you copy of * scat Important aad significant stataaent that ve* given by Sr. Kehoe at tb* reflect of tbc Pennsylvania Health Depart ant at tbalr Public Bearing ao Proposed Abb 1ret Air Quality Criteria far lead. Tb* proposed criteria suggested that lead and It* ccapoimds b* Halted to 5 aicrograas per cubic arter of air, per 2L-hour average a* oea*ur*d Is the general ataospfcer* of tba atate of Pennsylvania. Tb* 5 alcrograa figure i generated by aeasa of an arlthaetleal calculatloo using data that tr. Kabo* bad Included Is his testlaooy before Senator Muskle's SubccoBltte# on Air and Water Pollutloo In Wasblngtoc In June 1966. Since Ur. Kehoe vas be* lsg used as as authoritative source of lsforsatloo to generate a standard for perslsalble aaousts of lead In the ataoepbere, and since Dr. Kehoe did sot agree with the use to which his data was put, Er. Kehoe felt It necessary to prepare a statement ihlch would glee his reasons for questioning the Judgaent of the state representatives la Pennsylvania. Bence, the statement which Is enclosed for you. The statement quite clearly above the reaeoos for believing that a standard idilch would Halt tb* aaoust of lead la the air to 5 mlcrograas Is unreason* able, tsmecessai7, and unduly restrictive. There 1* sea* Interesting tech nical detail presented by Dr. Kehoe which give* aoae Ideas as to tb* rational* for stateaenta that aoae of us In tb* lead Industry hare aad* about the safety of the general public at the present tlae with respect to lead exposure. For Instance, Dr. Kehoe points out that his researches, presently supported In part by HZRO, have shown tbst 10 alerograas of lead per cubic aster of air la perfectly safa for continuous exposure and that bis studies have proceeded to a point there huaan exposure is being aad* at a 20 aicrograa level. V* think this is a aort laportant stateeent and have printed extra copies for you. Pleas* 1st us know if you would like to have than. Vary truly youre, SaPitw attachasnt Don 0. Povlar I , .,u i !-> " wmmimmivmmmm&w*'wi:il'wMJ}' LI A 14197 ftatenent of iobort A. Xsboo, 11.D. at * Public Soarin' of tk* Sivision or Air Pollution Control 1 tbo Dopartaont of Health or the Conaonvoalth of Pvcna/lvanla in relation to Aabiant Air Quality Crltorlo with respoct to Partloulau Coapounds of UU i 1, Robert A. Kobo*, roprooont tbo KotUrine Laboratory, In tba fiopertoont of Xuvirooaeatel Health, of tbo College of ttodlolao of tbo Baiversity of Cincinnati, Cincinnati, Ohio. tlooo mj rotlroaont, ot slightly boyoad tbo convent locr.1 age, free tbo Directorship of tblo Laboratory and Dopartaont, la IS 11, J bay# coatlaaod to bo responsible for tbo Laboratory's exporirsantal progran on tbo behavior of -i load la tba hunan organise. Vila program, oarrlad out for oaay yoara vlth tbo 1 financial support of industry, is non ao aponaorod by a group of industrial organisations and by tba Halted States Public Boaltb Sorvloo. O for tbo past five yoara, tbla eork baa bsoa eoccontrutod oo tbo eotabllebcont of exiurla for arriving at a standard of Quality, with roapoet to tba ooooantratlon of load la tbo anblont ntaoopbaro tbat la tolerablo for buaaa beings, ebon talon into tba respiratory aystoe, along oltb tbat uhich la takas Into tbo allnontazy ' tract trom otbor aourooa In tbo gaaoral enviroruoeat, in particular, tbat contained 1 in our food and bovoragoo. I an bare to describe tba progress and tba present position of tboso Investigations. Another reason for sty oppoartneo arcs* tram tba fact that cartels lnforuotioo *1*1 1 provided in ,"ibllc Uotlnoay bsforo tbo Itiui' Coxalttoo In Caoblngtoa, D.C., sons oootbo ago, has boos, cade tbo basis f ar a calculatin'., by this agency of tbo Coaaoneoaltb of Pennsylvania, of tbo naxlr.ua concentration of load in tbo aabiont ntaoopboro, ehicb say bo oxoectod to bo coxpatlblo trltu pJbllo safety, tbo figure* given at tbat tiaas ooro not provided for tbat purposo, ani tba oooeoatrntloo of ntBOspborio load uhich vas obtained through their u a* la too loo. ! j ul h iu ip issjww^w 11 jyrpr.uosi^QB^ ' '1>j|i N 3486.01 yiB^pwpjappii . 1 j ftWi'Tflil '...^ '' i w |i>uaw.*iPiPPiWiffr``,M^wwaiKiP^|p^ LIA14198 -8 la a/ opinion, to be realistic, for tbs reason that a factor of considerable magnitude was aot taken into account In this calculation. 2 (ball return to this point Later. To reeuae the discussion of the experimental work ahlch hee provided the background for the preeent statement and thoae cade elsewhere, my aeeoclatee and I, la the Kettering laboratory, have been engaged for the plat twonty-elght yeara, la a descriptive eleeldatloa of the swtabollsu. of 1 .la husr-n aabject a esder a variety ef ooadltloaa. Theee Investigations he.-.' established the general level of the latake of load la the food and beverages eonaunod by healthy sale subjects, and la the output of load la their urine and facet, day 'ey day over periods of uoatha and years, under the ordinary ooadltloaa of Itfo, exeaptlug at the euhjocta have guarded agtlnct any occupational or other usasual exposure no load. To eertela of theae subjects, load la a aeries of dosages has hues administered dally, with thalr sals, vlth the elective ef doterulnlng the exteat of tic cbncrpvloa aad the excretion of lead, under thoae conditions, and the amount c. lend that accumulated la thalr bodies during periods of experimental ade1r.latrat.cn that ranged from L to 4.t years. As a by-produet of these observations, the maxima quantity of load Ingested dally In food aad beverages, ehlch vould result la a barely demonstrable Inc rapes la the rate of the excretion of lead In the urine, without any corresponding Increase la the concentration of load la the blood, ves determined. This quantity, approximately 0.( ag. of load. Ingested dally, resulted la the accuxulatlco la the tissues of tbo auhjecta of aa amount of lead of the order of 8 milligram per year, yroa these facts. It nay be taken that approrloately 0.8 nllllgraa of lead, oa the average, earn be lageated dally by the healthy Americas adult, without any risk, so loeg aa tbo concentration of load lu tho acblast atmosphare doss act exoeed, appreciably, the level the', it was kaows to be in the pertinent area of Cincinnati during that period (approximately 1.8 nicrogrami par cubic cater). mmmmm r -: mmsmmmm *immm r*Hh iiKMifc i Oir.ifclfc'Wn, fcTOilrfrfibi LIA14199 -* TU expertoaiits concerned with the Inhalation of load In tba itaoipbere, under tba conditions of tba laboratory, in Milch ve lava been aaiagad, lor tba r<il It years/have not boon quite no revealing of precise LnfornetIon, for too raaaooa, tba os/re potent of tba too rrnroiu llaa in tba fact that there baa boon no aatlafaotary oatbod far naaaurlnf tba extent of tba absorption of load froa tba^ respiratory tract, tba otbar raaaon ataoa froo tba virtual lapoaalblllty, oltbla tba llalta of raaaouable ootta, of nalatalnlng bnaon aubjaota oaotlnuoualy In an artificial atnoipbere, oltb respect to It* uni fora oootaot of load, Poe various raaaona, an experimental affort baa gooe about aa far aa It la practicable to |o, In tbla diroctloo, adtan tba subjects nra required to spend 84 boura par Peek (halt Of lhair tic*) Iti rveptratory ohaabar*. Accurate raseureneot of tba ultlobte degree of tba ratoatloo of particulate lead la tba roaplratory ayataa, following tba lnbalatloo of lead In tba a toonphare, constitutes tba oliUci* to a aatlafactory aatlnata of tba quantity of load avallabla for absorption. tba approximate quantity of tba alr-boraa load tbit ' la ratalnad la tba roaplratory eyeten during a dafinite period of expoiure can bo dataralaad by a natbod able* uo have employed at oaakly Intervals throughout neat of tbaaa experiments,(by measurement of tba load content of tba expired air and subtracting tbla amount Iron tba lead oootaot of tba air la tba ebanber). But tba ultimata degree of tba clearance of tba partlculata laad dapoaltad el tbla tba roaplratory tree, and amd subsequently to tba alinentary tract, by various nacbanlana, la not dataralnibla unleia it can be visualised In Ita proper quantitative relation to that vfalch baa bean Ingested vlth food and beverages. ^han eoa braatbaa vltbcut reiplrutory protection, la aa ataoapbera baavlly laden vltb particulate laad ooapouada of relatively larva alaa (1.8 alcrooe or noro la dlaaatar) laad appears In tba facaa In quaatltlee (nilligreas) that ataad out abarply against tba quantities (averaging 0.8 or 0.3 mg. par day) derived froo food end beverages. am* "fra i",nnimp S3? J.9l^ii|lui^PLpjPlPHi^!|W^^WPPj|WWW^PWP 4- 119*1^,1,111! ,HE IP,U'Wi UA14200 aaUHiOH lowrtr, tbs ooncc&tration of lead in tL air breathod tor ittonl hours per da/ ia only a too alorojrua por cubic seter, a la our experlaentt, ths quantities of load cloarod into the allcontar/ tract ara too esall to excood the variabillt/ ot U* tooal load (dua to ingested tcod), and alas too mil to bo Identified above the variabillt/ and tbo ua?Uii] error ot tba load la duplicates ot tbo lood ooneused troa ea/ to da/ - that la, ot course, too lull to Kara atatlntical significance^? it baa boon apparent, ia our respirator/ exporlaoate, that tbo oxcretloa ot load ia tbo urine ot tbo eubjoota (Cld la oxpootod to bare a well-defined rolatlooablp to tba aaount ot the absorption ot load troa tbo rooplrotor/ tract) baa not Increased, under Control led exporj.cental condition#, to tbo extent anticipated, bed oil of the Irta tT>tairrd dvrirr ti; rc-pirrtrr/ C/cle boon available for absorption. Col/ -vou-tbaa li.nro been as/ valid basis for ascribing susbors to tba actual >...ay. . w,,` 1,TM _ vc-.ia.r psrt* oi tbo rooplrotor/ tree. Elth'rtoo, la stalls* t.: facts observed la our expertnosts, wo bay* Bade so attcapt to expreex those pl/tiu--iiisal phoaonona is quantitative torso, but, Isotooa, _..a gjvoa then quell`.at. re rvuoinlilon ia tbo aiatesaat tbat "ocsoidiat loos tba* 51 por cunt* ot tbat in.'*-led io rut-- .oi It vho pulaooar/ tree aad lo available for absorption. Ia one lsetxnoe, I -----tel, rough!/, tbat approslaatcl/ 30 per cent at that tubalod, appoared to bo tboc.-b.i. X shall return, o little later, to consider the outcome ot tbs calculation referred to above, vben tbo factor of tbs clearaaoo ot deposited particulate load Is Included, according to tbo boot Interaction aov available. Koaazbllo, attantloa bould bo glvoa to o aoaao et ovoroooln* tbo obstacle preeeatod b/ the aoocaiit/ of resorting to intomlttent rather Una continuous raaplrator/ oxpoeur* la oar exparlaoBtal approach to the probloa ot load la tba eablcnt air. A oruaisl export.sent baa eatabllehod a basis tbat la believed tc bo sound. Previous experiments, concerned with tbo dnil/ ln*oatloo of eulticient quantities i e iU M ttlihr-i i n JUg u U0JUI1IIM qpnnw % t I LIA142 01 imwfttr' i irr~riiiAifi^inr> iiiiiir^J -inrr^r frr^ irwiM^rTfinrri^^^^ -,.-^.^-^.-1^-^ ~ ,-iM f- III i M i iO, Si -- eniuMBaii mijtu le u il M IB edai n e o n of lead with Mill bad shewn that tha rata f tha axeratios of lead In th# urine, and tha oooeontret ton of land In tha blood lne;aaaad at a substantially coaataat yearly rata (with aaaaonal and athar variations within tha year) ever tha entire period af tha adalalatratloo of load la thla canoar. Is contrast, tha oxpertsestal Inhalation of load, ae a temporal aahadula aInulatin* that af tha Industrial weak (IT.I to 40 hours par weak) resulted la a fairly steady increase la tha output of load la tha urine, aad la tha oooeentratlea cf lead la the Hood, over a period of approxlastely Id weeks, at which ties a plateau had baoa ranched (la tha levels of load la ttrlaa aad blood) which rsseised ir.chtrcod thsroa.'tsr, until the experimental exposure was altered or toraiseted. ntl Cisee recta la Bind, aa JS* Imtal tM <lfcitne<i aad eorraae out wmerexa two perseea, la parallel respiratory chambers, ware subjected to tha lnhalatleo of a suitable oerpooBd af lead (tha eesquloxide), la flaa dlsporaioc (aaaa dlaastar 0.03 dcroa) la tha etaoephare of tha chasber, at tha level of ISO Blcrogroas par cuhlo aster. Tha schedule of exposure was Initiated at 10.3 hours per week tor 1C weeks, aad expanded stepwlae to XI,' 31.3 aad 43 hour* par woek, during three additional periods, each of which was IS weeks la duration. The result was a aeries of plateaux of graduated height la tha concentration of lead la the blood (aad in tha uriiw), ee that a line connecting the average levels of the auooesslve plateaux continued upward at a ualfora slope, aad eould ha extended at the ease slope to 1C8 hours per week. 3y suok Beane, a reasonable approxlnation to the effeet of ocotlauoua exposure eould be arrived at. Proceeding froa thla background, a further experiment was carried out, with new experlBwntal subjects, at the level of 10 alcrograas per cubic eater la the ataeaphere of the ehacbers. Coder these eondltloas, thla eoseaatratlea of lead la tha ataeaphere failed to evoke a definitive Increase la the output of lead la tha urine, or la tha eenoentratloa of lead In tha blood, of tha subjects, at any tins la tha oouraa of a schedule that extaaded la a graduated aeries froa ppp nwavniaep^L j .u j w j j ,. i miiiii wum wm I M l 111 LIA14202 T-* 4gWrr-i:~:- - ^1 -7f^ -ft - Mb* .-'WW 10.ft through T3.8 hours par wash. Tbs sxposur# of tha subjects vas tsralnatad at tha lattar point, sines thers was no hope of demonstrating a gradustad tneraasa la their raapoaaa. Aa additional experiment was then Initiated at tha laral of SO aiofojraa* of load par cubic aatar uadar otbaralco comparable experimental ooadltioaa, Thla experiment la now under on,' but lu ut rocchsd tba stage at which any pradietloo aa ta tha prcbib.a outceac oaa be nice. Any aatlaata of tha tolarabla oneent.-ciion of load in -n ambient air, that altht be'made at thla tlna, through - caleviction of tha t7>* roi'orrod to nhova, would bay# to ha highly tootatlro, la our v_ev, especially sinne experimental evidence way ba axpaotad to ho forthcoalng within a reasonable period of time. It would oooa to ho logical, heoaror, aa suggested don, ~i reprensntta5 tha laaodlata altuatloa to thla agoacy of tba Coascawealth oJ ^asnjylwcnia, to aako uaa of tba method of calculation oaployad in arrivisg at tha figure of ft sierograaa of load por cubic b o tar aa tha upper tolsrcblo Unit of tha ccnoont:_tion of load la tha aablaat air, (reference la aada bora to tha too lottara of Victor S. Snesman to Robert A. Kehee, of Decosber 13 aad 30, 1006). In to dotn;. It la appropriate to introduce tha factor ehich appears, on recant evidence, to have raaaonahl# dogree of quantitative validity. Attachod hereto la a chart, Tahla 1, darlvod frea a publlcatloa that baa Just ocaa to band. In It, tha rwferenoa to tha publlcatloa la given, aa azw alao tha data obtained tharafroa that art partinant to our experimental conditions. Tbaaa data have boon employed, In round nnnhart, la tha calculation of tha tolarabla concentration of land la tha ambient atmosphere, aa follovt: (1) It approximately 10 par cant (la tha chart ft.S) of tha laad inhaled from tha atwoaphera la our experiments la avallabla for absorption trow tha respiratory tract; (3) aad It aa additional 10 par cant of that deposited originally la tha respiratory tract and than uorad Into tha allesntary tract la absorbad from tha alimentary tract; (3) tha figure thus obtained now tuna cut te ha 18 nlcrograma u wiw iiiai ju u.i niiauai ij ii i LIA14203 T- per euble Mtr. * Tbs (lgurw >0 obtalnod abovo la not naoesearily or avan probably correct. gxpaiiasntal svlds&oa la required (or Its verldcatloa or correction, aa tbs eaaa My ba. It baa, however, a rational baala (or Ita derivation, and, aa such, It would seen to ba tba boat estimate that can ba o((arad aa aa approach to a aul tabla orltarloa. Coe otbar point requires seme ooaaldaratloa hara. A (actor which aatara late tba promulgation of a standard o( air Quality, with raapaot to load la tba ambient atmosphere^ le that of tba allowance that should ba made (or tba variability la tba susceptibility at porsoos and groups la tbs composition o( tba gaaaral population, (bars la no aeeaptabls convention that ha* tVr s'lgVtrft srtlfsl to this physiological problea. A considered opinion My aev bo based reasonably on tba erldeaoe obtained by clinical observations In association vltb Quantitative assuraasnts at environmental conditions la tbs lend trades sad in tbs community centrally, sad on tba physiological and clinical responses at large nusbirs at persons to aucb environmental conditions, lech observations, cads only In tbs eonparstlvsly recant period within which analytical (cellules have bsaa equal to tba task (approximately 30 years), bavo daaosatrstod, boyend any reasonable doubt, that human susceptibility to tbs eilects at tbo absorption o( lead varies only wltbla well~de(lned Quantitative llclts at ihuorption. H(or example, tbo Industrial oavlronnsnt (In tbs lead-using Industries) Is atiziMzed (althlully below cartsla established hazardous levels, and whan si: c( lhs conditions under which tba employees work are so controlled that their absorption o( load doss not exceed tba accepted level at ea(ety, no toxic a ((acts at th.' bind are observed at say tins la any parson during tbo most prolonged periods at on?loyesat that American Industry affords. Similarly, tbs occurranos at lead polaanlng wltbla tba general population, among children and adults alike, Is always associated with lavela at lead absorption (aa shown by tba lead oontent at urine or blood or both) which have been established, in extensive experience, ss dsngorous. WlBW? adMMa>*^hagiatd*i^a*as^^ $ LIA14204 :.;ie^ga...^^'-a^o. Converse!y, la our sxperlancs, ao peraoa suffering Iron load poisoning bae been found, at the onset of thl illness > that la, In laoadlato tenpoml relationship to tha oxciting factors la tha production of uc\ nines* sho haa not given \ duantitetlve analytical evidonce of tha ahaorptloa of daagoroue quantities of load. I {By euch evideo#, bora, la aaaat a general level of exorotlon of load la tha urine, aatahllabad through adequate sampling, o* at laaei 0.15 ag, par day or par liter, or a ooncentratioo of at laaat C.Ot " 0.01 =;. par 113 grate of ubole blood, aa dataraload by pathoda of aaalyala aa sensitive aad precise aa tboaa oaployod w la tha Kettering Laboratory.) Such evidence aa --obtained by a ausbor of axparlaaood Investigators during tha pnet thirty years, baa demonstrated that ) -M bus1"* suaeoyMbillty ta lead ;clw.-.:;.w aa. ...r.a i.wif, oftoa, at aad above a "I certain Laval of ahaorptloa, bat sot belou It. and that tha margin batsooa tbs daageroua lcvol of abaorptloa and that uhleh la aaaoclatod tr.th ordinary ocvlrmaactal ooodltloaa la the Arerleaa onoaimlty, (anarally, la aaplo for tha purpose* of differentiation. Thin la not to any, arbitrarily or dogantieally, that thare any not bo eeae poraooa ulthla tba total population, shots ability to handle lead, physiologically, haa baas lapalrod la soaa significant aanaar. Such pereeaa oust, lodaad, be few, aad there la llttla roaaoe to fear that any auch paraoaa oould be affected advaraaly by tba general levels of oavlrooaaatal exposure to load that are under dlscuaaloa la this atatenant, there are still occasional source* of exposure to load la tha oodern Aaorleaa oecauaity, that coed to be ellnlnated or controlled effectively, lo order to provwut the occurrence of lend poif>onlag vlthln tba seneral population, notably aaong young children. Such caeca, bovever, have no relatloaahlp la tholr etiology to the prevailing or laalscnt level* of the general onvironaoatal expoaure to alr-borae load. Dated! Tobniury 1, 1007 i. tw----w---g---n--)-p--w--g--j-j-i-.-'.-e--m------111 w mmw p 5: ' 'i-.  TOT1 M mkxjKmia -0- '--.* -i* - "'- T1BIB r The ICJU+ Lung Cynaalca Eodele* predicta th following tor partldaa of load actquioxida u defined belowi Beeaured acts dlaaeter m 0.01 aleroa Oeoaetrlo atandard deviation m l.Ooo* Approaiaate denalty m Count radian aorodyaajaie dlaoeter V 0.IS oicroa Itaaa aedlaa aerodynamic dlaaeter V 0.39 alcrca ,% Of That Predicted Dupoaltlca tabalod Kano-pharyngeal . Trochee-bTonrMiI T.O B.e Pnlanaary 40.0 Pradletad Claoraaoa (61to) (galt-tlae) Blood 0.1. Tract Maad O.Z. Tract 4 ala. 4 ala. 13 ala. 10 ala,. 0.1. Tract 94 hr. 0.1. Tract 00 day Lyaph -blood 00 day Blood 00 day S Of That Inhaled 0.T 0.9 6.4 T.O 10.0 14.0 0.0 0.0 Total Depoeltloa 66.0 % U Xxhalod Air 46.0 at oqulllbriun 0.6% la clauad to blood 46.6% la olMiad to 0.1. tract Istonational CoocLlaaloo for Badlatloa Pretootloa. ** Developed by Tank Group on Lung Bynaalca for Ooaolttee II aa publlabed la Health Fhyalca. Vol. 12, Xo. 1, pp. 179-306, 1066. oo Tbo aodal aaauaaa a larger (aontrlo ataadard deviation. Tor tbla partlelo *l*a, tbo aodal would tbua tond to ovaroatlaato dapoaltloa. iiimiW.lijUUi Niff W