Document qk6MMnLeJ8pLej3YxwXmyz2XM

?9C . t ii i J > Oo o Xft! DEFECTS WiO VIWl CHIOS! K Hr. Larry CdennCs Health Services Cffleer 91p.h Cefetti ara.ncl Center for Oiscas Control l would Uke to address the question of vinyl chloride nonomer exposure and Its possible relationships to birth defects. If *><re 1: a relationship between vinyl chloride and birth defects, it*could te either ettegonic effect, prior to eonce?tlen,or a terattgenic effect after conception. Coe cf the first reports that vinyl chloride may be related to birth cefccts in humans wss presented In March, 1575, by Cr. Infante at the fork Acadorv of Science* The stud/ conducted liy Cr. jr.farte. tfcM with the Ohio Department of health, noted incrctsed rates frc~ ?7C to 1973 in three Ohio cesxnunlties where polyvinyl chio-icc slants were losa'.ed. Anomalies of the central nervous syster. -ere ;f greatest ccnccrn er.d nest of the excess was astri de; tt v*i city cf Paincsville, Chio. The concern was that resi- dA'tla'. *"i occupational exposure mght be associated with* Increased rates cf C.3 cefect*. At the Center for CIscssc Control, data are collected through th Sirth 2-i'octs Monitoring Program (S3.'?). Briefly, the B9h? is a natitral, hetp ital-based sys ten for monitoring Lne incidence of p'.r'r c-f-cts end other newbern conditions from hctpital discharge diagnoses; it ccisists of approximately 1,203 hospitals monitoring a ,-illisn blrt:.t per year from IS7C. The Z7"P previtfed data with which we could further examine the suggested increase in CHS rates in Ohio, V* identified two cities which hsd a polyvinyl chloride plant, end one SUM? hospital believed :? serve each ceruni ty. O.e hospital was in Pottstcwn, Pennsyl vania,and iftj other was In Paincsville, Ohio. Selected malformation rates for these two hospitals -- 1970 to 1974 -- were ee*o?ared with rates for their respective `states. 7*e rates seen In Pottstown, Pennsylvania. were 21-6 per 10,003, accexirately what was expected fresi the national BOM1 rates. Th# expected nunaer of defects ih Poir.ssvilie was approximately II. ?ne observed number of 22 cases was twice the expected. Ch the basis of this increase, an Investigation was undertaken in PalnesviHe. Poinesvllle, OMo.i* an Industrial city on Lake Erf*, rear Cleveland, with a population of approximately 16,900. There are t*e polyvinyl chloride plants located in Pairesvllla, They arc across the street from each otner nd about two and a half rills from ire center of the city, Che of then has been fn ojQfl* tUn since 19-9 and the otner since 1967. . The investigation was a hospital-based study and was United I to cases of anencephaly and s?fr.a bifida. The CPS' data were ccr> ! pared to birth certificate datj obtained frem the Ohio Cooprtrmnt | of Health, One additional case of ancncephaly was found, raxing a | total of 15 cases. J - The hospital records were reviewed to confirm the diagnosis ! and obtain otner denograpMc data. Ter -seh case, two centrals i were selected fren the hospital records; the first norral, white I birth before and after the case, since all the cases were wnlie. * The physician of each ootber In the case group was contacted I and permission obtained to interview the parents concerning their i past occupational and residential histories. The Investigation ; did confirm Increased rates for ancncephaly and spina bifida eonI pared to expected statewide rates. ! The hospital rates for ancncephely {14.1 per 10,000 births) and for spina bifida (21.2 per 10,COO births) were greater than two ! tires the expected rates, based on the 3JfrP state data, tone of j the 14 cases interviewedhad ever werked atcither of the two polyI vinyl chloride plants in Paincsville. One set ofparents could not be tocatcd, but hospital records indicated that they did not 1 work at the plant at the tise of their infant** birth. > Among the 30 control parents, two fathers bad worked at a polyvinyl chloride plant at the tiro of their infant's birth. So parent in either case or control group lived within two miles of either plant. Statistical comparisons or distances varying from one srflc J to 10 piles of parental residence to the plant Indicated that there was no difference between the cases ar.d control. > , Local Increases In CHS and other na!formation rates, such as seen in Paincsville, are not unecenon. In this particular study, 1 no association could be found between VC and the higher rates of CHS defects. i t\ second and similar study was Just completed in Kanawha County, Vest Virginia, because of the continued concern abos/t the I teratogenic potential of vinyl chloride, 3DK? d*ta were again re viewed for all counties having a polyvinyl chloride pUnt end at least one 31V& hospital. f -In the.earller study, the selection was limited to cities with J only one hospital serving the entire cesnunity. At C2C, we Identi- l fled 17 counties in the U.S, which, here a polyvinvl chloride slant ftnd at least one 3CMP hospital, I. Four of thrift 17 countfei had rates fer CHS defects that were ; Significantly hither than riUI fer the u.5, for th* tie* period, "*7 *3 TS74. Two of the counties so identified had less then SO of total births in the BMP CM were excluded from this ` tv.'./, , The two remaining icsvr.tles with increased rates were lake County* (Ms, {?oines*ille} the sit* of the previous* study -- and iltnawha Ce-fty, est Virginia, where 90 percent of eouruy births we-e ranittred. In far*.`a County there were 59 Infants born be tween 1S7C and 1374 with CSS defects. The expected burlier, beset! cn y.S. rites.wes 37. TASIE 1 ikcikhc: cf os HiircsrATicis m k,v;;u.\ misty, . VIP.GIIIU A!iO 7i IXllTW STWE5, ISCS-ISTS (fSATCS KH 10.CM TCTAt SIXTHS) 3D!? Hospital Bata b.b. Kanawha Co. Rate Cas Cats Vital Statistics Onawfu Co. Case Bate Confirmee Cases jtanana Co. Case lute The principal ejnje.-i of population In Kanawha Count/ include Charleston aid South C:,.'lettor.,wn'ch are located along the Kanawha f.iver which rear.<:$ through ire valley's hilly terrain. Tne Kar.twhs River Velio./ ij <i;wn for its chemical industry. There ere seven rajor chemical plcrts and scverel smaller cr.es within lo ei'.es ef Chirlcstcn, There is One polyvinyl chloride plant, lo cated in South Charlotte-., bordering Charleston, which began pro duction of polyvinyl chloride in 1535, I960 II.A. 1959 SJ.A. 1970 21.3 1571 22.1 1J7Z 21. C 1373 13.3 1774 15.4 1975 15.2 II.A. a,A. (12) 35.9 05} 51.7 (11) 30.5 (ID 2d.9 < 6) 14.4 (10) 22.9 (13) 35.4 . ( 3) 29.3 (15) 42,8 (13) 34.4 (13) 37.5 ( 5) 15.0 ( 1) 3-0 fU) (15) (1?) ( 5) ( i) 37.5 39.7 34.9 15.0 3.3 Two sources ef data were reviewed to Identify ill cases of cen tral fiervsjs system cifetts occurring In Karjwha County between January 1, 1770.ard Cecc.-ier 31, Cne source was a case list I97n1974 20.0 (59) 31.7 (4b) 27.2 7> 26.7 ing obtained fress the slrtn C-rfects lionltcrir-s Program which would list the uses occurring in the SIX? hospitals in the county. Tne s?;cr.c ssurco --as vital reicrd;. The cst Virginfa Oepartrent ef Vital Statistics provided all cases of Cs5 birth defects occur ring between January 1. 9?0.isd Dccesbcr 31, 1971. The ZDTC? rates arc given in tlie first coins* of the table. The McS Kanawha County rates compared to the U.S, rates are whit p-ocpied the Investigation. Tne last column gives the rates for The two lists were cc.*i>iocd ard the hospital records reviewed to confirm the diagnosis and the place ef residence, tar each con- Hrsed case, twe controls whose parents resided in Kanawha Ccvnty the tjnfimcd cases from 1973 to 1974. fiS yCv can see, 15/0, 1571, 1372 were the highest years, with the rates starting to ccdine. " ia 1973 and only one case observed la 1974. were selected frem vital recorcs.* These controls were the first nerrel, live-born infants whose certificates preceded and followed , a case. forty-six cases and their catched Controls were located end interviewed. Five eases were not residents ef Kanawha County at the tire cf conception and were eliminated free tne study, except The cates and controls were retched according to ronth of in calculation of rates, which are based cn residency. Close retch birth, race, paternal education, ard Mternal age. with the per ing *>as achieved between tne cases and controls tor paternal edtea- mission cf the local Avticiaes, all cases sr.d one raectfmly chosen tiot, ratcrnal ace, and tne Hul I Ingsheed Inccx, .rtiicn Is an Indica I l eor.trol were Interviewed. Ihe parents were told that this was a birtr* defret study and v<nyl chloride was cot roh'.,tones. The followirj Information wat pW.lned: history cf previous pregnancies five year residential history, pricr t? and Including the tire ef birth of tvc affected In'ant; and flvs year occupational history of toth parents, Including tr.e location of work end any possible tor of sccloccsnomlc stJtus. Reproductive history revealed that the tctxl nj/.ber of pregnancies were similar between ;iie coses and controls; 09 for the e-sc group and 4b for tne control group. The live blrtn percentages were oi;o very similar between tie two groups. Tne fetal death rates, which include spontaneous abortions anti stillbirtns, were 221 for cases ami 233 fer controls, crtcnicj) exposures. > j- i Occupational histories revealed that two cases and trt con trol fatners were eeplo/cd at tne vinyl dilorico plant at the time of conception, fathers of three addltlonel controls also had wori'.aj at the vinyl chloride plant on a contract basis and my have had possible vinyl Chloride roncear exposure. Sssm of tne mothers ir.'either the caso or control group had worked at tne polyvinyl VI /. \ t chloride plant, hot few wocon work In the vinyl chloride Industry* The residences of case and control parents, at conception, were plotted on count/ sujs and the distances fres the plant were "cal culated. Using a c-ni square test, at one mile Intervals, no statistical difference was ctserved between the cases and controls. Katceed pairs of cases and controls were also tested, using a ratcned'pair 7 test of significance, am no difference was ebserved. vr.ile no difference was chserrcO In the distance of residence fro* the slant, Infection of tie nap suggests tout. within the five nile area, cases were concentrated to the northeast of the river, and the controls were concentrated to the southwest. Frcsj-tnc pclyvlnyl chloride plant, X awl T co-ordinates were teterrlr.es fer the parents* residence, at the tloc of conception, for each ease and control. Casts and controls were then compared for h statistically significant difference in tnetr respective centers ef gravity, which is the Mar, position of the group. The only Statistically significant difference {?.02) noted was within the tnree nllc area, "here were 10 controls and 9 cases witnin this area. ?cth cases er.c centrals within the three nile area had a higher socleeccnonic index than those outside the area. Ho dif ference was noted between the cases and controls In regard to occupation or length of residence witnin the three die area. Cases did have an Interesting family history of birth defects. One case mother gave blrtn to two of tnc cases within tnc tsree die area. Arotwr case mother rud had a sister with spina bifida. A third csther ir. this case group had reported a cousin with a hear: defect, wnlle faalllal components do not exclude envirpnecntaS cause, they suggest a possibility of a genetic causa tion. . Atnstpherlc and environmental data related to vinyl chloride roncsor and other chenical caissipns In K&nawtM County are I id ted. Jor* cata were provided by the viiyrl chloride plant. These data have been collected over the past several years. Gi Oetcber the 1st, I97<, the largest single emission was noted and tnc VC levels were Measured In the community. The highest atmospheric levels were .1 and .2 parts per Billion. At tn*t tire tne wine was froc the southwest, and those levels were found to the northeast of the-plant, Additional data were available from the West Virginia Air Pollution Ccmissien, These data, gathered over the past several years, dealt with suspended and settleable particulate natter. They indicate Just the opposite of the VC r-easurceents. They in dicate that tne highest concentrations of the settleable and sus pended particulate ratter were to the southwest, suggesting a pre- doalnant wind direction from the northeast. In addition to those conflicting data, other data available cn wind and temperature data, coupled with the terrain, suggest this Xanawna County in tne Xanawna Valley is a veritable nixing bswt for an/ oris* tens. There have been identified ove- a hundred chemicals emitted into the valley. The effect of these clericals, alone or in cemij fratier, lj not kcown, and to attribute this case pattern witnin three riles to the effect of one cr.ericai plant is unwarranted. *7 In conclusion, both studies did cpnfin higher CIS rates than expected.during the early 1970*s." OS rates arc not significantly different froa the U. S. rates at the present tire, Occupational Msto-lcs in both studies revealed no difference between :-s case and the controls in possible work exposure to vinyl chloride ronorar. Residential histories shewed no difference between the case and controls when compared at varying distances from the poly vinyl cnloricc plants. However, in Kanawha County, we did see a difference in the pattern of residents for cases end controls living wltMn three Biles, ko explanation of this difference could be fume, aw: tne available data suggested no association with vinyl chloride rvsnoter. further plans are to monitor the counties identified earlier in too birth defect ccnitcrlng progras. vc also are gathering back data from Kjna-ha County to 1953 In order to detereine tho CIS rates far these years. . nn jv J- >*": *f -V" ; 1 ii$5 -] "iAls-';! frV.v:i +& , .:<*r : -?r , lyi-,., V: X V * li'-o-iv': * th people with the structural deformity, those fetuses, died.' Si, 'i 1 nave to loot at the structural dcforaities in relation m *.-icrj of abortio-; In the comunlty, which I Oid riot hear In t J think that when *e do these studies, they have to be done wf,.*s e-treordinary care because the stakes are cxtraordlnari!y H($h y:v:, ;'n net faulting tne study. I think that it represents a vV tericcs and important effort. I'm only suggesting that we Cr a let eere environmental measurements in the plants and out of tee plants. c do have to define all of the populations at high risk. e so -ave to carry out studies which will then look at the level at >.r:c- them papulations are affected. As I said before, >tiiere Is ns threshold for doSt of these things. At every level Of environ- rertjl cc~sa^inents * In the plant or out cf the olant -- sumone r^y he affected. So what we're really talking about when we do careful studies -- end this, I think, Is one of the approaches we can take ti this problem -- Is that wo have to look far what are socially acceptable risks. We have to look at doso response releticnships and try to Com up witn sot level in the workplace and in the ccrcrjnity which will protect virtually all of the population. If we do this, then we can look at the Question of the pregnant women as a very special case, and take every atterpt to protect her wltnout sacrificing her economic status and so on. 1 mink we'll have more to say about that kind of thing in discussion, but I feel that this really is what we're trying to grapple with today and teaerrow. ------- tEKTHMS. A.'BVgRS AMO CQtCSBTS K. CLARK C0C?S: Along with Dr. Carom, ! think we need epidemio logical studies concurrent with the actions that we are going to have to k<kc. We Rave found it very difficult to develop designs fer studies that we feel arc satisfactory, and I a* particularly interested in Pr. Wagoner's report Of fetal deaths associated with tzle exposures to VCM, bccOutO IRlI really has been one of the cost startling reports the; we have had. It was given to us in a very abbreviated fore and I an very interested in Just how the study was handled, and how data was obtained, C*. vWOfitRi This was a survey in which both male employees exposed to vinyl chlorido and unopposed rubber workers In the sane facility were questioned concerning the reproductive histories cf tneir spouses. The data were cnalyjed for potential interviewer bias, and none was found. The data were analyzed, as I indicated In che presentation, with regard to tnese individuals having two or more miscarriages, three or core eiscarrfagcs, or four or core trisearri* i-u ages. In order to eliminate potential bias resulting frees chronic aborters unassociated with the place of employment. The complete methodology of the study is includes in the paper which was recently published in Tne Lancet Kagatinc, where it is available for peer review. DR. PETER IKFA'iTC: I aa also concerned about the results f the CDC study of vinyl chloride, and about tne clustering on tne north west side of the plant. I believe the wind direction was predomi nantly fro* the southwest in this part of the country. In fact, recent studies by the Environmental Protection Agcney, in which they tagged chlordane Isotopes and spread tfcca for agricul tural purposes 1r Dallas, resulted in this chtcrdano being de tected in Cincinnati's water supply, for this reason, I think the predominant direction of the wind is to the southwest, and that is why I'm a little concerned when l see the clustering rear the plant, within the three-niU licit on the north side of the plant. Also, I an concerned about the case control oethod for the study -> looking at distances fron the plant -- given the mobility of the working population. For example, a worker who doesn't worie in the plant can work next to the plant but live ten ri'as away. Should a birth defect' cr some other anomaly be related t: this, It would show up ten niles away when, fn fact, the worker spends eight hours a day closer to the plant. Again, 1 think these are questions that need to be resolved. In addition, the nsthod of selection (n this'study requires exami nation. They looked at II cocnunlties, with vinyl chloride poly merization facilities, and four of them had a significant excess of central nervous system anoMlics. Now, at the statistically acceptable five percent level, you would expect five out of 109 cottsunlties to shew lignificant excess, end yet they found feur out of Seventeen witn a significant excess Of central nervous systea anosttHes. This 1$ of further concern because in two Of the cowunitidS, the rani toring lyitcd ascer tained less than So percent of tne Oirths. lot they were still able to identify a significant excess of central nervous systao anoaalles, I have tom Infoirotlon concerning birtn defaces in a conrunity that was not in tho CDC ocnitoring progna. The data was re ceived from tne Michigan Oe;artent or health, and it shews the Incidence of oirth defects in Midland County, Michigan, unere there Is t large industrial chemical complex, in relation to the rate for the remainder of the state. During the five-year period, 19/019?4. there was an incidence of Zl.J birth defects per thousand live births. That's compered t ?.5 for the state as a whole. So, AP00007509 i?ain, we set * repeated pattern of birth defects In areas'with chloride polymerization facilities. As ! said a yeir wge, this certain!/ does not mean that these c'.'.ervcttonj arc causally related to vinyl chloride. put as data cv.linues to cose in, I aa bcccaing pore concerned abeut It. -1. "I.'iKlEAj 7feae>. you very rucft. I think raybe Or. Edmonds debt to neite a reply. I might acd or.c thing mat would be helpful to The Ciivirowefital Protection Agency did publish a nsrogrjprt 1- tne sir sollvtten In the Kar.avha Valley. And 1 tlrir-k if yoa leak at that, r>ybc elevation right be Just as leportar.t here a UcJtion fcr a plant. That valley acts as a trough and you `.'ve r-c-uent inversions, end you have a lot ef elrno:: stushieg t -t>. t". forth ir. that trough. And year air pollution there should ' lev 11 ttle bf: different p; ttern than you would 'see if yaor t-.;cv'--V were quite level. K3. ! wsuld Just like to make a few comments. First of ail, '.'--tody rad? e cwrent earlier to the effect that these Studios 'varal no association with vinyl chloride. Its fact, these studio', t idto l rule cut such an association. 7h" *irst iliirg wc compiled was wind data. Dr. Infante said that vse yrcdcftinant winds were out of the southwest. Kanawha Vallt/ 1: i deep valley. The *er/ top of the valley is an airport, erd v.vi direction at that airport is out of the southwest, fc.wn in ti't .'alley there is a different situation. 'The wind direction Is dif'v-er* dur|*g the tics Of day, and time of year. In addition, you tar'Vt ascribe any one wind direction to any one part of the city. did try to ascertain wind direction a: the tiauj of con- ccptitn fcr both cases and controls. 7.` vln-.1 blew little more out of the southwest then out of th r.vrtheast -- about <2 percent of the tire versus 37 percent of CM t'ru. So the different* is very nlnlrwl. And difficult to assess. There is very tittle information on environmental pollu tants ir. ne vadey. There arc a lot of chemicals. j eentioned the VC Icvcis en one day they ceesurcd. That ene*day*s mcasurerints w-rc the only levels wo could find in Kanawha Valley. The levels were a little bit higher to the northeast, with the winds out of the toul-Vcst. The particulate and scttleable natter I told yew about has beer, osjsuftd ever several years. These tcasurceenta arc higher to the southwest, nc could be reflecting emissions frea other Industries Ir. the general vicinity. The environmental and atmospheric data were very confusing. Tou cawot Pinpoint wind direction to any one part or the county. As fcr sclcd.'tn cf the count lei, four counties with the highest rates were minified cut of the iv*iitccn. Two of them were eliolnatcd. In one of then, only three percent of the births were monitored. The other county that was eliminated was a county where 39 percent of the births were sanitored between 1170 and 1574, but whera the YC plant was not In operation until late 1972. So that ccsnonfty was eliminated, wnich leaves tr.c two counties of Palnesvillc and Kanawha. The next corrwsnt 1 would like to rake Is about the high rates In Hfdla.id. 1 would be interested in Knowing wtw: types of defects they are. DSL IKFAK7E: The data from Midland County, Michigan, shew total defects. ' With regard to congenital ancs'-ilies, thirty-four urogeni tal defects were observed, whereas only seven were expected; twelve heart anorviltcs were observed, whereas only four were ex pected; and fifteen cleft lip ar.d palate defects were observed, whereas five were expected. Those observations are highly signi ficant statistically. NS. PS0!>33: ve need to acnitor these ccuntles. In Kanawha Valley, * arc going to evaluate all birth certificates back to 1558. Vs still nave concern. DR. INFANTE: Well, the poict I was trying to mske is that the population study conducted in the Ohio coersunities with vinyl chloride palyiraritatisn fatuities dcronstrated a significant excess of birth defects. This study did not conclude that the birth defects were related to vinyl chloride. Cki the other hand, your study does not rule out the possibility. OR. GORDON: Tou cannot rule It out. \- OR. INFANTE: In fact, 1 as more concerned dm In that you identify four out of seventeen counties showing p significant excess. To n> that is a significant observation. KS.. CLARA SCHIFFER: t aa Interested in the technologies that are necessary to reduce hazards, and I have two questions. First, I would like to ask Dr, Corbett hew men It costs to install scavenger in an operating rera and properly vent ill And, second ly, I know Or. Cordon was asked to speak on plecercnt arc not an what Dow dees. But I went to take advantage of his being here to ask bln what technological changes Dow (s putting in to reduce seme of these hazards! DR. COR9CTT: The answer to the first question Is that It costs approximately $100 to install the scavenger device on an operating room anesthesia sachine. That is, if the existing remainder of the equipment is suitable for removing the gists fren the room. In other wprds, docs the oporattag room ventilation systca carry the gases directly outside, as Opposed to recirculating the air? If air is recirculated, an alternate form of exhausting is necessary. . i*" i :.. *; -- J * . ;r:- i - e-t ?/ <. i ij\ *- *