Document G5ZYooJnJ948VorjkxZKOwEnV

Mortality Among Employees of PVC Fabricators 6/"2- RuvtiVD JAHURtCD u*t.barr Leonard Chiazxe, Irv Sc.D.; William E. Nichols, Ph.0.; and Otto Wong, Sc.0. A eroif'iectlonal mortality study of 4,3*1 deaths occurring among currant and former employed of 17 PVC fabricator* during 1964-1973 It pretented. The objective* are; (1) to Iden tify any angiosarcoma death* among the employee* of these fabricators, and (2) to examine the distribution of death* by cause. No angiosarcoma deaths were found among the study group. Sex-race-ciuse-ipectfic Proportionate Mortality Ratios (PMX's) were computed, using the corresponding U4. mor tality as the standard. Among while employees, there appears .to be an escet* In total cancer mortality, particularly that of the digestive system. Observed deaths were found to exceed the espected In cancers of lha breast and urinary organs among while ferrule*. Deficit mortality waa observed In cirrhosis of liver among both male and female white em ployees. The January 1974 disclosure of three deaths from angio sarcoma of the liver in a tingle vinyl chloride polymerization plant and the attention focused on this new occupational disease are well blown. A significant amount of information from animal ex perimentation and observation on humans engaged in the produc tion of vinyl chloride followed.' However, there was no informa tion regarding the possible adverse effects on employees engaged in polyvinyl chloride IPVG fabrication, where potential exposures were thought to be low and to result from the release of unreact ed monomer trapped in the resin. This issue was considered of great Import because of the very large number of workers believed to be engaged In fabrication. in March 1974, representatives of PVC producers, who are membeti of the Organization Resources Counselors (OHO, Oc cupational Safety and Health Standards Croup, contacted. ORC about the feasibility of a study of health risks to employees work ing with vinyl chloride and polyvinyl chloride. Since the National Institute for Occupational Safety and Health (MIOSH) was Con ducting a study of vinyl chloride and resin producing employees, the scope of the proposed ORC study was limited to employees of from the fiwkJon ef Sinn, and tprdtmioloay, Oepvtment of Community Mudmine and International Heakk. Georgetown university School el Medxine. Washington, DC 2000? Or. Chiase and Woegi and OrganlaaMA Hasuucei Cow- scion. Inc. Wasidngtan. DC ZOOM Or. Nichofci- Journal of Occupational Medieine/Vol. 19, No. S/September 1 companies engaged in the fabrication of PVC resin Into finished products. A number of alternative study designs was considered,' and it was decided that a proportional mortality study would best meet the urgent need for information. The study concentrated on deaths occurring during the ten-year period 1964-1973 among ac tive fabricating employees plus retirees. Since it was not possible to identify those employees with onfy vinyl chteride'exposure, the study focused on deceased employees who worked anywhere in those plants where PVC fabrication was carried on. The primary objective of the study was to determine w Nether or not any angio sarcoma deaths had occurred among employees of the fabricators under study. A secondary objective was to examine the distribu tion of all deaths by cause. The relatively few producers of vinyl chloride monomer and of . PVC resin are generally medium to large companies. PVC fabri- Cators, however, range from large plants of major companies to very small job shops. Even in a large plant, there may be few em ployees who are in the vicinity of PVC resini. The range of conji-- pany plant size and number of exposed employees help to explain the wide range of estimates of total employment dependent upon PVC resins. Fabrication Is geographically disbursed, with at least some operation in almost every state. Typical fabrication products Include coated wire, upholstery fabrics, floor and wall coverings, pipe and other construction materials, toys, recreational equip ment phonograph records, containers and container lining and a myriad of novelty items. Since Ihe fabrication of PVC resin into finished products Is often a part of diversified product lines in a plant, raw materials other than resin are utilized, Thus, employees may be exposed to toxic agents other than vinyl chloride. Conse quently, In the current study, it Is not passible to isolate only the effect of vinyl chloride Some departure* from expectation may be due to exposures lo vinyl chloride, to one or more othei agents, to some combination, or to employee characteristics other dun occupation. Materials and Methods The decision to focus on a cross-sectional mortality study rather than on an historical cohort study dsrlved from several con siderations. First, the primary study objective was to determine relatively quickly whether or not any angiosarcoma deaths could be Identified among the study group, and this was best ac complished by examining causes of death among relatively tecent $23. AP00006968 ' C*., put ten years} decedents. The desirability of Identifying art historical cohort for followAlp was recognized, but it was deter mined that it would not be possible to identify clearly and com pletely the necessary cohort of workers within a reasonable period of time, if at all. As a consequence, this study is based upon 4. Ml deaths which occurred during the period 1964-1973 among current or former employees of 17 companies engaged in PVC fabrication. A total of 95 plants supplied data on all identifiable deaths since, as was mentioned earlier, it was not possible to iden tify those employee* with only vinyl chloride exposure for the study., In order to be Included in this study, a deceased employee (ell into one of the following categories: (1) employee died while ac tively employed. U> employee died after retiring from the com pany with retirement benefits, and 13) employee died after ter minating employment but with vesting in a company-sponsored life insurance plan. Deaths occurring among former employees with less than the number of years necessary for Insurance vesting were not included in plant records and were, therefore, not available for this study. An attempt was made to compensate For at least some of the "leakage" due to employees leaving the industry prior to the time they were vested in any insurance program by using the following procedures.- Once death records for a given company were iden tified, death certificates were obtained and separated into two groups as follows: HI all deaths with cancer IICDA 140-205 up to 1967; ICDA 140-209 for 196B on), or liver disease IICDA 580-566 up to 1967; ICDA 570-576 for 1968 on), or suspected Kver con dition mentioned on the death certificate; and (2) all deaths from causes other than cancer or Kver disease. Death records men tioning cancer or liver disease and giving a hospital as place of death were segregated and sorted by hospital. Where there were several death records far e single hospital or several hospitals in the same area, arrangements were made for a Registered Records Administrator IRRA) to visit the hospitals, review medical records, contact the hospital pathologist and review pathology records to determine whether there were any angiosarcoma cases In the hospital's pathology records. If so, an attempt was made to deter mine whether or not the angiosarcoma possibly could be related to vinyl chloride exposure. This procedure enabled us to identify whether any employees, who hid left the Industry prior to vesting In an Insurance program Bid remained In the local area, had died from angiosarcoma of the liver. The hospital Inquiry procedures turned up five deaths from angiosarcoma of the liven according to company employment records, none were employed at any time in PVC fabricating plants. These deaths were reported to 05HA, NIOSH, and CDC for inclusion in the nationwide angiosarcoma survey. Death certificates not mentioning a hospital as a place of death required an additional step to determine whether death occurred in a hospital or if a recent hospitalization had occurred prior to death. The certifying physician was queried by mall for in formation on recent hospitalization of the decedent and whether there was any indication that he or she had canceror liver disease. Additionally identified hospitals were contacted as above. Originally, it was planned that death certificates would be ob tained from Ife insurance carriers. In practice, both company and life Insurance records were used because of record retention prac tices and retrieval problems in die insurance carders. All available death certificates were examined by a trained nosologlst for men tion of angiosarcoma anywhere on the certificate, and no angio sarcomas were found on the death certificates. Underlying cause of death was classified according to the eighth revision of the In ternational Classification of Diseases.' Over the ten-year period under study, plant size was found to have changed drastically In many cases. In one Instance, a plant employing 300 employees In 1973 employed fewer than 10 in 1964. At the other extremes one plant employing 5,000 people in 1964 had only 2000 In 1973. 5ome companies had gone out of business. Such developments show not only the rapid changes taking place but also the difficulty of determining average industry employment. The 17 companies covered in this report ranged from singte plant small companies lone with 70 employees) to multiplant luge companies lone with over 7,000 employees). . Average number of employees clustered between 300 and 500. Although total employment is difficult to determine precisely. It te estimated to have been between 65.000 Bid 70,000 at the end of 1973. Snce the population at risk could not be determined, mortality rates as measures of risk could not be calculated. Rather, results were summarized in terms of Proportionate Mortality Ratios (PMR) adjusted far the age distribution of the study group. The PMR uses relative frequencies of specific causes of death by age in a com parison population to obtain expected numbers of deaths from that cause In the study population. Selection of an appropriate comparison population poies some difficulties since it would be desirable to have a cause of death distribution for a similar group of workers dying during the same period, but not subjected to the factor under study. But such a comparison population was not available, and the study used mortality for the United Sates, specific for color and sex, for comparative purposes.1 Despite recognized deficiencies, the PMR .can provide clues on unusual distributions of causes of death where true rates cannot be calculated. Results Table 1 gives the distribution of deaths among the employees of the 17 PVC fabricators within each of the tan years. An increase In the proportion of deaths taking place In later years of the decade may reflect a variety of factors, such as an Increasing employee population, less complete availability of records for earlier years (e.g., In one company, there were no records for the first four of the ten year*), increase In duration of exposure; etc. However, there is no reason to believe that .any unavailable death records for earlier years would be concentrated in a few causes and thereby bias the distribution of deaths for those years. Tt1ai,t 1. -- DMrttatlM at Carta JUaMf BnptajMa at IT f-r -ZVC MMIm fa Oar el Paata, UM-Un.-'' - 1 Y*r * Qtft -1 196* S2S IMS MS 1466 400 1467 --------- 4 1461 499 1464 MS 1970 465 1971 471 197? W9 I97J <30 TM* 4141 'v 0 11 M U-5 101 14.7 . " 11J l M IDO 624 Mortality Among Employees of PVC febricatcrsTChialie, Nichols, end Wong 1 t AP00006969 about the same proportion as for alt U.S. white women in 1963. TUI* 2. -- Ofclrfartlea *f Outhi Amoitf fjn|*Mt dT 17 About two-thirds of the deaths for both nonwhite men and D WC Fabricator* by Cater and Sax. l*64-i7J. women were from diseases of the circulatory system and from t cancer. The numbers of deaths for most causes among nomvhites, n Rata - TgUI Cm aui FiMk ViilAHII however, are quite small making interpretation difficult and are n presented mainly for completeness. TeM 4U1 JOT ttl 2 Age-adjusted PMR* for white male and white female employees y d wait* UvmMftt { iMvm 7141 JZ4I toi KM ltd------ - --14 tit W 0 0 2 of the 17 PVC fabricators are presented in Table 6 for selected causes of death. There were no similar analyses for nonwhites because for nearly all causes, the numbers of deaths were too o small to produce stable PMRs. {Expected numbers of deaths have been calculated on the basis of the sex-cause-age specific 3. The distribution of deaths in the study group by race and sex is distribution of deaths among U.S- whites in 1968 applied >0 the. Si given In Table 2. Most deaths <647%) occurred among males. The total number of deaths by age among white men or white women jf vast majority 186.7%) of decedents were white and there were 268 in the study group. The midpoint of the study period (1968) was <6.6%) for whom race could not be determined. Table 3 showi this selected for the stand*d, since k is representative of the study V distribution of deaths by age. For both white male and white period and provides U5. mortality data coded according to the u female employees, more than half of the deaths occurred among eighth revision of the International Classification of Diseases, fx- K) those aged 65 and over (58.1% and 51.9% for white men and pectetf numbers are deaths for individual causes to be expected a white women, respectively). The corresponding proportions of In the study group if the proportion of total death* ascribed to a - deaths which occurred after age 65 bt the United States given cause were the same as for the corresponding U5. race-sex m population in 1968 were S9% and 72%, respectively). The higher group, while accounting for differences -between the age t* proportion of deaths among white women over 65 in the U S. distributions of deaths in the study groups and deaths for the >e population compared to the employee population may indicate United States. A PMR larger than unity would indicate that the 'P that relatively fewer women work to retirement age than do men. relative proportion of mortality from that particular, cause in the ie While the numbers of deaths among nonwhite employees are too study population is higher than would be expected based on the ot small for any definite conclusions, the distribution of deaths by 1968 U.S. mortality experience. Due to the nature of the data, for h, age among nonwhite men is roughly comparable to that for the mal significance tests and interpretation in probabilistic terms are total United States. deemed inappropriate. . Tables 4 and 5 show the distribution of deaths for selected In addition to the numerical value of the PMR itself, the ob causes by sex for whites and nonwhites, respectively. Among served number of deaths is also of interest The larger the number white men, nearly 60% of the deaths are from diseases of the cir of deaths observed, the mote reliable the PMR. There were two culatory system (ICDA 390-458) and 20% are deaths from cancer deaths of unknown age among the white males, one a digestive (ICDA 140-209). The corresponding percentages for the total U 5. cancer (ICDA 153) and one an unspecified cancer OCDA 199). population of white males in 1968 (midpoint of the study period) These were included In the age groups with the lowest relative were 54% for diseases of the circulatory system and 16% for can frequency for those causes, that is. less than 35 year* for total can cer. Digestive and respiratory cancers account for somewhat less cer and digestive cancer and 65 and over for other and un than two-thirds of all cancer deaths among the white males in die specified cancer. Such an assignment has a trivial effect on the ex study group as compared to about 59% of all cancer deaths pectation but is the most conservative way of handling these of among U S. white males in 1968. For white women, over 46% of unknowns, since It serves to increase the expectation (and hence jf, the deaths are from diseases of the circulatory system (compared lower the PMR) by the least amount. or to 57% for all U.S. white women trt 19681. and 39% were from can Based upon both the number of deaths and the value of the ay cer (compared to 18% for all U.S. white women in 1968). PMR, there seems to be an important excess in total cancer mor Somewhat over half of the cancer deaths among white women in tality among the white males in the study group. The distribution the study were from cancers of the breast and digestive system, by specific cancer site suggests that any excess appears to be con- ft 5 a # s- 5- S, J ng AP00006970  Tabh'4/^TowMtiwr* ttartfa iraTfafafa* wm Iwm Ewpltyra el 17 PVC hMeltan by lit Vhfti Oiilr, IKtltn.; Cm* * 0k9i . 'A; * 1 T *i t--rv ,V ' - Vieo* fab i .'.v'ji-Irtl ::'-4 kM fa fa- M*. JU! tot* U burs . r:' wn * inn n too00 J 140-2 >> . - w D30 HI son -i - fatal Cwiljad --2 15 (M l ` eso i Oipiliw fariaa lUflMk - fatTM : Lfa iso-tss - 2R III -4 *.. r"' 41 IU *. - 7J . iu J*r-- -r.-- ns- -m"- - - 1 ` (.43 ' S3 sat _j L24 L~t J23-^ in . HI 1 (77 .-n.**- 'iu -4 - (11 ., 0 v VO ... J * 9tipnfa| fattm iiuca- - 705- 1 -12 .tm-* : u> - -v . ' 1 SM ..- U rf... i fa*, tew** : --W: *' tin*, fa fart MWfd'W'F''*- " u *- .-U r>.*r-4j ' U9 $ fcmL * v 17* Y 0 41" 1 raz Ti fartW 44 us-:. i .MS i - ttfay Or|M in-in-. 31 141 It . ms ..Nt OtMr `.ffam faikrti '' - Ottir-1 UnpfaM-i m i Vfitttormt - X&m. 2QW. _ T ix-~e . ass Va-'-v tsr'^ in r rt-.aoo 9 42 ITS ; Ltt ,{ lafaria Diracs MMWg. 2M 19 on -t O.if'V 42 1J 11 143 i r fam* (MM . * CfetWory Sratan met Cafafnitw fattt " *' CkrtuH d Uwr sn . Sf.. - - ' 1531 J 1 * *219 : 47 " DifaejwJuid 1 thttoiftii ... WMi fafat krfVfcfa* ww - - . 7 in - MIS 231 ^7*1 I SO ^15 -: 1C2*- -j1 12* - 3 : 440 :i t : t'^SS. - oil ; i -3'' ; 440 -I T- ^ W II - *th.?`V r'-i '7J9 f _5mc4 ' ; H Otlw Cww 'OtaM U0W949 134 4.13 . (-32 40 123 - -2 0-33 : i v.-r . . -jj 'Ana - (U>ms^-L;tfwJr-Uaf-stKufi.w3f T4H 9. -- OWrtMtw V CiMk *m MkM Cauuc Anuf ^ twpleyfa* 17 NC ffartofa* 1* fai. fanfaK* Italy, 11(4-1173.1 . *4 j. * \\ Bkfa- /\ * ' fa d fatffc V . tafa. 'Jfa. ' S fa. " , An fa* m 10040 34 iuj v ` AH.ttttr* ' UHtt M . mt t 1S i face*! CMy urn Phtf>rK r*' 140-m ' '".V 6" -V *T PiSMthM ly>fai . 15W . ; - 72? . 4 UjC7 J ` llfa 1 3 ii!- 1 # ` ** *** : ' ' 193 T -- - : : M3 I - 44t * ' ikm % i,:. 1S4 - . 026 - 0 >J - IIMT v UnpiratBTSfsrOT 1 mio ... * . 1. 044 - 0 -] ' 7. 3J9 1 ,`t lung. . 1(3 v- Vr. >* 7. 1J* -* -- ' -r^ > fa Ctfki ' - +m SLr * -ToaoL fa kmaC"T' 170-174 i.r* s `i * -- . . 3 12JT1 ii Brat "f1* ' 174 * * 3 ` faftitM 1 1H-IV7 . Uriwy Ortww - m-;i9 . >* , -3 _ 232 , B } UI _ j 0 ! * Brfa t fatrt Otfa , fat** ^`rr-' * IS'M' S?- IFF"- r'-Duw 1 Ihwfart - 110. 1934*1 ,'r r iiftfpii... * - 200203; 20I4QS -' ^ 4 ! IfallTlH - ' 0f - > 2 *A .. 133- - 0 0 - V 222. . 0 0 .* ` Ml - -1 -- 4,11 i . Dbbtlis 24Q ' 2 1J1 0 ! , fiwri tf *' Cmfafay fan* * msi F -Ht-'-jjV " "ft. %`S." "4Utt CffaMii .y : 430431 " - is 1056. - 3 1250-1 - Cirtcn rt LW w,.faWtfa. - Chofaydfa, ' tMtmilit ' i 571 .* r ;*;'r - ; ' 574S7S ` - 2 U? ' ' y. -T v 'ifrr >r ..rff . " '0 sit ; 94 ; Araifa Sfafa* 4 Vicrtm - < ' dOM9 - .edJ*'*.'-** ` ' jj L ; iur ''a ki Acddlrt* Sukirtt QOMW Et50{45t 13 t.44 1 *.! 2 ML B 0 ! . 'AN Dtto Cam-* ; mm ^ , fair 'x?*-:'."7 jpriiT.':ia ir`-tr ** --"t ``t~-----~1- "-iirfir * -6 atm. 2 A * 'J, cen (rated In digestive system cancer, given the Urge number of deaths <31% ef aU cancer deaths). For each of the sites within the digestive system, observed numbers of deaths are greater than ex pected. Although, except for intestinal cancer, the observed num bers of deaths are small The PMR for liver cancer b rather high, but a definite conclusion is difficult wtth only six observed deaths. On the other hand, the PMRfor cirrhosis of the liver suggests a deficit in mortality from that cause. For white women, the PMR for total cancer appears high, as it did for white men, with cancer of the digestive system and, perhaps, cancer of the breast contributing a fair amount to the ex cess. Tht PMR* for individual sites within the digestive system are based upon small numbers but suggest an increase in Intestinal cancer. The PMR lor urinary cancer, though bated upon only 11 deaths, seems strikingly high and may be an Indication for further investigation. On the other hand, in contrast to the observation In white men. the PMR for respiratory cancer among white women Is very close to unity. Similar to the observation In white men, mor tality from cirrhosis of the liver seems to be in deficit but the corresponding observed number of deaths fc quite small Among both white male and female employees, diseases of the circulatory system account for a brge percentage of total deaths, in each case, observed numbers of deaths are dose to expected. There appears to be a somewhat different pattern among men and women for deaths due to accidents, poisonings, violence with the number of deaths somewhat low among men and high among women. There were 39 cancer deaths among nonwhite men, somewhat greater than expectation, although the numbers by site are too small for meaningful analysis. Mortality from cerebrovascular disease appeared high (PMR 2.111 but the Finding was based upon only 19 death*. Discussion The present study was designed with two objectives. The first was to determine whether or not any angiosarcoma deaths had 626 Mortality Among Employtea of FVC Fabricators/thiarte, Nichols, and Wong AP00006971  Tabh'4/^TowMtiwr* ttartfa iraTfafafa* wm Iwm Ewpltyra el 17 PVC hMeltan by lit Vhfti Oiilr, IKtltn.; Cm* * 0k9i . 'A; * 1 T *i t--rv ,V ' - Vieo* fab i .'.v'ji-Irtl ::'-4 kM fa fa- M*. JU! tot* U burs . r:' wn * inn n too00 J 140-2 >> . - w D30 HI son -i - fatal Cwiljad --2 15 (M l ` eso i Oipiliw fariaa lUflMk - fatTM : Lfa iso-tss - 2R III -4 *.. r"' 41 IU *. - 7J . iu J*r-- -r.-- ns- -m"- - - 1 ` (.43 ' S3 sat _j L24 L~t J23-^ in . HI 1 (77 .-n.**- 'iu -4 - (11 ., 0 v VO ... J * 9tipnfa| fattm iiuca- - 705- 1 -12 .tm-* : u> - -v . ' 1 SM ..- U rf... i fa*, tew** : --W: *' tin*, fa fart MWfd'W'F''*- " u *- .-U r>.*r-4j ' U9 $ fcmL * v 17* Y 0 41" 1 raz Ti fartW 44 us-:. i .MS i - ttfay Or|M in-in-. 31 141 It . ms ..Nt OtMr `.ffam faikrti '' - Ottir-1 UnpfaM-i m i Vfitttormt - X&m. 2QW. _ T ix-~e . ass Va-'-v tsr'^ in r rt-.aoo 9 42 ITS ; Ltt ,{ lafaria Diracs MMWg. 2M 19 on -t O.if'V 42 1J 11 143 i r fam* (MM . * CfetWory Sratan met Cafafnitw fattt " *' CkrtuH d Uwr sn . Sf.. - - ' 1531 J 1 * *219 : 47 " DifaejwJuid 1 thttoiftii ... WMi fafat krfVfcfa* ww - - . 7 in - MIS 231 ^7*1 I SO ^15 -: 1C2*- -j1 12* - 3 : 440 :i t : t'^SS. - oil ; i -3'' ; 440 -I T- ^ W II - *th.?`V r'-i '7J9 f _5mc4 ' ; H Otlw Cww 'OtaM U0W949 134 4.13 . (-32 40 123 - -2 0-33 : i v.-r . . -jj 'Ana - (U>ms^-L;tfwJr-Uaf-stKufi.w3f T4H 9. -- OWrtMtw V CiMk *m MkM Cauuc Anuf ^ twpleyfa* 17 NC ffartofa* 1* fai. fanfaK* Italy, 11(4-1173.1 . *4 j. * \\ Bkfa- /\ * ' fa d fatffc V . tafa. 'Jfa. ' S fa. " , An fa* m 10040 34 iuj v ` AH.ttttr* ' UHtt M . mt t 1S i face*! CMy urn Phtf>rK r*' 140-m ' '".V 6" -V *T PiSMthM ly>fai . 15W . ; - 72? . 4 UjC7 J ` llfa 1 3 ii!- 1 # ` ** *** : ' ' 193 T -- - : : M3 I - 44t * ' ikm % i,:. 1S4 - . 026 - 0 >J - IIMT v UnpiratBTSfsrOT 1 mio ... * . 1. ' 7. 044 - 3J9 1 0 -] ,`t lung. . 1(3 v- Vr. >* 7. 1J* -* -- ' -r^ > fa Ctfki ' - +m SLr * -ToaoL fa kmaC"T' 170-174 i.r* s `i * -- . . 3 12JT1 ii Brat "f1* ' 174 * * 3 ` faftitM 1 1H-IV7 . Uriwy Ortww - m-;i9 . >* , -3 _ 232 , B } UI 0_ j! * Brfa t fatrt Otfa , fat** ^`rr-' * IS'M' S?- IFF"- r'-Duw 1 Ihwfart - 110. 1934*1 ,'r .. 133- - 0 *A 0- V r iiftfpii... * - 200203; 20I4QS -' ^ 4 222. . 0 0 .* ! IfallTlH - ' 0f - > 2 ` Ml - -1 -- 4,11 i . Dbbtlis 24Q ' 2 1J1 0 ! , fiwri tf *' Cmfafay fan* * msi F -Ht-'-jjV " "ft. %`S." "4Utt .y CffaMii : 430431 " - is 1056. - 3 1250-1 - Cirtcn rt LW 571 w,.faWtfa. Chofaydfa, .* r ;*;'r - ; ' tMtmilit ' i ' 574S7S ` - 2 U? ' ' y. -T v 'ifrr >r ..rff . " '0 sit ; 94 ; Araifa Sfafa* 4 Vicrtm - < ' - .edJ*'*.'-** dOM9 ` ' jj L ; iur ''a ki Acddlrt* QOMW 13 t.44 1 *.! Sukirtt Et50{45t 2 ML B 0 ! . 'AN Dtto Cam-* ; mm ^ , fair 'x?*-:'."7 jpriiT.':ia ir`-tr ** --"t ``t~---- ~1- "-iirfir * -6 atm. 2 A * 'J, cen (rated In digestive system cancer, given the Urge number of deaths <31% ef aU cancer deaths). For each of the sites within the digestive system, observed numbers of deaths are greater than ex pected. Although, except for intestinal cancer, the observed num bers of deaths are small The PMR for liver cancer b rather high, but a definite conclusion is difficult wtth only six observed deaths. On the other hand, the PMRfor cirrhosis of the liver suggests a deficit in mortality from that cause. For white women, the PMR for total cancer appears high, as it did for white men, with cancer of the digestive system and, perhaps, cancer of the breast contributing a fair amount to the ex cess. Tht PMR* for individual sites within the digestive system are based upon small numbers but suggest an increase in Intestinal cancer. The PMR lor urinary cancer, though bated upon only 11 deaths, seems strikingly high and may be an Indication for further investigation. On the other hand, in contrast to the observation In white men. the PMR for respiratory cancer among white women Is very close to unity. Similar to the observation In white men, mor tality from cirrhosis of the liver seems to be in deficit but the corresponding observed number of deaths fc quite small Among both white male and female employees, diseases of the circulatory system account for a brge percentage of total deaths, in each case, observed numbers of deaths are dose to expected. There appears to be a somewhat different pattern among men and women for deaths due to accidents, poisonings, violence with the number of deaths somewhat low among men and high among women. There were 39 cancer deaths among nonwhite men, somewhat greater than expectation, although the numbers by site are too small for meaningful analysis. Mortality from cerebrovascular disease appeared high (PMR 2.111 but the Finding was based upon only 19 death*. Discussion The present study was designed with two objectives. The first was to determine whether or not any angiosarcoma deaths had 626 Mortality Among Employtea of FVC Fabricators/thiarte, Nichols, and Wong AP00006971 ut the .mortg utotory it each . There n and Wththe among newhat are-too oscular i based The fan iths had Ad Wong occurred among employees of the PVC fabricators under study. Since no angiosarcoma deaths were found among the employees studied, the first question has an unequivocal answer. A secondary objective was that of examining the distribution of deaths by cause among the employees under study. Implicit in that objective is the question of whether or not that distribution is, in some sense, unusual. There is no unequivocal answer to the latter question. Whether or not an observed distribution of causes of doth Is unusual clearly relates To the standard or comparison population as well as the analytic methodology.' On the bash of a proportionate mortality analysis, there appear to be excesses In total cancer mortality among both white men and white women in- the study, when compared to the distributions of deaths for the total United States specific for color and sex end adjusted for age. Excesses in cancer mortality appear concentrated In cancers of the digestive system and, in particular, in cancers of the intestine for both men and women. In addition, there is a suggestion that mortality bom cancer of the breast and urinary organs among white women employees is higher than that for the total UA There are, however, several reasons why Journal ef Occupational Madieine/Vol. 19, No. 9/September 1977 definitive interpretation b difficult. It has, for example, been suggested that a Proportionate Mortality Ratio based on an exter nal population may not be sufficiently discriminating in screening far potential hazards.* In addition, an analysis using PMRi fails to take account ol the absolute risk of dying In the population under study.* Further, a number of studies have suggested an overall favorable mortality for industrial working populations, even in those where well-defined hazards Increase' risk for a specific cause.* * factors such as these are meant to suggest del proportionate morality analysis must Ire interpreted cautiously' with the intention of . providing leads for further investigation. Results consistent with those of previously published studies would be of particular interest With no comparable working populations in the fabrication industry, potential contrasts may be found In studies of vinyl chloride workers. Monson, ef al. provided a proportionate mortality analysis of Iff deceased workers fall presumably white males) in two plants, one where vinyl chloride monomer is produced and one where it Is polymerized into polyvinyl chloride.* Result! of that study suggest a possible excess In total cancer mortality, primarily cancer of the 627 AP00006972 1 liver. However, there wu a suggestion that cancers of the lung tin entire US. specific for color and sex and adjusted for age by and brain also appeared with txetss frequency. The current study, while suggesting an excess in total cancer, particularly digestive cancer, does not clearly point to marked excesses for cancers of the liver, lung, and brain among white men, although the PMRs for these cancers are greater than one. The observed-to-expected PMR feportad by Mornon for vaxular Iwtoni Effecting the cen tra) nervous system, circulatory diseases, and external causes are similar to those reported hare. Tabershaw and Gaffey, in a study of workers engaged In the manufacture of vinyl chloride and hi polymers, conclude tint no specific cause of death was statistically significantly greater than expectations based upon Standardized Mortality Ratios ISMRsi using the U S. male papulation as the standard.* Ely other criteria, however, the authors conclude there may be an excess risk for mortality from digestive cancer, respiratory cancer, center ol other end unspecified sites, end lymphomas. At lower exposure levels, they suggest some excess for cancers of the buccal cavity and cancers of the Other and unspecified sites. The current study would seem to indicate that excesses of mor tality from cancer of the digestive system are not sex-specific and are not limited to liver cancer. The majority of the PMRs for cancer among both white men and white women ere in excess of unity. Sudi results must be interpreted with eaution but since they ap pear to be consistent with previously studied workers, they suggest the need for continued investigation. Summary Results of a study of 4,341 deaths occurring among current and former employees of 17 PVC fabricators during the period 19641973 are presented- The study was carried out to determine whether any angiosarcoma deaths had occurred among em ployees of these fabricators and to examine she distrfeution of deaths by cause. No angiosarcoma deaths were found among the stvidy population. Distributions by cause of death among whim male and white female employees were compared with those for means of Proportionate Mortality Ratios. There appears to be an important excess in total cancer mortality among bods white male and white female employees with digestive cancer, particularly that of the intestine, contributing to the excess. Among the women employees, cancers of the breast and urinary organs may also be in excess. No excesses were found for diseases of the cir culatory system. There were deficits in mortality from cirrhosis of the liver among both male and female employees and a deficit in accidents, poisonings, and violence among men. The use of the Proportionate Mortality Ratio based on an external standard requires caution in interpreting these results, but the need for fur ther investigations is indicated. Thb itutiy twu iponiorvd by the foBouring organisations; American Can Company, 0, F. Goodrich Company. Diamond Shamrock Corporation, ffmtooa Tire and Rubber Company, lohrH MirvAc, Motor Vehicle Manufacturers Association, Sttuft** Chemical Company, Union Cifbde Corporation. UntayaL Incmpwrad References I.Selfkoft U ad Hammond EC (Eds.): Tpalc*ty of vlnyt chloride --polyvinyl chloride- Ann H.Y. Acid Sc/ 344:1975. 2. Manual ol Che International Classification of Disease* Adapted for Use In the United States- Eighth Revision. Washington, D.C. U5- Govt. Printing Officer 1967, VcJ. 1. 1 National Center For Health Statistics: Vital Statistics of the United "States. I960 ''Volume'll * Mortality. Part A- Washington, D C - Ui Covt. Printing Office 1972. pp. 140*205. 4. Chlam L: Problem* of Study design and Interpretation of industrial mortality experience, JOM 1i:169-170, 197S. 5. Redmond CK and 9re*rm PP: Comparison of methods for assessing oc cupational hazards. JOM 17:313*317, 1173. 6. Mortton XR. Petert |M. and Johnson MNi froporffonal mortality among vtnyhchloride workers, Lwcel 2:397*390, 1974. 7. Lloyd JW and Cfccco A: Long tm mortality study <* Steelworkers: 1. Methodology./OV 11:299*310. 1969. A fttdmend CK. Ooceo A. Lloyd |W, and Hush HW: Long term mortality study of steelworkers: IV. Mortality from malignant neoplasm* among coke wen workers. fOM 14:021-02% 1972. 9. Tabershaw IE and Gaffey WX: Mortality study of worker* In the manufacture of vinyl chloride and Its polymers. K)M 16:509-510, 1974. & V i* ii < V I F! 'F t > S r I 7 t c t r f tiU * cr : tr c T r K i Si 628 Morality Among Employees of PVC Fabriutors/Chiazze, Nichols, and Wong k t ,.L_ .. AP00006973