Document XO5xZvKq1LrYpNNwpONVdM0B4

Lung Cancer and the Petroleum Industry in Louisiana Marise S. Cottlieb. M.D. Death certificates from the period 7 9 6 0 to 7975 for Louisiana were surveyed for lung cancer deaths and nom cancer deaths among people employed in petroleum miningand reiining to determine iithere were specific occupations within this industry associated with a higher risk of lung cancer. Workers employed as welders, operators, boilermakers, and painters and oilfield workers had the greatest risks. Oil field miners born outside Louisiana had a higher risk than native-born miners. Occupation as listed on death certificates provides a rapid means of identifying those with high risk, as a large part of the population can be rapidly screened, covering employees in many in dustries. A study of geographic patterns of cancer in the United States revealed that parishes in Louisiana have some of the highest age-adjusted lung cancer mortalitv rates for 1950 to 1969.' IMoreover. these parishes are contiguous in certain areas, particularly along the Gulf Coast, the Mississippi River, and urban areas. To determine tactors intluencing lung cancer mortality rates in Louisiana. 19 parishes were selected for a case-control death certificate studv. National correlation studies suggest that occupational exposures in the petroleum, paper, and chemical industries mav account for some of the excess in lung cancer mortality rates for certain U.S. counties.' The petroleum industry is a major industry in Louisiana, employing many of the people currently working in the petroleum industry in the U 5.An increased relative risk for lung cancer was noted primarily in men over 62 years of age in oil production and retinen/ industries. and in 4rrociate Protesror of .Medicine 3nd Epidernioloqv Tulane L n i b ~ r ~ St vchool ot Medicine and P d i c Health and Tropical Medicine i 4 3 0 Tuldne 4ve Yew Orleans LA :011? 384 residents of towns where the petroleum industry was major emplover.' Other industries with occupations associated with lung cancer included shipbuildb machinen manutacturing, petrochemicals, transpa tion, and construction. In cancer mortality stud,e employees o i oil refineries, no significant asociatim occupation with cancer risk have been identified, desF. the availability of work histories. Since Louisiana has many oil refineries, a popuiak based mortality study allows the identificdtion a greater number of exposed individuals, across in&,& factories, but with occupations in common. Theriault 3 Coulet.' in comparing the cancer mortality of oil refin workers to the Quebec population, found lung card less frequent than expected, an unusual excess of k. cancer in young people, and an elevated SMR for cam of the digestive system plus an elevated number oi ded: due to non-neoplastic diseases of the digestive sysn Hanis, Stavraky and Fowler,' however, found more !ha! three-fold risk ot esophageal and stomach cancer, 2 twice the risk o i lung cancer in exposed compared to PS exposed petroleum workers. In the exposed grccio. creasing risks for both disease categories occurred I increasing duration or employment. An examination ot deaths with a recorded h i ~ : ~ emplovment in the petroleum industry is pesentei identify associations with the elevated risk from c a n e the lung in this industry and occupation. Methods Parishes included in the Lousiana studv were: ACJC Allen, Ascension, Calcasieu, Concordia, lberville, lack+ Morehouse, Plaquemines. St. Bernard, St. Charles. lames, St. John,St. ,Martin, Tensas, Terrebonne, Wash ton, Webster. and West Feliciana. These parishes 9 selected because ot elevated lung cancer death f3 among white males for the years 1950 to 1969 or becj of their concentration of petroleum, chemical, and pa' manutacturing industries, or both. Lung cancer dcd c b males ~ r dmrales TarJ -Table 1. Reporting of Occupation on Oeath Certificates for Cancer Deaths and Non-Cancer Deaths Employed in the Petroleum Industry for White and Black Males. Petroleum Industry (Codes 049. 377) Cases Occupation Reported Not Reporled 181 12 (6%) 70 200 Controls Occupatlon Reported Not Reported 153 12 (7%) 50 170 I adadifid by ICDA number from a data tape of all -deaths from 1960 to 1975 compiled by the Loui- m i o n of Vital Statistics Notation of cancer a p anywhere on the death certificate is coded, and -able as the underlying cause An equal number ot rrr-er deaths were selected as controls and yrhtd to the lung cancer cases by sex, race, year of .udL pansh of residence at death, and age of death ( t rg v t u s L The first control, meeting the criteria, in se -.LKCoc)the tape was selected &a& certificate for each subject was abstracted @ obbh information on other contributing causes of w a c u p a t i o n and industry Occupation and industry W coded by the three-digit classifications of the U 5 Bureau Analysis for relative risk with 95% con- hdervals is by the modification of Rothman- `ehtrWithin the petroleum industry, occupational were compared for cases and controls, and for I/ *rxdcath. Qm&B 1970 census for 19 parishes included 346,041 *A total of 2,803 cases of lung cancer among males 'f acertained for the study period For this group, Were white males and 642 were black * w f i o n was sufficient to classify the decedent's &5tn/ of employment into one of 22 industrial wb for 87% of white males and 60% of black 4 4 b~ e was no significant difference between the :- tB rrcbkqe of controls by reported industry for either **t m P Occupation could be coded trorn death cer- '[ infomation for 92% white males and 92% of W e s . Occupation was reported for a greater number of cases than controls for both whites and blacks. However, for the petroleum industry, there was no significant difference in reporting of occupation for cases and controls (Table 1).Since there were only 1 2 black males in the study population who were employed in the petroleum industry, the following results are presented for black and white males combined. A total of 200 cases were employed in the petroleum industry, 125 in mining and 75 in refining. There were 170 controls employed in the petroleum industry, 112 in min- ing and 58 in refining. For purposes of analysis the mining and refining data were combined under the heading of "petroleum industry" as many occupations were similar in both categories, and it was assumed that exposure to hydrocarbons was the major factor in both industrial sub categories. The distribution o i occupations for males employed in the petroleum industry is given in Table 2. The odds ratim for cancer for employment in the petroleum industry, 1.19, does not include 1.0 in the 95% confidence limits. Moreover, several occupational categories within the petroleum industry are noted to demonstrate greater risks tor lung cancer mortality. For workers and oilfield workers, welders, operators, boilermakers, and painters, the odds rstio is 2.33. This increase is mainly in those over age 60 at death, as noted in Table 3, where the data are < >presented for two age-at-death groups, 60 years and 60 years. A larger proportion of controls than cases died at less than 60 years of age, particularly in the managerial categories. No increase in chronic obstructive pulmonary disease was reported in deceased petroleum workers compared to non-petroleum workers. This disease was recorded for f t I Pumping and refining Wators i hhakers zrs ial, professional. sales 28 13 2 33 (1 42-3 85) I: ,! i Upational Mediclne/Vol 22, No 6/June 1980 385 I \ ! ! j j I ~ ! ! !i ! 1! 1! 1I if I i 'I I! I 4 j i !j ! i! Ij II I i ,! j! I I Occupation Workers, oilfield workers 'Welder . "1 Cases 6 5 Controls OR Cases 5 1 36 (024 22 48) 20 1 1 a9 10 48.7 37) 3 Controls 1 f Cooks chefs stewards Managerial professional sales Skilled construction Skilled pumping and refining Transporlafion guards Total petroleum .vOrkers Total lung cancer 12 17 34 23 18 29 26 28 46 87 95 1005 1137 I1 -Table 4. Chronic Obstructive Pulmonary Disease (COPD) in Petroleum Mining and Refining Workers and Matched Controls. Occupational Group Petroleum- related Non- petroleum- related Relative odds (95% confidence interval) Cause of Death COPO Non-COPD No. % No. 1 1 6.5 13 8 0 159 155 0.82 0 58-1 17 ten and fibrosis in one of the 170 petroleurn wc:kers dv- ing from causes other than cancer (6 5%). Twelve cases of chronic obstructive lung disease and one case of fibrosis were recorded for the 168 non-cancer deaths in subjects not working in the petroleum industry matched to the petroleum workers dying from lung cancer (8%)(Table 4). The location of the lung cancer is indicated in 27% of the cases. Particulate matter is preferentially expected in the right lung. Among the 200 lung cancer deaths in petroleum workers, the right lung was indicated for 32 cases and the left lung was indicated for 22 cases. The difference was noted largely in those categorized to petroleum mining (Table 5). However, interpretation is dif- ficult due to the large number with unspecified location. The mean age of death of the cases was 60.5 years. A large number (58%)of petroleum worker controls died at 59 years of age or younger, and more than half of these deaths were due to trauma or myocardial intarction. The distribution of cases and controls by their ages in 1945 (around the time of the offshore oil boom) is given in Table 6. The controls were generally younger than the cases; 59% of controls were 34 or younger compared to 35% of cases. This again reflects premature death from 132 (092 190) 3 20 25 25 0 74 26 -.:. , lo 243 (1 01, 5- - :, 0 28 (023 0 35) 8 8 113 1798 48 (049.1+, -. -7 71 $$.--*.,. ! .c 1666 t->-- 1. ?< - other causes in the controls A chi-square anal&& distribution of cases and controls born in LOUS * mout-of-state reveals an excess of cases in tb bpetroleum mining occupations (welders and % workers) born out-of-state (Table 71 [RO 2 27 fidence interval 0 58, 8 8311 This associatlon pear for refining workers Discussion The elevated risk of lung cancer petroleum workers in these selected Lou1 attributable largely to several occup we!ders, oilfield workers, operators, painters An excess in cases among boile &painters was observed for the entire data set ( a q a a dustry categories) as well as for the petroleum alone However, the excess among cases rrs welders, which IS apparent in the petroleum-,*i not observed across all industry categories It b that different factors are operating in the e t i o l w d b cancer for these three occupational groups The and worker categories are specific to the dustry The association between chronic obstruct nary disease (COPO) and petroleum-related -co a&was also examined This can be considered a -# the relative amount of cigarette smoking by this industry To measure this association, the controls (non-cancer) of the cases working in I r petroleum-related industry were compared with Jf l ~ trots who were reported to have worked in the nduR The resulting percentage of COPD deaths for peaoOrrr i related occupations, and non-petroleum-related tions was 6.5'and 8.0, respectively (Table 4). This the accuracy and similarity of diagnostic reportirr)m)r -Table 5. Laterality of Lung Cancer in Petroleum Mining and Refining Workers and Matched Non-Petroleum Workers. Occupations Petroleum mining Petroleum refining Non-petroleum-related Laterality Specified Right Left No. % No. 20 63 12 12 55 10 25 54 21 % 38 45 46 uMm Ilr 9y9 124 * t 386 Lung Cancer and the PetroleumIndust- -* able 6. Petroleum industry Cohort Age in 1945. ; 0-19 i 20.34 ! 35+ win 1945 not available Tool Cases No. H 10 5 59 30 130 65 Controls No. x 21 12 79 47 70 41 10 200 170 groups, and the security that all cases of lung cancer mlikely identified and reported, or one might have ex- to have identified more non-specific lung disease. Iht similarity in the proportion of petroleum-related ;-Is with COPD compared to that from nonrcrdeum-related controls suggests that cigarette smok- q does not differ in the two groups, and that the higher *& or lung cancer associated with the petroleum in- tny is not likely to be related to cigarette smoking b e . The reported rate of 6% COPD is lower than that bnd in a similar comparison of workers related to the Wmiiding industry.' T)r laterality of lung cancer was also investigated -occupationalgroups, since particulate substances and to be trapped preferentially in the right lung due to bconfiguration of the right bronchus. To measure this *w a t i o n , the cases not working in the petroleum inwho were matched to the controls working in these =cupations were compared with cases working in m r n industry occupations. The resulting proportion *.f noht lung cancer in the petroleum industry occupaWas not increased significantly above that of lung UYncases in the non-petroleum industry occupations. b,information on laterality was specified in only J y Of L ! iase;. mean age at death for cases was several years *than that for controls. Similarly, the median age of for casesbzwas substantially greater than that for ~ o k c"onsidering that cases and controls in the -1 data set were age-matched t two years. (For all `*rdustnes combined the median age at death was 62.8 for and 61.4 for controls.) These findings may be ex-by the fact that many of the deaths for controls in moleurn industry were accidental and occurred in - W n g men, who might have become cases, if they u m k d . This indicates that risk of lung cancer for * may be underestimated in this study. A revised ratio was estimated after excluding accidental, -atiC or violent deaths, chronic obstructive pulmonary disease, and those whose age was less than 40 years at time of death from the control group. It was 1.29 (1. l l to 1.50) for the petroleum industry. For the high-risk occupation group in this industry, the corrected odds ratio is 3.03 (1.45 to 6.34). a further elevation. This reinforces the significance of the risk of these occupations. The ages of cases and controls relative to a reference date, 1945, were examined to see whether differences in the ages of the two cohorts might result in differing temporal exposures for the two groups. More controls were under 35 years of age and more cases were 35 or over. The older cases probably reflect J longer period of exposure to the industry. The observation that petroleum mining cases were more frequently born out-of-state than controls is p r o b ably related to migration patterns involved with employment in the industry. Those mining workers who relocate frequently at new mining sites are probably long-term employees in the industry and therefore long-term exposure, high-risk employees. The odds ratio for these workers is elevated, but due to the small sample size, was not significant. Retining workers, on the other hand, were not more likely to be born out-or-state. The observation that lung cancer was recorded more frequently for the right lung than the left lung particularly among the miners is compatible with the idea that airborne particulate substances contribute to the etiology of lung cancer. Whether or not differences in cigarette smoking pat-. terns associated with social class and occupation is the common denominator in the differences between cancer deaths and non-cancer deaths cannot be directly evaluated from this study. Indirectly, however, the high median age at death in cases and the similarity in percent reported COPD for cancer and non-cancer deaths would tend to require mc:e thzn differences in tcbaccc?smoking patterns as an explanation Conclusion National correlation studies have suggested an associa- tion between employment in the petroleum industry and lung cancer mortality. This death certificate study has demonstrated an elevated risk of lung cancer mortality -(odds ratio 1.19) for workers emplbyed in the petroleum industry in 19 selected Louisiana parishes. In- dividuals with several specific occupations within the petroleum industry (welders, operators, boilermakers, painters, and oilfield workers) appear to be a greatest risk of lung cancer mortality, RO 2.33 (1.42 to 3.85). The petroleum industry has been an important industry in I ... i 3- -! Table 7. Distribution of Petroleum Workers by State of Birth Louisiana and Other. Pf ladustry Occupational Risk Birthplace Louisiana Outside Lousiana Cases Controls Cases Odds Ratio Controls Mining All a2 61 44 30 odds ratio Mining High 24 16 17 5 2 27 [(058.8 8311 All 51 39 23 18 High 20 a 10 3 +of Occupational Medicine/Vol. 22, No. 6/June 1980 ... 387 Louisiana for the past 50 years and may explain part of the excess in reported lung cancer mortality rates. The use of death certificates representing a large population base whose employees are a t an increasedrisk of cancer is an alternative to studying the work histories of employees of individual companies. The large popula- tion base which enables surveillance of many death certificates allows the identification of workers from several companies and a broader identification of those exposed. Only for those individuals with a substantial period of employment is the industry likely to be recorded on the death certificate. This would tend to eliminate casual employees and allow the inclusion into the study of employees who achieved a long period of employment. This is true for cancer and non-cancer deaths. Specific job titles were recorded with a high frequency on the death certificate. Although the inherent weakness of death certificate information is well-known, it appears to be a valid screening tool for detecting industrial and occupational associations with lung cancer. Thor work wd5 supported under NCI Contract N O 61058. and Department of Health dnd Human Resources References *:1 MajOn T I and McKav FW U 5 Cancer Mortality bl? &1950-1969 Department 01 Health. Education and Weifam. (YIH) 74-615 Washington D c 1978 *s 2 Blot W j and Fraumeni I F l r Geographic patternr of Industrial correlations Am / E p r d e m d 103 539-550, , 9 7 5 4 b%3 Cottlieb MS. Pickle L. Blot W l and Fraumeni J FI, in Louisiana Death certificate analvsis / Vat/ 631137.1137 1979 -It 4 Theriault C and Coulet L A mortality study of workers / Occup Med 21 367-370. 1979 4 j Hanis UM Stavraky KM and Fowler IL Cancer retlnery workers / Occup M e d 21 167-183 19T9 %et 6 I;5 Census of Population Alphabetical Index of I Occupations Washington D C U S Government Pri 1971 7 Rothman-Boice Modifications of Miettinen 0s E ... estimation in case reterence studies Am / pidemlo/ -1 1976 tt, 8 Gottlieb MS and Stedman RB Lung Cancer in Shl Related Industries in Louisiana South Med / 72 1 0 9 9 --a1t1 ~ , y n I .! Aesculapian Authority Paterson defined medical authority as consisting ot three types: sapiential. moral, and charismatic, combined in a particular manner. He called this "Aesculapian authority." By sapiential authority, Paterson means the right to be heard that is derived from knowledge or expertness. Such authority resides in the person and not in any position that he may occupy. A person with this kind of authority may advise, inform, instruct, and direct, but not order. The second ingredient ot Aesculapian authority is moral authority, the right to control and direct that is derived trom the rightness and goodness according to the ethos of the enterprise. The moral authority of doctors, which is expressed in the Hippocratic oath, stems from their doing what is expected or them as doctors and their concern with the good ot' the patient. The third ingredient in Aesculapian authoritv is Charismatic authority, the right to control and direct that is derived trom Cod-given grace. This element in Aesculapian authority reflects the original unity of religion and medicine that still exists in manv parts of the woild. - From `Cod and the Doctor' Sv Humphrev Osmod. in The \ew England lOUrCdl o i .Medrcme March 6. 1980 i