Document 3QpOX0rbEna3j02ka1OK5Rq9n
AMERICAN
PublicJOURNAL or Health reprint Asbestos Disease in Family Contacts of Shipyard Workers
Kaye H. Kilburn, MD, Ruth Lius, MD, Henry A. Anderson. MD, C. Thomas Boylen. MD. Hans E. Einstein, MD, Sue-J. S. Johnson, MD. and Raphael Warshaw, BA
Abstract: Radiologic signs of pulmonary asbestos disease were found in 11.3 per cent of 274 wives of shipyard workers who were 20 or more years from initial hiring-on in shipyards in Los Angeles County. Asbestosis was also found in 7.6 per cent of 79 sons and 2.1 per cent of 140 daughters of these workers. The wives, sons, and
daughters were without occupational exposure. Comparable radio graphic signs were not found in comparison groups. It is probable that asbestos exposure in the household places these family mem bers at nsk for mesothelioma and lung cancer. {Am J public Health 1985;75:615-617.)
Introduction
Health risks1'2 are associated with even brief proximity to airborne asbestos fibers3 in many different work places. The risk associated with less direct exposure, although originally described by Wagner in I960* and later by Newhouse and Thompson in 1965.' has received little attention. In one study, family contacts of asbestos insulation produc tion workers showed a 35 per cent overall prevalence of radiographic abnormalities characteristic of asbestosis and resulting from secondary exposures in their homes.*
Shipyards have been the site of widespread exposure to asbestos for at least 3.5 million workers in various trades, and radiographically detectable asbestosis has been reported in several groups of such workers.In a recent study of 286 current and retired ship repair workers, most of whom were in "bystander" trades not working directly with asbestos, 86 per cent had asbestosis, and lung cancer was detected in five.10 The nsks for asbestos disease have not been assessed previously in family contacts of bystander workers.
This report concerns 852 subjects who were studied in 1981. and includes male and female shipyard workers and their wives, daughters, and sons. The objective was to determine the prevalence of asbestosis. i.e.. diffuse pulmo nary fibrosis and/or pleural fibrosis including calcification as seen by chest radiographs, in household exposed wives and children of shipyard workers, and to compare such preva lences to those in populations not so exposed.
Methods
The population studied consisted of 1.017 workers and their wives, sons, and daughters recruited from the Long Beach. Wilmington, and San Pedro areas of Los Angeles County by a public media campaign. Each respondent was screened briefly by a telephone interviewer to determine if the worker was 20 years of more from initial shipyard employment, i.e.. first exposure to asbestos. Appointments were made for examinations during May 1981.
Address repnni requests (o Kaye H. Kilburn. MD. Professor of Medi cine. ind Chief. Pulmonary Disease Section. Department of Medicine. University of Southern California School of Medicine. Bviow-USC Occupa tional Health Center. 2025 Zonal Avenue. Los Angeles. CA 90033. Authors Boylen. Einuctn. Johnson and Warshaw are also wuh the Bartow-USC Occupational Health Center: Dr. Litis is wuh the Environmental Sciences Laboratory. Mt. Sinai School of Medicine. CUNY. New York; Dr. Anderson is wtth the Wisconsin State Board of Health. Environmental Epidemiology. Madison. This paper, submitted to the Journal Apoi 26. 1964. was revised and accepted for publication January 3. 1965.
C 1965 American Journal of Public Health 009-0036>15 $1.50
AJPH Juno 1965. VoJ. 7S. No. 6
After informed consent was obtained, trained interview ers obtained information about occupational exposure and working conditions, pulmonary and cardiac diseases, respi ratory symptoms, particularly shortness of breath, cough, sputum, and wheezing, and knowledge and attitudes about asbestos disease. The occupational questionnaire was based on that used in a prior study of family contacts of asbestos workers* and in the studies for the effects of polybrominated biphenyls in the State of Michigan." The respiratory disease questionnaire included the Medical Research Council chron ic bronchitis questions with additions concerning asthma and the degree of breathlessness as recommended in the epide miology standardization project.'2
From 1.017 subjects studied. 13 were excluded as distant relatives who were outside the study categories and 13 subjects had incomplete data, usually having refused chest x-rays. There were 76 subjects whose asbestos expo sure was at work sites other than shipyards. Thirty-nine sons and daughters were excluded because their fathers were less than 20 years from initial occupational exposure to asbestos. An additional 24 shipyard workers, both men and women, also were less than 20 years from initial exposure to asbes tos.
The 485 women analyzed were either female shipyard workers, or wives or daughters of workers; 24 per cent were employed but none of the wives or daughters had worked with asbestos (Table 1). Comparisons were made with two other groups of adult women"13 (Table 1) who had been studied using chest radiographs and questionnaires similar to those used in this study. The 79 sons of shipyard workers were compared to 673 men (mean age 50 r 17) from the Long Beach census tract13 and 594 men (mean age 43 - 14) from the Michigan sample."
Posteroanterior and lateral chest radiograms (14 x 17 inch) were obtained in all subjects at standard six foot distance using conventional techniques. Chest radiograms were screened by a physician and repeated if they appeared technically unsatisfactory for evaluation of pneumoconiosis by ILO (International Labour Organization) criteria. There after. three experienced readers with at least "8" reader qualifications for reading pneumoconiosis (as established by the American College of Radiology) independently read the posteroanterior radiograms of ail three groups for presence and profusion of irregular opacities and presence and extent of pleural abnormalities (diffuse thickening, plaques, and calcification). They used the criteria of the 1980 revision of the ILO classification for pneumoconiosis14 which grades the profusion of opacities from absent (grade 0) to few (grade 1). to moderate (grade 2). and numerous (grade 3). All study and control x-rays had identification covered and were intermixed. The x-rays were graded from 0/0 to 3/3 by
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KILBURN, ET AL
TABU 1--Compoisons of Three Groups of Volunteer Women
Demographics
Par Cam by Age ia-34 35-54 55+ ages missing
Per Cent by Race White Black Other
% Employee % Exposed to asoestos at work % PessiPiy exposed to asoestos
at home
Women in This Study
(N:485) 22 32 45 1
66 13
1 24
0
too
Reference Group 1*
(N:674) 25 22 42 11
99 0 t
unknown 3
6
Reference Group 2**
(N:583) 43 35 21 1
93 6 1 54 5
16
*Cn*us tract nouaa to nouaa survey recrukmern. Long Baacn. CA. 1975-197S: ?5%
of troaa invitee were exemmee M3) ''SCautwa nnaom tvrcm, recruited Or gnone. hfcemgan. iS7S: *3% of thcee vwtee
ere auffmao MM-
arithmetic consensus of the three gradings. To be considered positive, two readings had to indicate the presence of asbestosis grade i/0, or definite pleural abnormalities. Read ings which differed by two or more grades of profusion, for example I/O to 1/2 or 2/1. were reviewed by the three readers as a panel until they reached a consensus. For the following analysis irregular opacities with a profusion of I/O or greater were considered as positive for asbestosis as recommended by ILO criteria. Similarly, pleural findings were counted as positive if any combination of pleural thickening, plaques, and calcification were consistent with asbestos disease. The term asbestosis. when used in this report, is synonymous with radiologic signs of this condition.
TABLE 2-Pravalence of Aabeetoeis of Lung* and/or Pleura for Ship. yard Worker* and Family Contacts and in Long Beach and Michigan Comparison Populations
Groups
Per Cent with n Asbestosis
Male Shipyard Workers Female Shipyard Workers Wives of Shipyard Workers Sons of Shipyard Workers Daughters of Shipyard Workers Companson Population
Long Beach Census Tract Men Long Beach Census Tract Women Michigan Sample Men Michigan Sample Women
288 71
274 79
140
673 674 S94 563
642 21.1 11 3
76 21
37 06 0.5 0.0
Decade of birth was used as an approximation of years from initial exposure to asbestos for creating four groups so that asbestosis prevalence could be compared in shipyard workers and their wives. This was done because exact dates of first asbestos contact were unknown or first contact was outside of shipyards.
Results
The prevalence of asbestosis in the shipyard workers and their wives and children is shown in Table 2: a detailed breakdown of diagnostic criteria appears in Table 3. The male workers had engaged in all skilled shipyard trades. Many had begun as laborers and no trade predominated. Their mean age was 61 ( 10.8); 8! per cent had a history of cigarette smoking, although at the time of the study, only 25 per cent continued to smoke. Asbestosis was present in 185 (64.2 per cent) of the male shipyard workers.
TABLE 3 Radiologic Sign* of Aabaeteeie )n OHterem Group* of indhriduel*
Profusion of Irregular Ooaooas
GfouOi*easo
0/0 0/1 VO VI >\;1
Maw Shipyard Workara (N - 286)
iOomy
99 72 S3 50
FT - PC
26 42
FT - PC + O
27 29
Negative
73 X
Female Shtpyard Workers (N 71) 10 only
$0 14
4
1
PT - PC
53
PT PC * 10 Negative
J0 45 11
Wives (N - 274)
Oonfy
221 34 16
3
PT PC PT PC * 10
S7 0 21
Negative
216 27
Sons <N 79) Oonfy
69 7 2
1
PT + PC
21
PT * PC + O Negative
20 27 6
Oeugmera (N - 140)
Oonty
132 7 t 0
PT + PC PT + PC * O Negative
20 130 7
0
0
14 10
2 1
0 0
0 0
0 0
NOTES: C - regular eeaeeee n FT PC orarti aeaewng amor <.nr.Tfi.rarr. uneertnae nurer* warn coueee lan.'ipmrg omarea
Total t%>
51 (17 7) 68 (23.6) 66 (22 9) 103(35 8)
5 (7 0) 6(11 3) 2 (2.8) 56 (76 9)
16 (5 8) 12 (4 4)
3 (1 1) 243 (66 7)
3 (3 6) 3 (3.8) 3 (2.5) 73 (92.4)
t (0.7) 2 (1 4)
137(97 9)
610 AJPH Juno 1965. Voi '5 No 6
All of the women shipyard workers were wives of male shipyard workers; two had been insulators and one had been a welder: 32 were present or former cigarette smokers; 21.1 per cent had asbestosis.
Mean age of 274 wives was 58 {- 9.5); asbestosis was found in 11.3 per cent and was equally frequent in nonsmok ers. ex-smokers, and current smokers. Three wives who were cigarette smokers had lung masses detected by chest radiograph. Two of these were cancers and one was sarcoid osis.
Six of 79 sons (mean age 29.5 s 8.3) had asbestosis, as compared to three of the 140 daughters (mean age 32.3 s 10.3).
Analysis of workers by decade of birth showed a strong relationship between decade of birth and asbestosis preva lence in shipward workers; in the wives of workers, the relationship is less striking but remains suggestive (Table 4).
As shown in Table 2, the prevalence of radiologic signs of asbestosis were far higher in the wives, sons, and daugh ters of shipyard workers than in the two comparison groups studied.
Discussion
Most of the shipyard workers studied did not work directly with asbestos, but were exposed to airborne asbes tos during application and ripout of insulation by pipe coverers and insulators. Finding asbestosis signs in 11.3 per cent of their wives is fresh evidence of the pervasiveness of asbestos as an occupational hazard carried home by work ers. Those wives bom in the decade 1900-10 had the highest proportion of asbestos signs, two-thirds as high as the 48 per cent in wives of Paterson, New Jersey insulation factory workers studied by Anderson, et al.4-,s
Sons without occupational exposure to asbestos had a 7.6 per cent prevalence which is in keeping with their youth. If exposure of the sons began in infancy, they may continue to develop asbestos signs throughout their lifetimes, and the prevalence will rise as they grow older. Only 2.1 per cent of daughters had asbestos signs. A similar sex difference was found at Paterson.14 Reasons for the difference are un known. but may reflect greater difficulty in recognizing irregular opacities through the breast shadows on chest radiographs.
Although shipyard workers appear to have lower expo sures to asbestos compared to those making asbestos insula tion products.7-9 the gradient of asbestos signs with earlier decades of birth suggests that the time lapsed from first exposure may be a more important determinant than is the average dose.
TABU Comparison of the Prevaianca of Aabaatosis in Worttare end Whrea. fry Oocado of SJrtn
Maw Shipyard Workers
Whrea*
Oecada of Birth .
N
% Poamva
N % Poaibva
1900-10
37 865
22 31 8
1911-20 117 70.1
90 12.2
1921-00
93 01.7 102
78
1901-40
39 30.8
48 10.2
tncSjasi owfiree eon were nfltsrewnd "breaker were notuasnenanmeiaae
AJPH Juno 1965. Vol. 75. No. 6
ASBESTOS IN SHIPYARD WORKERS' FAMILIES
All studies, particularly those involving human volun teers. may be biased. It is possible that the shipyard workers and family members who volunteered for this study were more aware of the dangers of asbestos exposure and that a higher proportion had been previously diagnosed with asbes tosis than a random sample offamilies of present and former shipyard workers. However, we collected data during this study about health awareness and previously recognized respiratory diseases and symptoms. Analysis of these data (to be reported later) did not bear out this possibility.
Although data on risks to family contacts of shipyard workers are still incomplete, five mesotheliomas have been recognized in family members of asbestos insulation manu facturing workers in Paterson.* We believe that, the feasibil ity and benefits of undertaking surveillance foe cancer in the families of workers exposed to asbestos should be consid ered. particularly for individuals who continue to smoke cigarettes or who have smoked for many years in the past.
'Anderson HA: Unpublished data.
REFERENCES 1. Selikoff IJ.ChurgJ (eds>: Biological effects of asbestos. Aon NY AeadSci
1965; 1)2:1-766. 2. Selikoff IJ. Hammond EC fedsr Multiple nsk factors in environmental
cancer. In: Fraumem JF Jr ted): Persons ax High Risk for Cancer. New York: Academic Press. 1978. 3. Seidman H. Selikoff !J. Hammond EC: Short-term asbestos work expo sure and long-term observation. Ann NY Acad Set (979:3X1:61-49. 4. Wagner JC. Sleggs CA. Marehand P: Diffuse pleural mesothelioma and asbestos exposure in the North Western Cape province. Br J Ind Med I960: 17:260-271. 3. Newhouse ML. Thompson H: Mesothelioma of pleura and peritoneum following exposure to asbestos m the London area. Br i lad Med 1965: 22:261-269. 6. Anderson HA. Lilis R. Daum SM. Fischbem AS. Selikoff U: Household contact asbestos neoplastic nsk. Ann NY Acad So 1976; 271:311-32). 7. Selikoff U. Lilis R. Nicholson WJ: Asbestos disease in United States shipyards. Ann NY Acad So 1979: 330:295-5)1. 8. Polakoff PL. Horn BR. Scherer OR: Prevalence of radiographic abnor malities among northern California shipyard workers. Ann NY Acad Set 1979; 3)0:333-339. 9. Felton IS: Radiographic search for asbestos-reined disease in a naval shipyard. Ann NY Acad Sci 1979: 330:341-352. 10. Selikoff U. Nicholson WJ. Lilis R: Radiological evidence of asbestos disease among ship repair workers. Am J lod Med 1900: 1.9-22. 11. Selikoff U. Anderson HA: A survey of the general population of Michigan for health effects of polybrominaxed biphenyl exposure, in: Report to the Michigan Department of Public Health. September 30.1979. Environmen tal Science Laboratory. Mt. Sinai School of Medicine. 12. Ferns BG Jr Epidemiology staodardizaiioo project. U: recommended respiratory disease questionnaires for use with adults and children m epidemiological research. Am Rev Respir Dis 1978: I IS (No 6 Part 2) 35. 13. Detels R. Sayre JW. Couison AH- Rokaw SN, Massey FJ Jr. Tashkrn DP. Wu Mei-Miau: The UCLA population studies of chronic obstructive respiratory disease: IV. respiratory effect of long-term exposure to photochemical oxidants, nitrogen, and sulfates oo current and never smokers. Am Rev Respir Dis 1981; 124:673-680. 14. International Labour Office: International classification of radiographs of pneumoconiosis 1980. Occupational Safety and Health Senes 22. Geneva: 1LO. 1900. 15. Anderson HA. UJis R. Daum SM. Selikoff U: Asbestosis among house hold cootacts of asbestos factory workers. Ann NY Acad Set 1979: 330:317-399.
ACKNOWLEDGMENTS This research supported by a pant from the American Lung Assoaauon of Los Angeles County. This study was presented m part to the American Thoracic Society meeting. May 9. 1903.
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