I

~ Asbestos Diseases and Pulmonary Symptoms and Signs in Shipyard Workers and Their Families in Los Angeles Kaye H. Kilburn, MD; Raphael Warshaw; John C. Thornton, PhD

••

..

~

4 ~

t

• F.mlll•• of 338 m.l•• nd " f.m.l. .hlpyard work.r. (SYW), Including 280 wlVII, 144 d.ughter., .nd ., .on., were .x.mln.d tor dl •••••• re.ultlng from •• be.to•. ",. workers were Inltl.lly .xpo•• d to •• b••to. It I•••t 20 y••,. prior to the Itudy dlt•. R.dlogr.phlc .Ign. of IIb••to.l. (u.lng .t.nd.rd crlt.rl. Int.rn.tlon.1 Labor Offlc. 1180) were found In 14% of 288 m.le SYW .nd 21% of 71 t.m.le SYW. Attar excluding tho .. with .ny occupatlon.1 .xpo.ure to •• be.to., llbe.to.l. prev.I.nca was 11% In wive., 1% In .on., .nd 2% In d.ughter•. A.b••to. dl..... prev.l.nc. In WOrkl,. and In wive. Incre•••d with the numb.r of Yllrl from Inltl.1 opolure. Mal. SYW who h.d .moked had alrw.y obstruction without volume 10••• Non.mok.r. h.d norm.1 pulmonary functlonl. In SYW hou •• hold. prev.lenclI of re.plr.tory dl......, whHzlng on phy.lcal ex.mln.tlon, .nd Iymptom. of I.thma and chronic bronchltl., exceeded tho.eln the comp.rleon (Mlchlgln) popul.tlon, .v.n tor the younger daughter. Ind .on•• The.. dltt.renca., .nd Ilrw.y ob.tructlon and dl.trlbutlon detect. reported ,.rll,r were not expl.lned by clg.rette .moklng or by ••be.to ••xpo.ure. In.te.d, they .re tentatively I.crlbed to long-term expo.ure to Imbl,nt .Ir pollution In Lo. Ang..... (Arch'nt.,n Med 1188;148:2213-2220)

I

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The purposes of this article are firat, to relate the prevalences of signs of asbestosis in bystander worken and their household members to asbestos exposure in shipyards, age, and cigarette smoking. The presence and degree or asbestos disease between husband and wife .nd among various other family members is also compared. Second, the prevalences or cardiopulmonary diseases, pul· monary symptoms, and abnormal physiea1 findings in these workers and their household contacts are compared with a reference population from Michigan. Third, the degree or pulmonary functional impainnent is compared with the profusion of irregular opacities on male shipyard workers' (SYWs) chest radiographs. The pulmonary function results have been reported elsewhere and will be nferred to only briefiy in this article. I Finally, the knowledge of and reo sponse to perceived risks or asbestos exposure are assessed. -'\eeepted for publication MI~h 10. 1981i. From the l:nh·.nity of Southern Calitornia &hool ~ Medicine. Lo, Ancelet ,Dr Kilburn and Mr Warfha'A') and the Mount Sinai &boolof Mtdicine. Cit)" l'nh'enitr 01 Sey.· "fork (DT Thornton~ Reprint "'que~u to t:nh·.r.it~· of Southern California &bool of Medicine. :lO"lS Zonal Av•• Lot Ancel ••. CA 90033 IDr Kilburn).

Arch Int.rn Med-VoI146. Nov 1986

SUBJECTS AND METHODS This report concerns 338 male SYWs, 81 female SYWs, 280 r.t'es. 144 daughters, and 81 sona of workers. These households 1rtre recruited in )lay 1981, from the Long Beach-South Bay area of L1,'

4 71.1

110.'

2 70.5 1722 72.7 te.4 111.7' 120.8

117.1

117.0

W 8

17~.2

".7

..

17.1

110.1

126.8

ILl

.,.1

au

~

te.1

82.4

Table 10.-:-P!Jlmonary Function (as Percent Predicted) for Degree of Profusion of Irregular Ollacities. Intemational Labor Office Categories. in Male Shi\lY8rd Workers Who Had Ever Smoked Ciga,.ttes (n. 222)·

crl

18 1203 173.5

58

em

~kg

11.1

.1.4

FVC

17.11

10.0

FEY,

•.7

•.0

Aae.'1 Haighl.

71.1 70.• as.7 82.1 88.2

11.1

71 .•

171.7 81.0 19.1 11.1 71.1

13.1

10.0

111

1.10 41 12.1 173.7

13.1 170.7

t742

15.1

11.4

13.1

87.7

81.1

• .3

71.'

7U 70.3 52.5 7'5.0 eo.1 • .3 92.0

~

72.7

>111

12

".4

59.2 17.• 13.3 78.2 75.' NJI •.0 84.2 78.2 71.1 TOY 93.3 10.8 19.11 14.5 aFVC indicate. forced vital capacity; FeY,. forced expiratory volume in 1 I: FEF..", forced expiratory flow in 25 to 75 lecondl: FEF_. forced expiratory flow in 75 to 15 uconcta: DLCO. diffusing capacity for carbOn monoxide; ALY. lMoIar gas volume: and TOY. ltIorllCiC GU volume.

FEF.." FEF,.. DlCO

aFVC Indica'" forced vita' capacity: FEV,. forced expiratory Wlume In 1I: FEF.. ". ton:ed exPiratory flow in 25 to 7'5 NCOndI: FEF_. IOrcecI expiratory flow in 75 to 15 leconds; OleO. ditMlng capacity tor catton monoxide; ALY. IMIOIar gas volume; and TGV. ItIcnCiC gas volume.

CIIQp

MI 51 58.3 172.5

No.

71.0

.1.5

Table H.-Prevalences of Currant Cigarette SmokIng. ex-smoking.1tId Nonsmoking in Wortcel'l and Family Membel'l Male IhiP'IWd WOI1tIrI . . . . 1IhIP;II'd . . . . .

......... NoC"lij

~No~

eumnt . . . . . 110 C%)

1bIII

13 118.1)

111 (58.5) 11 CZUl 58 (20.0)

14 (24.')

338

(47.1)

r:T (1U)

41 (33.3)

(58.') 154 (31.0) 243 150.0)

14 (17.2} 157 (31.1) 10 (11.5)

" (5U) 149 (53.2)

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•

Sons

.a

..... MIchIgtn ~ IlI'IIiI'tId random ...... ~ Michigan populClon I1rDII«t random ..-.pIe

shortness of breath were considered maJor risks to the worker by approximately half or family members. There were fewer (55'i) who were a\\-are of an asbestos disease hazard for families. Specific risks for caneer and shortness of breath were known by 40'i, and other risks by 35,*,. Female SYWs who were ex-smokers had the lowest awareness of hazards for workers and for families. More inCormation about asbestos hazards and how to deal with them was requested by two thirds or workers and family members. Written communications were preferred over meetings or films. One fourth thought information should be in languages other than English. The question: "Do you consider youneif to be in good health?" was answered "ye:f' most frequently by sons and daughters, less so in wives, and lowest in female and male SYWs. Although 57,*, or male SYWs bad had a pre\;ous examination for asbestosis, only 7" of female SYWs, SC} of wives, and no children had been so examined. Over half of the examinations of SYWs had been done at the work site, most during a 1976 prevalence survey for asbestosis. \0 However. concern for health as indicated by periodic health examinations. was high in male and female SYWs and in wi\"es; about SOc} of these had been examined within the past year. Fewer sons and daughters had undergone health examinations. COMMENT

The male SYWs who had begun employment 20 or more years earlier. had a pre\"llience of asbestos disease midway between the peak level of 84" reported in ship repair workers studied at least 20 years, but mostly over 30 years, 221.

Arch Intern Med-VcI146. Nov 1186

" (22.2) 75 (28.1)

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,

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zao

21 (25.1)

'"81

(37.4)

G7'

163 (33.5)

488

1.

after initial exposure (in Baltimore), U and onevels reported in Connecticut (50"),11 in an earlier study of current workers only in Long Beach (37%),· and in San Francisco area shipyards (56%).11 The severity of pulmonary asbestosis in the male SYWs in Long Beach, as assessed by profusion of opacities on chest radiograph USing ILO pneumoconiosis criteria, was below that or Baltimore SYWs who had worked longer after initial exposure, U and of the Paterson, NJ, insulation manufacturing workers. UI Family Memben.- Wives, sons, and daughters had prevalences of asbestos disease that were higher, by an order or magnitude defined radiographically, than did the reference populations from Long Beach and Michigan.' Thus, it appeared that households in which the shipyard workers themselves were the major souree of asbestos provided sufficient exposure to produce radiographic signs of asbestosis in the lungs andlor pleura in family members. Most of these SYWs were bystanders of asbestos application or removal at work. Differences in prevalences are expected, considering that these SYWs had relatively less exposure. Their prevalence of asbestosis was one third as high as that of Paterson asbestos insulation factory workers .... Wives and children of the two groups differed to a similar extent. Paterson cohort members were older and had presumably high asbestos levels in their households. The time elapsed from initial exposure may be a more important variable than is exposure level in producing asbestosis at profusions of lJl or less. This is suggested by the stepwise increases in the prevalence of asbestosis in older SYWs born earlier with a peak at 39 years after exposure. An increasing prevalence of asbestosis in older Asbestos-Kilburn et al

Table 12.-Awareness of Asbestos Hazards. Self'Assessment 01 Health. Previous Health Examinations. and PreVIOUS ExamInatIOns tor Aabestosis in Shlpyara WOrXers and The., Housenola Contacts

WOrtc-te1alld IIeaIth For c:anc:er?

III. Shlpprd ___ .ow.

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73

87 47 41

IS

74

58

41

55

54 41 43 118

52

44 1,7

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It 71 71

.... ..

41

59

l1li

7S

ward-

For lnot1neSl 01 brulh?

...... ow.

49

51 l1li

AlltMNtW:llIIMIIII\IZ.II'd tar IImiIeI For cancWP For ~ d brNIh?

1,7

Hazard 10 worker. wry high?

17

HlzMiIO fImIII. wry high?

II

.. monI inbmation needed?

70

•

57

1

Do ,011 CCII'IIIidIr VOUfIIIIIO be In good hIIIII'I PnMouI Ubes1Dsia exalTllMliol'l?t PwIodic ~ ~ wIINn ~

1,2

72

you aware of any .ol'tc·related llealtl\ hazards 11\11 attect II'Ilpyerd .orll.,.? " tHaw you be.n examined before for ubee101·rellled probleml? ~aw PlI'Ied • periOdic l'Iealtl\ examinaon Within" put ~r1 -ANI

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, f 1

t

wives (those born in earlier decades) eonfirmed this temporal trend in that the time elapsed from initial exposure, ie, a long residence time in the chest, appears to have increased the effect 01 a given dose of asbestos. Unfortunately, in this Itudy, there is no way of assessing the relative eontributions of time VI dose. The high prevalence 01 pleural asbestos disease in older male SYWs suggelts that such changes develop 30 or more years after exposure to relatively low asbestos levels. The doubling of prevalence of asbestos signs from 1931 to 1940 and from 1921 to 1930 emphasizes the importance 01 the "latent period- during which fibrosis is developing but has not yet beeome recognizable on radiofr&phs. Both female SYWs. who presumably had even less exposure than male SYWs, and wives with signs of asbestosis had higher relative prevalences of irregular opacities in the lung compared with pleural signs. In fact, the proportion was almost double. Although this could be a sex difference, at least part of the problem lies in correctly distinguishing small opacities in the lung fields on the radiograph from ductile breast tissue. More chest radiographs on women exposed to asbestos, in comparable doses with those for men, are needed to settle the sex difference issue. The lower prevalence of asbestosis in black workers and their household contacts seems attributable to most 01 them being in younger age groups, that is, in the 1931 to 1940 decade 01 birth for workers. Familial It is presumed that insulators had greater exposure to asbestos-containing products than other SYWs and transported more asbestos home on their clothing. Insulators headed six of 24 families in which wives had asbestosis and two of six families with children who had asbestosis; yet they comprised less than l~ 01 SYWs. This sample of positive families is sufficiently large to establish that a risk existl, but the all-volunteer nature ofthe group studied and the small numbers of children who are positive make projections of prevalence speculative. A population-based study is needed. Medical HiitOry, R.lplratory Symptoml,

and PhYllcal Flndlngl The higher prevalences of pre\'iously diagnosed respiratory diseases in this population, as compared with those in a Arch Intlrn MecI-VoI148. Nov 1988

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52

31 42 70

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51

11

18

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0 40

va. for cancer? " va. for II'IOt1neII d

Dlufhtin.ow.

• • • 37 17 12

1

1,7

bIUIh?

stratified random lample of the Michigan population, are not attributable to difl'erences in cigarette Imoking. nor do they appear to be related to the usual effect. 01 asbestos. The finding that finger clubbing occurred largely in current smokers is not easily explained and deserves attention in future population Itudies. Respiratory diseases bad been diagnosed more frequently in the older pupa. workers and wives; however, the sons and daughters who were younger than the Michigan population also had his.her prevalences 01 asthma, chronic bronchitis, dyspnea on having climbed two flights of stairs, sputum production, chronic bronchitis by c:riteria, wheezing, and chest pain than did Michigan groups. These data plus substantial reductions in pulmonary function (with reduced airflow and altered distribution) suggests that the difference is due to an environmental influence, for which the best candidate il ambient air pollution, Los Angeles smog. Increased prevalences of wheezing and reduced breath sounds would also fit this hypothesis. An alternate explanation, that the recruited volunteers were already burdened by more respiratory illnesses, symptoms, and signs. and were not representative of the SYW-family population, must be eonsidered. This seems less likely, because most of the probandi postulated as ill were accompanied by one to five family members. There is little evidence that these illnesses are familial. Thus, recruitment of over 1000 subjects within families for evaluation of asbestosis through 360 wives and female SYWs would not appear to bias selection toward nonoccupational pulmonary disease. Finally, in our clinical judgment based on the interviews, the reported chest pain is infrequently angina, but rather renects tracheobronchial irritation probably due to ozone in smog. In summary, all respiratory illnesses were more prevalent in these people than in the lfichigan men and women. To explain these differences, chronic exposure to the ambient air pollution 01 Los Angeles is postulated. A follow-up study of the women in this population for four-year interval changes would provide data to support or deny this possibility. Pulmonary Function

Only slight functional impairment accompanied the relatively mild asbestosis in these SYWI and family members. I As expected, current and ex-cigarette smokers were more impaired than nonsmokers. Impairment was more marked Asbestos-Kllbum It aI

221.

.

• I

when fine irregular opacities had a proi'Jsion grea~t!' :han 110. In contrast, ~omewhat older nonsmokers shcTed no gradients of impairment with increasing profusion r:f : paci. ties. In fact. it appears that asbesto15is of profusion .-:-ade 1 does not decrease pulmonary function in nonsmokerS. HoW" e"'er, the numbers are too small to confirm this con,'t..:ture. Also. the nonsmokers who were older. and had: 1 and greater profusion of fine irregular opacities. mar ha\'e shown less functional impairment because of ha7'.ng a greater pulmonary endowment, the "healthy wor:Ur ef· Cect," and being "sun'hoors," Adverse etreets of ciprette smoking on expiratory a.irflow appear to be sOl!:oC!what opposed by the fibrosis of asbestosis, Thus. these puameters are not reduced to the same degree as ~ in cigarette smokers who have not been expOsed to asbestos or developed asbestosis. II Awaren... of Aabe.to. Huard. end ....Ith AttltuOll

Cessation of smoking may be related to percep:ion of health risk in asbestos-exposed subjects, Clearly. ~ proportion of ex-smokers in these subjects was well abc7re that for the Michigan population sample for all groups, ineuding daughters and sons, The proportion of current smoUrs is below present national prevalences as weU. Their achievement is tempered by the continuing high risk fer lung cancer in the early years after cessation of smokin(. The persisting smokers clearly need additional assistance to quit smoking. We do not know whether ex-smoken quit because of awareness of hazards, or because of symptoms, andlor respiratory impairment. Since the predocinant

1. Kilburn KH. Wanhaw R. Thomton JC: PIllmolW7 fwletionL :.mpairment IDd symptoms iD women iD the Loa Ancelel harbor area. A" I JlfIl

1985;79:23-28. 2. Selikotr U, Andenon HA: A SM1WV