Association of lung cancer and airway particle concentration Churg A, Stevens B. Department of Pathology, University of British Columbia, Vancouver, BC. Environ Res 1988;45:58-63.

Using 15 autopsy lungs containing nonresected lung cancers, we evaluated the exogenous mineral particle content of the upper and lower lobeparenchymaandoftheupperandlowerlobebronchialmucosa.The bronchial mucosa from the lobe with the cancer was found to contain about three times the median mineral particle load of the bronchial mucosa from the lobe without the cancer, a statistically significant difference. No such difference was seen for mineral content of the parenchyma. This observation suggests that mineral particle deposition or accumulation in the bronchial mucosa may be related to respiratory carcmogcnesls.

Cancer in the respiratory organs of Swedish farmers. Wiklund K, Steineck G. Department of Cancer Epidemiology, Karo- linska Ifospilal. S-10401 Stockholm. Cancer 1988;61: 1055-8.

In a cohort of 254,417 male Swedish farmers (4,330,717 person- years) the incidence of cancer of the respiratory organs was compared to a reference cohort of 1,725,845 men (30.131.664 person-years) employed in othereconomic activities than agriculture or forestry. In the study cohort 1450 cases of cancer in the respiratory organs were found in 1961 to 1979 resulting inan estimatedrelativerisk (RR) of0.38(95% confidence interval [CI]: 0.36-0.40). For cancer of trachea, bronchus and lung, the decreased risk was equal for adenocarcinoma and squamous cell carcinoma. No time related trend in RR for any of the histologic subtypes could be seen. However, for squamous cell carci- noma in nose and nasal sinuses RR has increased from 0.42 (95% CI: 0.20-0.80) in 1961 to 1966 to 2.06(95% CI: 1.22-3.50) in 1974 to 1979.

Passive smoking and lung cancer: A publication bias? Vandenbroucke JP. Deparmzem of Clinical Epidemiology, University Hospital, 2300 RC Leiden. Br Med J 1988;296:391-2.

To assess the likelihood of publication bias in a recent review of the effectofpassivesmokingonlungcancertheevidencefromthereviewed papers wasvisualisedon a ‘funnel’plot. In suchaplotiftherelativerisks from various studies are plotted according to sample size they should scatter round some underlying true value, the scatter being greatest where the studies have the lowest statistical power - thus showing a ‘funnel’ pattern. If there is publication bias and studies with non- significant results are not being published there should be a ‘gap’ in the plot. The logarithm of the relative risks was plotted against the standard error of the logarithm of the relative risk (which was used instead of sample size as a measure of statistical uncertainty). The resulting plot was compatible with a publication bias but only in studies on men. Further studies of passive smoking and lung cancer in men seem to be warranted.

Lung cancer mortality (1950-80) in relation to radon daughter exposure in a cohort of workers at the Eldorado Port Radium uranium mine: Possible modification of risk by exposure rate. Howe GR, Nair RC, Ncwcombe HB, Miller AB, Burch JD, Abbatt JD. Epidemiology Unit. National Cancerfnslitute of Canada, Universilyof Toronlo, Toronto, Ont. MSS IA8. J Nat1 Cancer Inst 1987;79:1255-60.

A cohort study of 2,103 workers employed between 1942 and 1960 ata uranium mine in the NorthwcstTerritories,Canada, was conducted. A total of 57 lung cancer deaths was observed (expected = 24.73, P < .OLlOl). There was a highly significant linear relationship between exposure and increased risk of lung cancer, giving estimates for the relative and attributable risk coefficients of 0.27 per working level month (WLM) and 3.10 per WLM per 106 person-years. These risk coefficients were substantially less than those estimated from the experience of miners in the Bcaverlodge mine, which have previously been reported. Any biasesintheprcsentestimatesarelikely tohavebeen

upward, and therefore they probably represent an upper limit. The major difference between the two mine cohorts is in the exposure rate, since the Port Radium miners were exposed to much greater concentrations of radon daughters than the Beavcrlodge miners. It is postulated that risk of lung cancer from radon daughter exposure may be modified by exposure rate, for which hypothesis there is some support from other epidemiologic data.

Asbestos exposure-cigarette smoking interactions among shipyard workers. Blanc PD. Golden JA, Gamsu G, Aberle DR. Gold WM. Division of Chest Medicine, University of California, San Francisco, CA 94143. J Am Med Assoc 1988;259:370-3.

We studied the roentgenograms, pulmonary function tests, and physical findings of 294 shipyard workers to evaluate asbestos expo- sure-cigarette smoking interactions. Roentgenographic parenchymal opacities, decreased pulmonary diffusing capacity for carbon monox- ide, decreased flow at low lung volume, rales, and clubbing were each significantly related to the number of years elapsed since first exposure to asbestos and cigarette smoking status when analyzed by logistic regression. A dose-dependent cigarette smoking response that was consistent with synergism was present only for parenchymal opacities and decreased flow at low lung volume. These findings suggest that decreased flow at low lung volume, possibly reflecting peribronchiolar fibrosis, may be a functional corollary to smoking-associated parenchy- ma1 roentgenographic opacities among some asbestos-exposed indi- viduals.

Case-control study of lung cancer in civilian employees at the Portsmouth Naval Shipyard, Kittery, Maine. Rinsky RA, Melius JM, Homung RW et al. Nafional lnsrifute for Occupafional Safety and Healfh. Cincinnafi, OH 45226. Am J Epide- miol 1988;127:55-&1.

Case-control analysis of deaths due to lung cancer (International Classification of Diseases, Eight Revision, code 162) among persons whoworkedatIhePortsmouthNavalShipyard,Kittery,Maine,between 1952 and 1977 found elevated odds ratios for exposures to ionizing radiation, asbestos, and welding by-products. The radiation-related excess was statistically significant in persons with cumulative lifetime exposures of 1.0-4.999 rem. When asbestos and welding histories were combinedintoasingleriskfactor,oddsraliosforthecombinedexposure were significantly elevated for two of three duration-of-exposure cate- goriesexamined.Furthcranalysisofdalaonradiationexposure,control- ling for exposures to asbestos and welding, found reductions in initial estimates of radiation risk at all levels of radiation exposure. This reduction suggests that radiation workers were more heavily exposed to

asbestos and/or welding fumes than were other workers and that those exposures confounded the observed association between radiation and lung cancer. Analysis of mortality by time since first exposure to radiation revealed no pattern of progressive increase as latency in- creased. By contmst, odds ratios for asbestos/welding increased with latency. Data on cigarette smoking and socioeconomic status were not available. Theresultsofthisstudydonotprecludeapossibleassociation between radiation exposure at the Portsmouth Naval Shipyard and excess mortality from lung cancer. However, they provide no evidence in support of such a relation.

Enzyme induction in rat lung and liver by condensates and fractions from main-stream and side-stream cigarette smoke. Pasquini R, Sforzolini GS, Savino A, Angeli G, Monarca S. Departmenr of Ilygiene, University of Perugia. I-06100 Perugia. Environ Res 1987;44:302- 11.

Aryl hydrocarbon hydroxylasc (AHH) and dlmethylnitrosamine