Document BRLVyaX7wzx4QMowJXkQ6JbEE

\0$6 Mourn-518 SOCIETY FOR EPIDEMIOLOGIC RESEARCH: ABSTRACTS with a history of abnormal pap smears) were excluded, was not increased among the 10 subjects thought to These findings support the possibility that long-term have had exposure over 1 ppm. In formaldehyde in- use of oral contraceptives may have an adverse effect duces nasal cancers in huraans, such an effect can not on the cervical epithelium, but emphasize the need for be detected by these methods, careful evaluation of confounding influences. v/. Optimal frequency of screening for cervical cancer, data from a Toronto case-control study. E. Clarke* (Dept, of Preventive Medicine and Biostatistics, U. of Toronto, Toronto, Ontario, Canada M5S 1A8), T. Anderson, and S. Hilditch. A study of 181 cases and 90S controls conducted in Toronto, Canada, between 1973 and 1976 demon strated that women who had not had a Papanicolaou smear in the last five years were at three times the risk of developing cervical cancer. The present report draws on this study wherein details and cervical smears obtained from attending physicians for 156 cases and 682 controls were analyzed to assess the optimal frequency of cervical screening. The time be tween the last norma! smear and the date of diagnosis was divided into 12-month intervals. Relative protec tion was then calculated comparing women who had one or more normal smears with those who were never screened. The results show a significant protective effect of cervical screening in women who had two or more normal smears, the last one being within two years of diagnosis. This trend, although not statisti cally significant, continued to four years prior to di agnosis, suggesting that screening intervals should not be less than four years. This study illustrates the effectiveness of the case-control approach in the eval uation of screening procedures. Mesothelioma risk related to occupational or other asbestos exposure: preliminary results from a casecontrol study. R. Spirtas* {NCI, Bethesda, MD 20205), R. Keehn, W. Wright, A. Stark, G- Beebe, and J3. Dickson. A study has been undertaken to evaluate occupa tional and other asbestos exposures as to the gradient of relative risk of malignant mesothelioma. It includes telephone-interviews with next-of-kin of cases diag nosed during 1975-1980 and matched controls from Los Angeles County, New York State (exclusive of New York City), and selected Veterans Administra tion Hospitals. Based upon histopathologic review by an international panel of expert pathologists, re sponses from next-of-kin of 259 confirmed cases and matched controls have been selected for preliminary analysis. Job and non-job-related activities with known or suspected asbestos exposures have the fol lowing odds ratios (mid 95% confidence intervals): furnace or boiler installation or repair, 4.5 (2.5~8.2); shipbuilding, ship demolition, or shipyard work, 4.3 (2.5-7-4); insulation, 3.2 (2.1--5.0); elevator installation or repair, 1.9 (0.4-9.8); building demolition, 1.4 (0.73.0); plumbing or heating repair, 1.3 (0.9-I.9); produc tion of textiles, 1.3 (0.4-4.9); brake lining installation or repair, 1.0 (0-6--1.6); production of paper products, 0.8 (0.3-1.9). Results axe reported by site (pleura, peritoneum), cell type (epithelial, biphasic, mesenchy Occupation and Environment 1 mal) and age at first exposure. Chairman; S- Prcston-Martin Mutagenic cervical mucus In women smokers. E. Formaldehyde-related occupations and cancers of the nasopharynx and sinonasal region. G. Roush,* J. Walrath, L. Stayner, S. Kaplan, and A. Blair (Yale U., New Haven, CT 065101). Formaldehyde vapor induces cancer of the nasal passages in laboratory animals. In this study, occu pational information was obtained for 198 persohs with sinonasal cancer and 173 with nasopharyngeal cancers, identiGed as incident cases by the Connecti cut Tumor Registry over 41 years among Connecticut males dying of any cause, and for 605 controls sampled from Connecticut death certificates. City directories and death certificates provided information on job, industry, employer and year of employment for expo sure classification. Without knowledge as to casecontrol status, an industrial hygienist (particularly experienced in epidemiologic studies offormaldehyde) classified each study subject with respect to probabil ity and degree of formaldehyde exposure. Elevated odds ratios observed in the rubber industry, printers, and physicians and dentists were consistent with ran dom variation. No associations for either ofthese two malignancies were detected in formaldehyde-related occupations in six other industries. There was no overall association of formaldehyde-related occupa tions with either nasopharyngeal cancers (odds ratio Holly,* N. Petrakis, N. Friend, D. Sarles, R. Lee, and L. Fiander (U. of California, San Francisco, CA 94143). A study was conducted to determine whether any relationship existed between mutagenicity of a wom an's uterine cervical mucus and her current smoking status. Cervical fluids obtained from 78 premenopau sal women seen between July 1983 and March 1984 at the University of California dysplasia and diethylstilbestrol clinic or in a private practice were tested for mutagenicity using the Ames/Sabnonella microsomal test. Fourteen of 36 current smokers (39%) had posi tive tests as compared to five of 42 nonsmokers (12%) (odds ratio (OR) " 4.7; 95% confidence interval (Cl), 1.6-14.2). Secretions from 13 of 31 women (42%) who had smoked within the previous six hours were posi tive on the laboratory test versus one of five women (20%) among those who bad smoked seven or more hours before the specimens were obtained (OR -- 2.9, 95% Cl, 0.30-27.6). Fluids from women with dysplasia or carcinoma in situ were more likely to be mutagenic than were those from other women (OR - 2.0; 95% Cl, 0.70-5.9). This relationship between smoking and mutagenic cervical fluids offers biochemical evidence for the association between cervical cancer and ciga rette smoking noted in previous epidemiologic studies. (OR) - 1.1; 95% confidence interval (Cl), 0.7-1.9) or with sinonasal cancer (OR -- 0.8; 95% Cl, 0.5-1.3). No Associations between nine sites of cancer and nine trends in risk were observed with time and age. Risk organic dusts: results from a hypothesis-generating i i i HWBUI0010189