Occupation and prostate cancer risk in Sweden

To provide new leads regarding occupational prostate cancer risk factors, we linked 36,269 prostate cancer cases reported to the Swedish National Cancer Registry during 1961 to 1979 with employment information from the 1960 National Census. Standardized incidence ratios for prostate cancer, within major (1-digit), general (2-digit), and specific (3-digit) industries and occupations, were calculated. Significant excess risks were seen for agriculture-related industries, soap and perfume manufacture, and leather processing industries. Significantly elevated standardized incidence ratios were also seen for the following occupations: farmers, leather workers, and white-collar occupations. Our results suggest that farmers; certain occupations and industries with exposures to cadmium, herbicides, and fertilizers; and men with low occupational physical activity levels have elevated prostate cancer risks. Further research is needed to confirm these findings and identify specific exposures related to excess risk in these occupations and industries.     

Occupational exposure to chemicals and risk of thyroid cancer in Sweden

Purpose  To explore thyroid cancer (TC) risk in the Swedish population, associated with occupational exposure to certain chemicals. Methods  National cancer and death registries were used to follow-up (1971–1989) all Swedish workers employed in the 1970 census. Each combination of occupation and industry was linked to a Swedish job-exposure matrix (JEM), with exposure to 13 chemicals classified as “possible exposure”, “probable exposure” or “unexposed”. Relative risks were obtained using Poisson models adjusted for age, period and geographical area. A second analysis was performed, in which adjustment was additionally made for simultaneous exposure to other matrix chemicals and ionising radiations. Results  Probable exposure to solvents among women displayed an increased risk (RR = 1.91; 95%CI:1.05–3.45), mainly due to a higher risk observed among shoe-cutters, lasters and sewers engaged in shoe-making. Conclusions  Exposure to solvents, used mainly in the shoe and leather industry, seems to be associated with excess TC among women.     

Occupation and pancreatic cancer risk in Louisiana

To study the relation of occupational exposures and pancreatic cancer, we evaluated data from males (198 cases and 209 controls) participating in a hospital-based case-control study conducted in a high-risk area of Louisiana between 1979 and 1983. The questionnaire obtained information on lifetime occupational history, as well as dietary, smoking, and drinking habits and demographic characteristics. After adjustment for smoking and dietary patterns, white collar occupations showed consistent elevations in risk, whereas associations for other occupations were in general unremarkable. Although not significantly elevated, risks for truck drivers (OR = 1.7) and those with long-term employment in machine repair or as mechanics were suggestive (OR = 2.5). No association was found for jobs in oil refining or oil and gas extraction (ORs were 0.5 and 0.4, respectively), although risks were slightly elevated for long-term workers in the chemical processing industry (OR = 1.2). While these associations deserve further study, our findings are consistent with results of other studies which do not suggest that occupational exposures are important determinants of pancreatic cancer.     

Occupation and bladder cancer risk.

This study examines the estimated risk of bladder cancer associated with various occupations among 1,465 cases identified in Orange County, California, during 1984-1988. The annual age-adjusted incidence rate per 100,000 population in Orange County was similar to that of the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute: 25.7 in males and 6.2 in females. Cases were compared with a sample of Orange County residents relative to broad category of current occupation, adjusted for age and cigarette smoking. The estimated relative risks were significant for males in machine trades (relative risk (RR) = 2.69, 95% confidence interval (CI) 1.24-5.82) and processing occupations (RR = 5.77, 95% CI 1.43-23.27) and for females in machine trades (RR = 8.34, 95% CI 1.14-61.17) and homemakers (RR = 5.37, 95% CI 2.40-11.99) as compared with individuals of the same sex in professional, technical, and managerial occupations.     

Occupation,exposure to chemicals and risk of gliomas and meningiomas in Sweden

BACKGROUND: Occupational exposures may be related to the development of brain cancer. The objective was to estimate occupational-specific risk of gliomas and meningiomas among Swedish men and women gainfully employed in 1970 over the period 1971-1989, and the influence of occupational exposure to chemical substances. METHODS: A dataset linking cancer diagnoses from the Swedish national cancer register to occupational and demographical data obtained in the 1970 census was used to fit log-linear Poisson models, in order to obtain relative risks adjusted by age, period, geographical area and town size. Exposure to 13 chemicals was assessed using a Swedish job-exposure matrix. RESULTS: The main findings of this study among men were the increased risk of glioma with occupational exposure to arsenic, mercury, and petroleum products and of meningioma with lead. Women in occupational sectors with a higher socio-economic status showed an increased incidence of both, gliomas and meningiomas. CONCLUSIONS: Occupational exposure to some chemicals appeared to be related with an increased risk of glioma and meningioma in men. Exposures involved in glioma and meningioma development seemed to be different.     

Occupation and risk of stomach cancer in Poland

Background: In spite of the dramatic decline in the incidence of stomach cancer in the twentieth century, Poland has one of the highest rates in the world.     

Occupation and the risk of bladder cancer

The relationship between bladder cancer, occupation and exposure to a number of occupational agents was assessed in a case-control study conducted in the greater Milan area, Northern Italy. The case series consisted of 263 cases (219 males, 44 females) with histologically confirmed invasive bladder cancer, admitted to a network including major teaching and general hospitals in the area under surveillance. The controls were 287 patients (210 males, 77 females), admitted for acute, non-neoplastic or urinary tract diseases to the same network of hospitals. Cases more frequently reported occupation in dyestuff production (relative risk (RR) = 4.6), painting/spraying work (RR = 1.8), chemical industry (RR = 1.7), pharmaceuticals (RR = 1.7) and coal/gas production (RR = 3.1). Only for dyestuff production however, was the excess statistically significant. There was no association with agriculture or related activities, rubber manufacturing, printing, the petroleum industry, food processing and mechanics. In relation to exposure to occupational agents, significant positive trends in risk were observed for dyes/paints (RR = 4.8 for greater than ten years of exposure), herbicides (RR = 4.1), chemicals (RR = 2.4) and gases/fumes (RR = 4.8). No association was found with metals or metal dusts, plastic resins or glues, oil, wood dust, solvents or benzene, asbestos, electricity or radar and coal tar. Besides confirming the well known association between bladder cancer risk and dyestuff production and, to a lesser extent, a wide spectrum of chemical-related activities, this study provides statistically significant evidence of an independent role of herbicides on the risk of bladder cancer.(ABSTRACT TRUNCATED AT 250 WORDS)     

Occupation and male lung cancer: a case-control study in northern Sweden

Using a case-control study comprising about 600 men with lung cancer in northern Sweden the potential risk of different occupations and groups of occupations was studied. Longitudinal data concerning occupation, employment, and smoking habits were obtained by questionnaires. Some occupational groups (underground miners, copper smelter workers, electricians, and plumbers) exposed to previously known lung carcinogenic agents such as radon daughters, arsenic, and asbestos, had considerably increased odds ratios, which persisted after adjustment for smoking. A slightly raised odds ratio was observed in a group of blue collar workers potentially exposed to lung carcinogenic agents; this rise in the group as a whole mainly disappeared after adjustment for smoking. Farmers and foresters had strikingly low odds ratios, which could only partly be explained by their more moderate smoking habits. The population aetiological fraction attributable to occupation was estimated as 9%.     

Occupation and the risk of laryngeal cancer in Uruguay

In a case-control analysis involving 112 patients afflicted by laryngeal cancer and 509 controls diagnosed with cancers not related to tobacco and alcohol exposures, we studied the effects of type of employment and of substances present in the workplace on laryngeal cancer risk. Effects were measured relative to those never employed or never exposed to the substances. All analyses were controlled for age, tobacco smoking, and alcohol drinking through unconditional logistic regression and stratified analysis. Among job titles, butchers, vintners, bakers, and car assemblers presented elevated risks of laryngeal cancer (OR for butchers 2.8, 95% CL 1.1–7.2). Similarly, asbestos, mists from strong inorganic acids and pesticide exposures were associated with increased risks of laryngeal cancer (OR for strong acids 1.8, 95% 1.1–2.9). Am. J. Ind. Med. 33:537–542, 1998. © 1998 Wiley-Liss, Inc.     

Occupation and the risk of laryngeal cancer in Turkey

OBJECTIVES: A hospital-based case-referent study was conducted in Turkey to provide further information on occupational risk factors and laryngeal cancer. METHODS: Among 7631 cancer cases seen at an oncology treatment center between 1979 and 1984, 958 laryngeal cancer cases were identified among men. Occupational history, tobacco and alcohol use, and demographic data were obtained from patients with a standardized questionnaire. Special 7-digit standard occupational and industrial codes were created to classify the job and industrial titles of the subjects. After exclusions, 940 laryngeal cancer cases and 1519 referents were available for study. Age-, smoking- and alcohol-adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. RESULTS: Excess laryngeal cancer occurred among guards (OR 1.5, 95% CI 1.1-2.1), production supervisors (OR 1.8, 95% CI 1.1-3.1), textile workers (OR 1.9, 95% CI 1.2-3.3), drivers (OR 1.7, 95% CI 1.1-2.4), construction workers (OR 1.7, 95% Cl 1.2-2.6), and workers in grain mills (OR 3.1, 95% CI: 1.3-7.6), trade unions (OR 3.6, 95% CI: 1.1-11.7) and local government services (OR 4.7, 95% CI 1.7-12.5). Supraglottic cancer was excessive among the textile workers, construction workers, and local government laborers, all with potential dust exposure. The risks of the general managers, electricians, and workers from industries such as pharmaceutical production, industrial machinery production, electric utilities, and retail services were lower than expected. CONCLUSIONS: The risk of laryngeal cancer was associated with several occupations, and supraglottic larynx cancer appears to be more common among workers in dusty occupations and industries.     

Occupation and male lung cancer: a case-control study in northern Sweden.

Using a case-control study comprising about 600 men with lung cancer in northern Sweden the potential risk of different occupations and groups of occupations was studied. Longitudinal data concerning occupation, employment, and smoking habits were obtained by questionnaires. Some occupational groups (underground miners, copper smelter workers, electricians, and plumbers) exposed to previously known lung carcinogenic agents such as radon daughters, arsenic, and asbestos, had considerably increased odds ratios, which persisted after adjustment for smoking. A slightly raised odds ratio was observed in a group of blue collar workers potentially exposed to lung carcinogenic agents; this rise in the group as a whole mainly disappeared after adjustment for smoking. Farmers and foresters had strikingly low odds ratios, which could only partly be explained by their more moderate smoking habits. The population aetiological fraction attributable to occupation was estimated as 9%.     

Occupation and lung cancer risk in Leningrad Province, Russia

To investigate the association between occupation and lung cancer risk in Leningrad Province, Russia, we identified 540 pathologically diagnosed lung cancer cases (474 males and 66 females) and 582 controls (453 males and 129 females) from the 1993-1998 autopsy records of the 88 state hospitals of the Province. Lifetime occupational histories were obtained from personal records coded according to the standard Russian occupational classification system. Lung cancer risk was increased in workers in the manufacturing industry, particularly in the food industry and wholesale/retail trade and in the miscellaneous manufacturing industry. An increased risk was also found in subjects employed in chemical and metal production for 10 years or more. When we considered the association between specific occupations and lung cancer, waste incineration operators and loaders exhibited an excess risk that increased with employment duration. The present study, which is the first to evaluate the risk of lung cancer by occupation in Russia, suggests the presence in Leningrad Province of exposure in the workplace to lung carcinogens that require further characterization to develop targeted and effective preventive measures.     

Occupation and lung cancer risk among women in Northern China

Lifetime occupational histories were obtained in a case-control study of 965 female lung cancer patients and 959 controls selected from the general population in Shenyang and Harbin, People's Republic of China, where most women have worked outside the home. After adjusting for smoking, we found a significantly increased risk of lung cancer associated with employment involving the manufacture of transportation equipment (OR = 1.6, 95% CI = 1.0, 2.6), in particular the manufacturing of automobiles (OR = 3.0, 95% CI = 1.4, 6.4). Metal smelting and treatment workers were at an increased risk of lung cancer (OR = 1.5, 95% CI = 1.0, 2.1); the highest risks were observed among metal surfacers (OR = 3.1, 95% CI = 1.1, 9.0) and currently employed foundry workers (OR = 13.0, 95% CI = 1.7, 99.4). On the other hand, about a 50% decreased risk of lung cancer was observed among those employed in textile industries or as leaders of state and party organizations. Based on self-reports, exposures to coal dust and smoke from burning fuel at the workplace were also significant risk factors. The findings were similar when the analyses were confined to nonsmokers and were comparable across the major cell types of lung cancer. © 1993 Wiley-Liss, Inc.     

Occupational exposure to ionizing radiation and electromagnetic fields in relation to the risk of thyroid cancer in Sweden

OBJECTIVES: This study sought to ascertain the risk of thyroid cancer in relation to occupational exposure to ionizing radiation and extremely low-frequency magnetic fields (ELFMF) in a cohort representative of Sweden's gainfully employed population. METHODS: A historical cohort of 2 992 166 gainfully employed Swedish male and female workers was followed up from 1971 through 1989. Exposure to ELFMF and ionizing radiation was assessed using three job exposure matrices based on industrial branch or occupational codes. Relative risks (RR) for male and female workers, adjusted for age and geographic area, were computed using log-linear Poisson models. RESULTS: Occupational ELFMF exposure showed no effect on the risk of thyroid cancer in the study. However, female workers exposed to high intensities of ionizing radiation registered a marked excess risk (RR 1.85, 95% confidence interval (95% CI) 1.02-3.35]. This trend was not in evidence among the men. CONCLUSIONS: While the study confirms the etiologic role of ionizing radiation, with a higher incidence of thyroid cancer being recorded for the most-exposed female workers, our results do not support the possibility of occupational exposure to ELFMF being a risk factor for the development of thyroid cancer.     

Occupation and smoking as risk determinants of lung cancer

The standardized incidence ratio (SIR) of lung cancer was determined for different occupational groups in Finland. The data on all cases of lung cancer diagnosed in Finland in age groups of 35-69 years in 1971-1975 were supplemented by information on occupation from the 1970 census (Central Statistical Office). The expected numbers of cases were based on the sex, age and occupation-specific numbers of person-years computed in the Central Statistical Office, and sex- and age-specific incidence rates of lung cancer among the economically active population (as defined 1 January 1971). Compared with the risk of the total economically active population, the relative risk of those not active (SIR) was 1.69 for men and 0.86 for women. Lower than expected relative risks were encountered among highly educated and white-collar male workers (religious, legal, pedagogical, medical, technical and administrative work), in sales work, transport service work and among farmers. High SIRs were found in mining and quarrying, forestry, woodworking (joiners), construction, painting and among unskilled workers. Among women the numbers of cases were small and only one significant SIR was obtained; the risk was lower than expected in farming. Data on the smoking habits of males in different main occupational categories in Finland show that variation between different occupational groups in the prevalence of smoking closely corresponds to that in the SIR for lung cancer (R = 0.96).     

Occupation and risk for testicular cancer: a case-control study

A case-control study of 271 testicular cancer cases aged 18-42, including 60 seminomas and 206 other germinal cell tumours, and 259 controls was carried out to study the association between occupation and testicular cancer risk. Study subjects were identified at three medical centres, two of which treat military personnel. Controls were men diagnosed with a cancer other than of the genital tract. Associations were identified between professional employment (administrators, teachers and other professionals) and risk for testicular seminoma, OR = 2.8 (95% Cl: 1.4-5.4) and between employment in production work and risk for other germinal cell tumours, OR = 1.8 (95% Cl: 1.1-2.7). No specific occupations within these broad groups were responsible for observed increases. Self-reported exposure to microwave and other radio waves was associated with an excess risk for both seminomas and other germinal cell tumours. However, an assessment of radio wave exposure based on job title did not support this finding. Although testicular cancer has been increasing in recent decades among young males, occupational factors did not appear to account for a substantial proportion of testicular cancer occurrence in the population studied.     

Occupational exposures and the risk of ovarian cancer in Sweden

BACKGROUND: Studies of occupational exposures and ovarian cancer, often limited by few subjects or proportionate mortality data, have yielded inconsistent results. METHODS: Swedish women employed in 1960, 1970, or during both years were followed from 1971 to 1989 using census data linked to nationwide cancer and death registries. A total of 9,591 ovarian cancer cases were identified among 1,670,517 women. Poisson regression was used to estimate the relative risk of ovarian cancer in specific occupational groups and in women exposed to particular occupational exposures defined by job exposure matrices. We lacked data on reproductive factors. RESULTS: Jobs associated with elevated ovarian cancer rates in this and previous studies include dry cleaning, telegraph and telephone work, paper packaging, and graphic and printing work. In contrast to results of some previous studies, we found that hairdressers and beauticians were not at increased risk of ovarian cancer. Organic dusts, aromatic amines, aliphatic and aromatic hydrocarbons are suggested as specific etiologic agents. CONCLUSIONS: In this large study, we have confirmed some results from smaller studies and identified some new relationships that need to be confirmed elsewhere.     

Occupation as a risk identifier for breast cancer.

OBJECTIVES. Breast cancer mortality may be reduced if the disease is detected early through targeted screening programs. Current screening guidelines are based solely on a woman's age. Because working populations are accessible for intervention, occupational identification may be a way of helping to define and locate risk groups and target prevention. METHODS. We used a database consisting of 2.9 million occupationally coded death certificates collected from 23 states between 1979 and 1987 to calculate age-adjusted, race-specific proportionate mortality ratios for breast cancer according to occupation. We performed case-control analyses on occupational groups and on stratifications within the teaching profession. RESULTS. We found a number of significant associations between occupation and frequency of breast cancer. For example, white female professional, managerial, and clerical workers all had high proportions of breast cancer death. High rates of breast cancer in teachers were found in both proportionate mortality ratio and case-control analyses. CONCLUSIONS. These findings may serve as in an aid in the effective targeting of work-site health promotion programs. They suggest that occupationally coded mortality data can be a useful adjunct in the difficult task of identifying groups at risk of preventable disease.