Cancer mortality among a cohort of chromium pigment workers

A study of mortality among 1,879 male workers employed in a New Jersey chromium pigment factory was carried out, with follow-up from 1940 to 1982. Vital status of 1,737 (92%) of the eligible cohort members was determined. For all malignant neoplasms, 101 deaths were observed while 108.8 were expected, SMR = 93 (standardized mortality ratio; n.s.). For the entire study group, no significant excess was observed for respiratory cancer or cancer at other sites. However, the total number of years of employment in the factory and the total number of years of exposure to chromate dusts were both statistically significantly (p less than .05, for trend) associated with an increased risk for lung cancer. The excess risk for lung cancer associated with duration of exposure to chromate dusts was, however, only clearly apparent for subjects followed for 30 years or more after initial employment. For this group, the SMRs were 81, 139, 201, and 321 for the subjects with 0 years, less than 1 year, 1-9 years, and 10+ years of exposure to chromate dusts (p less than .01, for trend), respectively. The risk for digestive cancer was only weakly associated with exposure to chromate dusts.     

Cancer mortality among municipal pest-control workers

Objectives: This epidemiological study was carried out in order to investigate the hypothesis of a relationship between cancer occurrence and occupational exposure in a population of municipal pest-control workers exposed to a wide range of pesticides and other chemicals. Methods: The study was designed as a mortality historical cohort study. The cohort comprised all subjects ever employed in a municipal pest-control service between 1979 and 1994. The follow-up period lasted from 1979 to 2000. The mortality rates of pest-control workers were compared with those of a regional population. A job exposure matrix was developed, which took into account four types of chemicals: formaldehyde, ethylene oxide, insecticides and rodenticides. Results: None of the 181 subjects of the cohort, leading to 3,107 person-years, was lost to follow-up. Thirty-nine of them died, and all the causes of deaths were ascertained. The standardized mortality ratios (SMRs) for all causes of deaths and for all cancer causes were significantly greater than unity: 1.61 (1.14–2.20) and 2.24 (1.39–3.43), respectively. Non-significant excesses were observed for most cancer sites, except for lung cancer, which had a low SMR. We obtained significant excesses for cancer in workers with more than 20 years of employment [SMR=2.42 (1.43–3.82)]. Cancer mortality tended to increase insignificantly with formaldehyde and rodenticides exposures, whereas no clear patterns were observed for ethylene oxide and insecticides. However, significant excesses were observed for the highest exposure levels of formaldehyde, insecticides and rodenticides. Conclusions: This study showed a statistically significant excess of cancer mortality in a population of municipal pest-control workers exposed to a wide variety of chemicals. These cancer sites might be related to occupational activities, since they tended to be more frequently observed when duration of employment increased.     

Nonmalignant respiratory disease mortality among woodworkers participating in the American Cancer Society Cancer Prevention Study-II (CPS-II)

Nonmalignant respiratory disease (NMRD) mortality was examined among woodworkers participating in the American Cancer Society's CPS-II cohort study. During the 6-year prospective follow-up, there were 97 NMRD deaths among 11,541 men reporting employment in wood-related occupations and 1,338 NMRD deaths among 317,424 men reporting no exposure to wood dust or wood-related jobs. Relative risks, adjusted for age and smoking, were calculated using Poisson regression. A small excess of NMRD was observed among woodworkers. However, the relative risk was higher among woodworkers who did not report exposure to wood dust (RR = 1.52, 95% CI = 1.18–1.97) than those who did (RR = 1.27, 95% CI = 0.91–1.77), and no clear trend with duration of exposure was observed. An excess of NMRD was observed among woodworkers reporting exposure to asbestos (RR = 1.59, 95% CI = 0.85–2.96), as well as the small number of woodworkers reporting exposure to formaldehyde (RR = 1.95, 95% CI = 0.63–6.06), but men not reporting exposure to these substances also had an excess risk. Although limited by a short follow-up period and crude indicators of exposure, the strengths of this analysis were the ability to compare woodworkers to a similar, healthy population and to adjust for the effects of smoking. Cohort studies with better exposure information are needed to examine the role of occupational exposures among woodworkers in the etiology of respiratory disease. Am. J. Ind. Med. 34:238–243, 1998. © 1998 Wiley-Liss, Inc.     

Cancer mortality among workers exposed to formaldehyde

Proportionate mortality among workers exposed to formaldehyde was analyzed among employees of a large chemical plant in Western Massachusetts. Twenty-four such decedents, all males, were identified through union records, reports of former coworkers, and a systematic review of obituaries in local newspapers. Work histories were obtained from seniority lists. Race-age-sex-adjusted proportionate mortality ratios (PMRs) were significantly elevated for cancer of the colon based on United States. county, and county cancer mortality proportions (PMR = 702, 424, 333, p ≤ 0.05). as were PMRs for the category buccal and pharyngeal cancer (PMR = 870, 952, 833. p < 0.05). This study provides evidence of formaldehyde's carcinogenicity. These findings are at variance with a previous report of the mortality experience of workers at the same plant from an earlier period.     

Cancer mortality among Danish molders

This study was set up to investigate potential chronic health effects associated with molding in the foundry industry. For this purpose, a cohort of 632 male molders was followed through 10 years with regard to cause-specific mortality. Comparisons were made with another cohort of skilled workers. The mortality from cancer was increased among the molders (standardized mortality ratio 152, 95% confidence interval 100-221), mainly because of an excess number of deaths from bladder cancer (standardized mortality ratio 896, 95% confidence interval 329-1,949). It is suggested that certain mold types may emit bladder carcinogens. In addition, phenols, cresols, and aldehydes in the foundry work atmosphere might act as tumor promoters.     

Cancer mortality among shoe and leather workers in Massachusetts

A proportional mortality analysis of death certificates of 2,798 shoe and leather workers demonstrated a statistically significant excess of bladder cancer among female shoe workers (PMR = 2.51, 95% confidence interval 1.23 to 5.12). A case-referent analysis of 289 leather workers, on whom detailed occupational information was available, demonstrated an association of lung cancer with work in leather-tanning jobs (odds ratio = 4.2, 95% confidence interval 1.09 to 16.2).     

Cancer mortality among northern Georgia carpet and textile workers

Proportionate cancer mortality was analyzed among white male carpet and textile workers in five northwest Georgia counties for the years 1970-1984. Compared with other Georgians, carpet and textile workers had higher proportions of lymphocytic leukemia (proportionate cancer mortality ratio [PCMR] = 2.9; 95% CI = 1.4-5.4]) and testicular cancer (PCMR = 3.2; 95% CI = 1.0-7.5). The excess mortality from lymphocytic leukemia was even higher when the analysis was limited to workers deemed most likely to work directly in production areas (PCMR = 4.2; 95% CI = 1.7-8.7). Further studies are needed to determine if the observed excesses are the result of workplace exposures.     

Cancer incidence and mortality among workers exposed to acrylonitrile

A cohort of 1,083 male employees who had potential for exposure to acrylonitrile between 1944 and 1970 at a Du Pont textile fibers plant were followed through 1981 for mortality and through 1983 for cancer incidence. In total, the 21 cancer deaths were fewer than expected based on either Du Pont or U.S. rates. No significant excesses were seen by primary site. In all, 37 cancer cases occurred as compared with 36.5 expected based on company rates. Five lung cancer cases were observed and 6.9 expected. There were 5 prostate cancer cases as compared with 1.9 expected. Of these, 4 occurred among wage employees during the 1975-1983 period, compared to 0.9 expected. This excess was statistically significant.     

Cancer mortality among chemical workers in an Italian plant

Objective of this study was to assess the mortality experience of a cohort of chemical workers at a plant located in central Italy. Subjects employed for any time between 1954 and 1970 at the chemical plant were included in the cohort and followed up to June 1991. The workers were classified as having ever/never worked in one of the following work processes: organic chemicals, acid mixtures, cleansing agents and insecticides. Mortality experience of the cohort was compared with that of the regional population by computing SMRs (standardized mortality ratios) and 90% CI (confidence intervals). Vital status was ascertained for 96% of the 505 cohort members. All causes of mortality for the entire cohort were lower than expected (Obs: 176; SMR: 0.90; 90% CI: 0.79–1.03). Analysis by work process revealed an increased mortality for lymphatic and hematopoietic tissue neoplasm in the cleansing agents department (Obs: 3; SMR: 5.00; 90% CI: 1.36–12.9); peritoneum and retropertioneum neoplasm in the organic compounds production (Obs: 2; SMR: 13.33; 90% CI: 2.37–42.0), and bladder cancer in the insecticides process (Obs: 3; SMR: 3.53; 90% CI: 0.96–9.12). Although the study had a low statistical power, the increased cancer risks detected are consistent with previous observations and may be of etiologic interest.     

Cancer mortality among French Atomic Energy Commission workers

BACKGROUND: All causes and cancer mortality of 58,320 workers employed at the Commissariat à l'Energie Atomique (CEA) between 1946 and 1994 were compared with that of the general population in a retrospective cohort study. METHODS: Standardized Mortality Ratios (SMR) were computed with reference to the French national population. RESULTS: Between 1968 and 1994, 4,809 deaths occurred. A healthy worker effect is observed for men (SMR = 0.57, CI(90%) = [0.56;0.59]) and for women (SMR = 0.72, CI(90%) = [0.67;0.77]). Nine sites of cancer death were found to be in statistically significant deficit among men, none among women. An excess of pleural cancers is observed among men (SMR = 1.79, CI(90%) = [1.27;2.45]) and of malignant melanoma (SMR = 1.50, CI(90%) = [1.04;2.11]). An excess of breast cancer is observed among women on the borderline of significance (SMR = 1.14, CI(90%) = [0.94;1.37]). CONCLUSIONS: Excesses observed will have to be related to occupational exposures in the on-going cohort study on French nuclear workers which includes a retrospective exposures assessment.     

Cancer mortality among jewelry workers

Mortality was investigated for the years 1950–1980 for 1,009 male members of a New York jewelry workers union, and for the years 1984–1989 among 919 men and 605 women identified as jewelry workers on death certificates from 24 states. Malignant neoplasms were excessive for male union members (proportional mortality ratio [PMR] = 1.17; 95% confidence interval [CI]: 1.02–1.33) and female jeweler deaths from the 24 states (PMR = 1.24; 95% CI: 1.07–1.42). Deaths due to nonmalignant causes were not unusual, except for excesses, in union males, of the circulatory system (PMR = 1.10; 95% CI: 1.02–1.19), including arteriosclerotic heart disease (PMR = 1.25; 95% CI: 1.14–1.37) and rheumatic heart disease (PMR = 3.02; 95% CI: 1.94–4.50). Cancers of the digestive tract were proportionally elevated among union males (proportional cancer mortality rate [PMR] = 1.13; 95% CI: 0.89–1.41) and among deaths from the 24 states (PCMR = 1.22; 95% CI: 1.01–1.47). For the 24 states, excesses for digestive cancer were found for both males (PCMR = 1.19; 95% CI: 0.90–1.54) and females (PCMR = 1.26; 95% CI: 0.96–1.62). Regarding specific sites in the digestive tract, colon cancer excesses were found in union males (PCMR = 1.53: 95% CI: 1.05–2.15), and for men (PCMR = 1.27; 95% CI: 0.82–1.88) and women (PCMR = 1.36; 95% CI: 0.92–3.27) in 24 states. Also, in the 24 states, excesses were noted for esophageal cancer (PMR = 2.03; 95% CI: 1.08–3.47) and stomach cancer (PCMR = 1.66; 95% CI: 0.95–2.69), due to excess stomach cancer in women (PCMR = 2.50; 95% CI: 1.20–4.61). Marginal proportional excesses were found for malignancies of the hematolymphopoietic system in union males (PCMR = 1.12; 95% CI: 0.72–1.67) and among deaths from 24 states (PCMR = 1.23; 95% CI: 0.90–1.66), particularly due to non-Hodgkin's lymphoma deaths (PCMR = 1.39; 95% CI: 0.93–2.00). The wide variety of exposures in this industry, particularly to metals and solvents, could possibly involve excess risk for malignancy at these sites. © 1993 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Cancer mortality among leather tanners

Workers were studied at a tannery that operated from 1873 to 1960, once one of the biggest in Scandinavia. The results show a slight numerical increase of deaths from cancer of the stomach and a significant, threefold excess mortality from cancer of the pancreas. Even in view of critical questions about validity it seems likely that this excess might be related to exposure to chemicals in tannery work.     

Cancer mortality and incidence among a cohort of benzidine and dichlorobenzidine dye manufacturing workers

BACKGROUND: Benzidine is classified as a definite human carcinogen and dichlorobenzidine as a probable human carcinogen. METHODS: A cohort study of 538 workers potentially exposed to benzidine and/or dichlorobenzidine from a single chemical manufacturing facility was conducted. Social Security records were used to identify all employees who worked at the facility from 1960 to 1977. Vital status was determined through 2001 and cancer incidence through 2002. RESULTS: A total of 22 bladder cancer cases were identified. For three individuals, bladder cancer was the underlying cause of death. Increased standardized mortality ratios (SMRs) were found for all cancer 1.54 (95% CI 1.04-2.19), bladder cancer 8.34 (95% CI 1.72-24.78), and lymphohematopoietic cancer 2.84 (95% CI 1.04-6.18). The standardized incidence ratio (SIR) for bladder cancer was 6.85 (95% CI 4.30-10.4). Only one case of bladder cancer was identified among the workers who were exposed to dichlorobenzidine only. However, an increased risk for lymphohematopoietic cancer was found among these dichlorobenzidine only workers (SMR 6.62 (95% CI 1.37-19.36)). CONCLUSIONS: This study confirms the high risk of bladder cancer among benzidine exposed workers even years after exposure has ceased, and raises suggestive evidence of increased risk to lymphohematopoietic cancer from exposure to benzidine or dichlorobenzidine.     

Cancer mortality among rice growers in Novara Province,Northern Italy

Some excess of non-Hodgkin lymphomas (NHL) and soft tissue sarcomas (STS) was reported in the literature among agricultural workers, mainly in relation to exposure to phenoxyacids and chlorophenols. In this study, information was analyzed for a cohort of rice growers that comprised 1,493 subjects, and for a follow-up that was more than 99% complete with regard to both traced subjects and known causes of deaths. A total of 960 subjects (65%) died during the observation period (1957–1992). Lower than expected standardized mortality ratios (SMRs) were found for all causes, for cardiovascular diseases (especially ischemic heart disease) and for all cancers. Slightly increased SMRs were found for some cancer sites (oral cavity, esophagus, liver, intestines, pancreas, bladder, STS, and NHL), although none of these was statistically significant in the overall analysis. An excess risk of close to statistical significance was found for NHL among workers with longer exposure during the period when phenoxyacid herbicide was in use (1950–1992). Thus, a prolonged follow-up is advisable. At present the study should be evaluated in the context of the data set suggesting a tendency toward an increased risk of NHL among farmers. Am. J. Ind. Med. 31:435–441, 1997. © 1997 Wiley-Liss, Inc.