Cancer risk among glass factory workers: an excess of lung cancer?

A total of 3749 workers employed for at least three months in two Finnish glass factories (cohorts A and B) were followed up for cancer in 1953-86 through the Finnish Cancer Registry. In cohort A (1353 men, 1261 women), 106 primary cancers were diagnosed among men, and their standardised incidence ratio (SIR) for all cancers was 99. Among women the risk was low (65 cases, SIR 64). In cohort B (450 men, 685 women), the relative risk of cancer was close to unity for both men (57 cases) and women (75 cases). The risk of cancer was analysed by primary site, type of work, years since first exposure, and age at diagnosis. The only significantly increased risks were those of lung cancer among men (SIR 130, 95% CI 100-167, cohorts A and B combined), and skin cancer among glass blowers (SIR 625, 95% CI 129-1827). An increased risk of lung, stomach, and colon cancer as well as of brain tumours has been reported in previous studies. It is postulated that the excess risk of lung cancer, detected in this study, can also be accounted for by lifestyle, and not only by possible occupational exposures, because a similar excess risk of lung cancer has been found previously for all industrial workers in Finland. Although the risk of stomach cancer in this study was increased among glass blowers, it was not high in the largest groups of plain glass workers. The risks of tumours of the central nervous system and colon were not increased either.     

Cancer risk among glass factory workers: an excess of lung cancer?

A total of 3749 workers employed for at least three months in two Finnish glass factories (cohorts A and B) were followed up for cancer in 1953-86 through the Finnish Cancer Registry. In cohort A (1353 men, 1261 women), 106 primary cancers were diagnosed among men, and their standardised incidence ratio (SIR) for all cancers was 99. Among women the risk was low (65 cases, SIR 64). In cohort B (450 men, 685 women), the relative risk of cancer was close to unity for both men (57 cases) and women (75 cases). The risk of cancer was analysed by primary site, type of work, years since first exposure, and age at diagnosis. The only significantly increased risks were those of lung cancer among men (SIR 130, 95% CI 100-167, cohorts A and B combined), and skin cancer among glass blowers (SIR 625, 95% CI 129-1827). An increased risk of lung, stomach, and colon cancer as well as of brain tumours has been reported in previous studies. It is postulated that the excess risk of lung cancer, detected in this study, can also be accounted for by lifestyle, and not only by possible occupational exposures, because a similar excess risk of lung cancer has been found previously for all industrial workers in Finland. Although the risk of stomach cancer in this study was increased among glass blowers, it was not high in the largest groups of plain glass workers. The risks of tumours of the central nervous system and colon were not increased either.     

Cancer incidence among workers in the Norwegian ferroalloy industry.

The total mortality and the incidence of cancer was studied among a cohort of employees at the six oldest ferrosilicon and ferromanganese plants in Norway. The cohort consisted of 6494 men employed for more than 18 months before 1970 and has been followed up from 1953 to 1982. The standardised incidence ratio (SIR) for cancer (all sites) was 0.94. The observed number of cancers was as expected for lung cancer (SIR = 0.99) and for most of the other cancer sites studied. A statistically significant reduction of stomach cancer was found (SIR = 0.72). There was an increased incidence of lung cancer (SIR = 1.75) and cancer of the prostate (SIR = 1.56) in the workers at one ferrosilicon plant and of colonic cancer (SIR = 1.90) at another ferrosilicon plant.     

Cancer incidence among workers in the Norwegian ferroalloy industry

The total mortality and the incidence of cancer was studied among a cohort of employees at the six oldest ferrosilicon and ferromanganese plants in Norway. The cohort consisted of 6494 men employed for more than 18 months before 1970 and has been followed up from 1953 to 1982. The standardised incidence ratio (SIR) for cancer (all sites) was 0.94. The observed number of cancers was as expected for lung cancer (SIR = 0.99) and for most of the other cancer sites studied. A statistically significant reduction of stomach cancer was found (SIR = 0.72). There was an increased incidence of lung cancer (SIR = 1.75) and cancer of the prostate (SIR = 1.56) in the workers at one ferrosilicon plant and of colonic cancer (SIR = 1.90) at another ferrosilicon plant.     

Incidence of cancer among workers producing calcium carbide.

The overall mortality and the incidence of cancer have been studied among male employees at a plant producing calcium carbide. The cohort was defined as all men employed at the plant for at least 18 months in the period 1953 to 1970 and was classified according to 10 occupational categories. The 790 men have been observed from 1953 to 1983 and the incidence of cancer in the cohort has been compared with national incidence rates. A significant excess of colonic cancer (standardised incidence ratio, SIR = 2.09) and of prostatic cancer (SIR = 1.78) was found, and also a slight excess of lung cancer among furnace and maintenance workers (SIR = 1.56). The possible exposure of the workers to polycyclic aromatic hydrocarbons, asbestos, and cadmium is discussed.     

Incidence of cancer among workers producing calcium carbide

The overall mortality and the incidence of cancer have been studied among male employees at a plant producing calcium carbide. The cohort was defined as all men employed at the plant for at least 18 months in the period 1953 to 1970 and was classified according to 10 occupational categories. The 790 men have been observed from 1953 to 1983 and the incidence of cancer in the cohort has been compared with national incidence rates. A significant excess of colonic cancer (standardised incidence ratio, SIR = 2.09) and of prostatic cancer (SIR = 1.78) was found, and also a slight excess of lung cancer among furnace and maintenance workers (SIR = 1.56). The possible exposure of the workers to polycyclic aromatic hydrocarbons, asbestos, and cadmium is discussed.     

Mortality and cancer incidence among Lithuanian cement producing workers

Aims: To investigate mortality and cancer incidence of cement producing workers.

Methods: A total of 2498 cement workers who have been employed at Portland cement producing departments for at least one year from 1956 to 2000 were followed up from 1 January 1978 to 31 December 2000. The cohort contributed 43 490 person-years to the study. Standardised incidence ratios (SIR) and standardised mortality ratios (SMR) were calculated as ratios between observed and expected numbers of cancers and deaths. The expected numbers were based on sex specific incidence and mortality rates for the total Lithuanian population.

Results: Significantly increased SMRs were found for all malignant neoplasms (SMR 1.3, 95% CI 1.0 to 1.5) and for lung cancer (SMR 1.4, 95% CI 1.0 to 1.9) among male cement workers. SIR for all cancer sites was 1.2 (95% CI 1.0 to 1.4). Excess risk was found for cancer of the lung (SIR 1.5, 95% CI 1.1 to 2.1). The SIR for urinary bladder cancer was also increased (SIR 1.8, 95% CI 0.9 to 3.5). The overall cancer incidence was not increased among females (SIR 0.8, 95% CI 0.6 to 1.1). With increasing cumulated exposure to cement dust, there were indications of an increasing risk of lung and stomach cancers among males.

Conclusions: This study supported the hypothesis that exposure to cement dust may increase the lung and bladder cancer risk. A dose related risk was found for stomach cancer, but no support was found for an increased risk of colorectal cancer.

     

Risk of lung, larynx, pharynx and buccal cavity cancers among carbon electrode manufacturing workers

Among workers employed in factories producing carbon graphite products the risk of cancer due to exposure to polycyclic aromatic hydrocarbons was estimated. In one cohort (plant A), a cancer incidence study was carried out; the number of cases were not significantly increased for lung cancers [7 cases, standardized incidence ratio (SIR) 79] or for cancers of the upper respiratory and alimentary tract (10 cases, SIR 103). In another cohort (plant B), a mortality study was carried out; neither the mortality from lung cancer [13 deaths, standardized mortality ratio (SMR) 118] nor that from upper respiratory and alimentary tract cancers (10 deaths, SMR 125) was significantly higher than expected. Within each cohort, a case-referent study was carried out. In plant A the odds ratios were high but nonsignificant for lung cancers (odds ratio 3.42) and upper respiratory and alimentary tract cancers (odds ratio 2.19) and they showed a nonsignificant relationship with duration of exposure. In plant B, the odds ratios were low for every cancer site.     

Incidence of cancer among workers in a Norwegian nitrate fertiliser plant.

The incidence of cancer among 2023 male fertiliser workers has been investigated in a historical cohort study. Workers who had been employed for more than one year in work with possible exposure to dust containing nitrate between 1945 and 1979 were included. An individual cumulated exposure to dust expressed in level-years was calculated for each participant. The cohort was followed up from 1953 to the end of 1988, and the incidence of cancer was compared with the national rates. There were 467 deaths v 504.8 expected (standardised mortality ratio (SMR) = 0.93), and 185 cases of cancer v 195.5 expected (standardised incidence ratio (SIR) = 0.95). Thirty cases of lung cancer were found v 27.5 expected (SIR = 1.09). No overall excess of gastric cancer was found (15 cases v 17.0 expected; SIR = 0.89). No association was found between cumulated exposure to nitrate and gastric cancer, and there was no association between duration of employment or time since first employment and incidence of gastric cancer.     

Cancers in concrete workers: results of a cohort study of 33,668 workers

OBJECTIVES—To study cancer morbidity patterns in concrete workers.
METHODS—A cohort of 33 503 concrete workers was enrolled in the study from 1971-86. The average duration of follow up was 19.4 years (582 225 person-years). The workers' cancer morbidity was compared with the morbidity of the general population.
RESULTS—A total of 3572 incident cancers were observed. Significantly increased standardised incidence ratios (SIRs) were found for all malignant neoplasms (SIR 107; 95% confidence interval (95%CI) 103 to 110), cancer of the lip (SIR 179; 95%CI 134 to 234), cancer of the stomach (SIR 139; 95%CI 122 to 158), cancer of the lung (SIR 125; 95%CI 114 to 137), and cancer of the prostate (SIR 108; 95%CI 101 to 116). Reduced risk was found for cancer of the large intestine (SIR 80; 95%CI 69 to 93) and cancer of the testis (SIR 50; 95%CI 26 to 87). Smoking was more prevalent among the concrete workers than in the general population (50% v 35%).
CONCLUSION—The study has shown a slightly increased overall risk of cancer among concrete workers. The increased risk of lung cancer could entirely be due to differences in smoking habits between concrete workers and the general population. There is a possibility that the smoking also has contributed to the increased risks of stomach cancer and lip cancer, but occupational factors may have contributed to these cancer sites.


Keywords: occupational diseases; constructions workers; smoking     

Incidence of cancer among the participants of the Finnish Asbestos Screening Campaign

OBJECTIVES: Cancer risk has been estimated for asbestos production workers or other heavily exposed asbestos workers in numerous studies. The bulk of the asbestos epidemic results come, however, from past intermittent exposures during asbestos product use. This study concentrated on estimating the risk of cancer in such a population. METHODS: Altogether 23285 men and 930 women invited to a nationwide screening campaign for benign asbestos-related diseases in 1990-1992 were followed for cancer through the Finnish Cancer Register up to 1998. Standardized incidence ratios (SIR) were calculated in comparison with the total Finnish population. RESULTS: Altogether 1392 cases of cancer were found among the men. The risk was slightly, but significantly elevated for lung cancer [SIR 1.14, 95% confidence interval (95% CI) 1.01-1.26), mesothelioma (SIR 2.77, 95% CI 1.66-4.31), and prostate cancer (SIR 1.21, 95% CI 1.09-1.34). The risk of lung cancer was slightly higher among the invited nonparticipants (SIR 1.48, 95% CI 1.20-1.79) than among the participants (SIR 1.02, 95% CI 0.88-1.17). About 98% of the lung cancers occurred in current or ex-smokers. CONCLUSIONS: In a population of long-term construction workers, the risk of lung cancer and mesothelioma was increased, but considerably lower than among insulators, asbestos sprayers, or patients with asbestosis. As it was not possible to follow most of the invited nonparticipants in the original screening study, selection bias by smoking or other life-style factors possibly correlated to the individual's decision to participate in the health screening cannot be excluded.     

Study of cancer incidence among 8530 male workers in eight Norwegian plants producing ferrosilicon and silicon metal

OBJECTIVES: To examine the association between cancer incidence, in particular incidence of lung cancer, and duration of work among employees in eight Norwegian plants producing ferrosilicon and silicon metal. METHODS: Among men first employed during 1933-91 and with at least 6 months in these plants, the incident cases of cancer during 1953-91 were obtained from The Cancer Registry of Norway. The numbers of various cancers were compared with expected figures calculated from age and calendar time specific rates for Norwegian men during the same period. Internal comparisons of rates were performed with Poisson regression analysis. The final cohort comprised 8530 men. RESULTS: A total of 832 cases of cancer were observed against 786 expected (standardised incidence ratio (SIR) 1.06). Among the furnace workers an increased incidence of lung cancer (SIR 1.57) and testicular cancer (SIR 2.30) was found. Internal comparisons of rates by Poisson regression analysis among the rural furnace workers showed a positive trend between incidence of lung cancer and duration of work of 1.05 (95% confidence interval (95% CI) 1.00 to 1.10)/work-year. Excess cases of prostate and kidney cancer were found among blue collar non-furnace workers, in particular among the mechanics. CONCLUSION: The results suggest associations between furnace work and lung and testicular cancer, and between non-furnace work and prostate cancer.

 

     

Incidence of cancer among anthophyllite asbestos miners in Finland.

A cohort of 736 male and 167 female workers of two anthophyllite mines in Finland was followed up through the Finnish Cancer Registry for cancer in 1953-91. Compared with the total cancer incidence of the east Finnish population, the men had a raised risk of total cancer (standardised incidence ratio (SIR) 1.7; 95% confidence interval (95% CI) 1.4-1.9), mainly attributable to an excess in lung cancer (SIR 2.8; 95% CI 2.2-3.6). The risk of lung cancer was somewhat higher among workers classified as heavily exposed (SIR 3.2; 95% CI 2.4-4.1) than among those moderately exposed (SIR 2.3; 95% CI 1.5-3.6) and the risk increased with increasing smoking and with increasing time of work with exposure. There were four cases of mesothelioma v 0.1 expected, all in men who smoked and had had a long and heavy asbestos exposure. Among women, a non-significant excess in total cancer (SIR 1.5; 95% CI 0.9-2.4) was found in the subgroup with heavy exposure to asbestos. Anthophyllite asbestos seems to have high potency in the carcinogenesis of lung cancer and low potency in carcinogenesis of mesothelioma in comparison with the other types of asbestos.     

Lung cancer in asbestos cement workers in Denmark.

OBJECTIVES: To study the relative and absolute risks of main types of lung cancer in a cohort of asbestos cement workers from Denmark. METHOD: A cohort of 7887 men and 576 women employed between 1928 and 1984 was compiled from the personnel files of Danish Eternit Production. The cohort was followed up for deaths, emigrations, and incident cancer cases during the period 1943-90. The observed number of lung cancer cases in the cohort was compared with the expected number based on incidences for the Danish population. Internal comparison was made with Poisson modelling. RESULTS: A total of 226 lung cancer cases were observed (223 men and three women). The standardised incidence ratio (SIR) for all lung cancer among men was 1.7 (observed number 223, expected number 129.7, 95% confidence interval (95% CI) 1.5-2.0). The SIRs were raised for all main types of lung cancer; adenocarcinoma 2.6, squamous cell carcinoma 1.7, and anaplastic carcinoma 1.5. The higher SIR for adenocarcinomas was found particularly with a latency period of 25 years or more. Among the 93 excess lung cancer cases, 36 were squamous cell carcinomas and 32 were adenocarcinomas. CONCLUSION: Asbestos cement work is associated with an increased risk of lung cancer of all main types. During the first 25 years after the start of employment this excess risk is shared almost equally between the different histological types of lung cancer, but the risk of adenocarcinomas is clearly higher after this point.     

Risk of cancer among paper recycling workers.

OBJECTIVES: Studies in traditional paper mills have indicated an excess cancer risk, and mutagenic compounds have been identified in the industry. No studies have reported on risk of cancer in paper recycling. Therefore the cancer incidence in Danish paper recycling mills was investigated. METHODS: 5377 employees in five paper recycling plants were included in a historical cohort study. The workers had been employed in paper recycling in 1965-90, and the cohort was followed up until 31 December 1993. The expected number of cancer cases was calculated from national rates. RESULTS: There was significantly more pharyngeal cancer among male workers (seven observed (standardised incidence ratio (SIR) 3.33, 95% confidence interval (95% CI) 1.34 to 6.87)). There was slightly more lung cancer among male workers in production (39 observed, SIR 1.21, 95% CI 0.86 to 1.65). Risk of Hodgkin's disease was doubled in male production worker (four observed, SIR 1.90, 95% CI 0.51 to 4.85). CONCLUSIONS: The increased risk of pharyngeal cancer found in this study is interesting but may be influenced by confounders such as smoking and alcohol intake. This study also indicates an excess risk of Hodgkin's disease, which is in accordance with some studies in the traditional paper mills. As this is the first report on risk of cancer in paper recycling, further studies are needed.     

Mortality and cancer incidence in Swedish battery workers exposed to cadmium and nickel

OBJECTIVE: To follow up cancer incidence and mortality in a group of Swedish battery workers exposed to nickel hydroxide and cadmium oxide. METHODS: 869 workers, employed at least one year between the years 1940 and 1980 were followed up until 1992. Vital status and causes of death were obtained from the Swedish cause of death registry. Cancer morbidity was retrieved from the Swedish cancer registry. Regional reference rates were used to compute the expected numbers of deaths and cancers. RESULTS: Up to 31 December, 1992, a total of 315 deaths (292 in men and 23 in women) had occurred in the cohort. For men, the overall standardised mortality ratio (SMR) was 106 (95% confidence interval (95% CI) 93.7 to 118) and for women 83.8 (95% CI 53.1 to 126). The SMRs for total cancer mortality were 125 (95% CI 98.2 to 157) for men and 69.5 (95% CI 25.5 to 151) for women. The SMR for lung cancer in men was 176 (95% CI 101 to 287). No lung cancers were found among female workers. Up to 31 December, 1991, a total of 118 cancers had occurred in the cohort. A significantly increased standardised incidence ratio (SIR) was found for cancer of the nose and nasal sinuses in men, three cases v 0.36 expected, yielding an SIR of 832 (95% CI 172 to 2430). Applying a 10 year latency period in cohort members exposed to > or = 1000 micrograms cadmium/m3, the SIR was 1107 (95% CI 134 to 4000). Similarly, for cohort members exposed to 2000 micrograms nickel/m3, the SIR was 1080 (95% CI 131 to 3900). CONCLUSION: There was an increased overall risk for lung cancer, but no exposure-response relation between cumulative exposure to cadmium or nickel and risk of lung cancer. There was a highly significant increased risk of cancer of the nose and nasal sinuses, which may be caused by exposure to nickel or cadmium or a combination of both exposures.

 

     

Cancer in ex‐asbestos cement workers in Israel, 1953–1992

A cohort of 3,057 male workers employed in an asbestos‐cement plant using 90% chrysotile‐10% crocidolite, located in Northern Israel, was followed from 1953–1992 for incidence and mortality from cancer. In the years 1978–1992, the cohort had an elevated risk for all malignant neoplasms combined (n > 153, SIR > 117, ns), lung cancer (n > 28, SIR > 135, ns), mesothelioma (n > 21; SIR >5000, p > .0001), unspecified pleural cancer (n > 5; SIR > 278 , P > .0001), and liver cancer (n > 7, SIR 290, ns). Risks for colo‐rectal (n > 19; SIR > 79, ns), bladder (n = 12, SIR 69) and renal cancers (n > 5, SIR 104) were less than expected. Risk for mesothelioma showed a sharp risk gradient with duration of exposure, increasing from 1 per 625 for those employed less than 2 years to 1 per 4.5 workers employed over 30 years. The ratio of mesothelioma to excess lung cancer cases was 2.9 to 1, or 3.6 to 1, if pleural cases of unspecified origin were included; the pleura to peritoneum ratio of verified mesothelioma cases was 20 to 1. This atypically high ratio of mesothelioma to excess lung cancer cases is suggested to be the combined result of high past asbestos exposures in the workers and their low prior risk for lung cancer, and possibly, relatively early smoking cessation in relation to asbestos exposure. Am. J. Ind. Med. 35:1–8, 1999. © 1999 Wiley‐Liss, Inc.     

Mortality and cancer incidence in a cohort of meatworkers

Methods: In a retrospective cohort study, a list of members of a meatworkers union in Australia was matched with the national death and cancer registries. Standardised mortality ratios (SMR) and standardised incidence ratios (SIR) were calculated using Australian population rates. Exposure to animal viruses, animal blood, animal faeces, and plastic pyrolysis products was assigned according to job title. A nested case control analysis examined the risk of mortality and cancer incidence by each exposure.

Results: There were approximately 20 000 subjects available for analysis. Male workers had increased risk of mortality from all causes (SMR 116, 95% CI 105 to 128) and from injury (SMR 131, 95% CI 108 to 157). Risk of incident lung cancer in males was non-significantly increased (SIR 164, 95% CI 97 to 259) and males had a raised risk of head and neck cancer (SIR 188, 95% CI 103 to 315). There were no significant associations with specific exposures.

Conclusions: Compared to the general Australian population, meatworkers have increased risk of death from all causes, death from injury, and incident lung and head and neck cancer. Analysis by occupational exposures did not disclose any strong evidence of specific occupational risk factors, although this analysis was limited by small numbers of some outcomes and exposure assessment which was based on job titles only.

     

Cancer incidence among members of the Norwegian trade union of insulation workers

Insulation work has been described as an occupation with high exposure to asbestos. A cohort of members of the Norwegian Trade Union of Insulation Workers (n = 1116), hired between 1930 and 1975, was established. During 2002, the cohort was linked to the Cancer Registry of Norway. The standardized incidence ratio (SIR) of pleural mesothelioma was 12.9 (95% confidence interval [CI] = 6.0-24.6). Two cases with peritoneal mesotheliomas were found (SIR, 14.8; 95% CI = 1.8-53.4). The SIR of lung cancer was 3.0 (95% CI = 2.3-3.8). Four cases of lung cancer were observed among cork workers without any exposure to asbestos, but to cork dust and tar smoke (SIR, 5.3; 95% CI = 1.5-13.6). Our study showed a high risk of mesothelioma and an elevated risk of lung cancer among members of the Trade Union of Insulation Workers.     

Lung cancer and mesothelioma in the pleura and peritoneum among Swedish insulation workers

OBJECTIVES: To estimate the risk of cancer and death in Swedish insulation workers some years after their exposure to asbestos had stopped. One hypothesis was that the risk of lung cancer would tend to decrease some years after the exposure had ended. METHODS: In a cohort study the cancer morbidity and cause of death was investigated in 248 insulation workers and compared with the corresponding morbidity and mortality in the general population. Due to stringent regulations, exposure to asbestos of all types had almost ended in Sweden in the mid- 1970s. Through a questionnaire, surviving insulation workers were asked about their exposure to asbestos and their smoking habits. RESULTS: Between 1970 and 1994 there were 86 deaths compared with the 46.0 expected (standardised incidence ratio (SIR) 1.9; 95% confidence interval (95% CI) 1.5 to 2.3), the increase was mainly due to an increased cancer mortality. The morbidity was increased for lung cancer (11 cases v 2.5 expected (SIR 4.4; 95% CI 2.2 to 7.9)), peritoneal mesothelioma (seven cases; no expected incidence could be calculated as the occurrence is too rare in the general population), cancer in pancreas (five cases v 0.7 expected (SIR 7.1; 95% CI 2.3 to 16.7)). No cases of pleural mesothelioma were found. The risk of lung cancer did not tend to approach that of the general population after the exposure to asbestos decreased. CONCLUSIONS: In the 1980s and the early 1990s, Swedish insulation workers still have a highly increased risk of diseases related to asbestos. The attributable risk for death and cancer was about 50%. The study also confirms the previous finding that mesothelioma in insulation workers seems to be situated in the peritoneum more often than in the pleura.