Lung cancer mortality in a cohort of English foundry workers

Risk of lung cancer among welders and flame cutters: A systematic review and meta-analysis of case controlled studies

OBJECTIVES

The process of flame-cutting and welding is believed to be highly hazardous for workers involved in related industries. The study aims to provide a comprehensive quantitative effect of the risk of lung cancer due to exposure to welding fumes.

METHODS

A systematic review was conducted to extract published estimates of Odd's Ratio (OR) of the association of lung cancer and exposure to welding fumes, till 2022. Studies were extracted from the PubMed and Cochrane database and Google Scholar. Studies from all parts of the world were considered. Through a meta-analysis conducted with random effects model, a forest plot was created, and publication bias was checked using a funnel plot.

RESULTS

The meta-analysis yielded an OR of 1.28 (95% CI 1.055-1.55), with a moderately high heterogeneity between the studies [I2=72%; T2=0.0524;Q=36.12(P<0.001)]. The sensitivity and influence analysis confirmed the absence of highly influential studies that may have led to potentially distorted outcomes. The funnel plot showed no evidence of publication bias among the studies included in this analysis.

CONCLUSION

As the association between lung cancer and occupational hazards from exposure to welding fumes is certain, there is a need to control and regulate industrial activities that involve welding and flame cutting. Already, restrictions on safe levels of fume in the workplace are in operation.

A Cohort Study of Workers Employed in a Refractory Brick Plant

A mortality study was carried out on a cohort of workers who were exposed to silica dust in a refractory brick plant. The cohort was divided into two groups: workers with and without silicosis, and their mortality was contrasted with the death rate of Genova from 1960 to 1979. Results show an increased risk for laryngeal tumors (3 obs., 0.44 exp., SMR = 682), nonmalignant respiratory disease (16 obs., 3.2 exp., SMR = 500), and cardiovascular diseases (19 obs., 11 exp., SMR = 173) among silicotics. The mortality rate for lung cancer showed an increase for the cohort of workers as a whole (11 obs., 6 exp., SMR = 183). The almost double overall mortality observed in silicotic subjects raises some doubts about the validity of other proportional mortality studies that showed no excesses for workers in these industries.

Assessment of dust exposure in a steel plant in the eastern coast of peninsular Malaysia

BACKGROUND

Steel manufacturing produces dust, fumes, and pollutant gases that may give adverse health effects to the respiratory function of workers. Improper occupational hygiene practice in the workplace will affect both workers wellbeing and productivity.

OBJECTIVE

To assess the level of particulate matter [(PM2.5, PM10, and Total Particulate Matter (TPM)], and trace metal dust concentrations in different sections of a steel plant and compare with the occupational exposure values.

METHODS

The work environmental parameters of the particulate matters were evaluated using Indoor Air Quality, while metal dust concentrations were measured using portable personal air sampler. A total of 184 personal samples were randomly collected from workers in three major sections; steel making plant, direct reduced plant, and support group. Trace metal dust concentrations were subjected to wet mineral acid mixture digestion and analysed by atomic absorption spectrophotometer (AAS).

RESULTS

The overall average PM2.5 concentration observed was varied according to the section: steel making plant was 0.18 mg/m3, direct reduced iron plant was 0.05 mg/m3, and support plant was 0.05 mg/m3. Average PM 10 concentration in steel making shop (SMS) plant, direct reduced (DR) plant, and support plant were 0.70 mg/m3, 0.84 mg/m3, and 0.58 mg/m3, respectively. The average TWA8 of trace metal dusts (cobalt and chromium) in all the sections exceeded 1 to 3 times the ACGIH prescribed values, OSHA PELs, NIOSH RELs as well as USECHH OSHA, whereas TWA8 concentration of nickel for each section did not exceed the occupational exposure values.

CONCLUSIONS

The average PM2.5, PM10 and TPM did not exceed the prescribed values, while average trace metal dust concentration TWA8 for cobalt and chromium in all plants exceeded occupational exposure prescribed values. However, the nickel found did not exceed the prescribed values in all the plants except for NIOSH RELs.

Health status of male steel workers at an electric arc furnace (EAF) in Trentino, Italy

Background

The aim of this retrospective cohort study was to determine if the workers of an Electric Arc Furnace (EAF), which recycles scrap, had higher mortality and morbidity due to possible exposure to pollutants at work. EAFs do not run on coke ovens. In EAFs 40 % of the particulate matter (PM) is made up of PM _2.5. The foundry dust contained iron, aluminum, zinc, manganese, lead, chromium, nickel, cadmium, mercury, arsenic, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls and dioxins.

Methods

Mortality study: a cohort of 331 exposed workers (6731 person-years) was studied from 19/03/1979 to 31/12/2009 (mean follow up 20.7 years). The group of exposed workers was compared to the general population and to a small control group of 32 workers from the same company.

Morbidity study: rates of exemption from health fee for the seven major diseases of 235 exposed workers were compared to the rates of exemption in the Province of Trento.

Results

Mortality study: an excess mortality was found in the exposed workers as compared to the general population (SMR 1.13; 95 % CI: 0.76–1.62; 29 deaths) and to the internal group (RR 2.34; 95 % CI: 0.39–95.7). The mortality rate was increased for all tumours (SMR 1.36; 95 % CI: 0.75–2.29; 14 cases), for lung cancer (SMR 3.35; 95 % CI 1.45–6.60; 8 cases), for ischemic heart disease (SMR 1.27; 95 % CI: 0.35–3.26; 4 cases), for chronic liver disease (SMR 1.16; 95 % CI: 0.14–4.20; 2 cases) and for injury and poisoning (SMR 1.32; 95 % CI: 0.48–2.88; 6 cases).

Morbidity study: there was a statistically significant increase of diabetes, rheumatoid arthritis, hypertension and cardiovascular diseases in exposed workers.

Conclusions

With the limitations of this relatively small cohort, we found a statistically significant increase of diabetes, cardiovascular diseases and deaths due to lung cancer in exposed workers. These findings cannot be explained by PAH exposure alone; metal particulates are the most important pollutants in the working area of EAFs. A reliable method for measuring metal PM in tissues is urgently needed for exposure assessment. This study underlines the necessity to maximize the standards of security toward foundry dusts/diffuse emission. Further studies on EAF’s are needed to confirm our findings and to increase statistical power.

Mortality of Iron-Steel Workers in Anshanl China: A Retrospective Cohort Study

Foundry workers have increased mortality and morbidity risks from numerous causes, including various cancers. A retrospective Chinese iron-steel cohort study was conducted to examine the mortality effects of exposure to foundry work. Standardized mortality ratios (SMRs) and standardized rate ratios (SRRs) were calculated to evaluate mortality risks among male workers with exposure to 15 hazardous factors, adjusting for confounders. During 14 years of follow-up, 13,363 of 121,846 male workers died. SMR analysis showed a healthy-worker effect in comparison with the general population. SRR analysis showed increased risks for all causes, all neoplasms, and others among the exposed workers compared with non-exposed blue-collar workers. Combined exposure to polycyclic aromatic hydrocarbons and two or more dusts increased the risks of lung cancer (SRR = 654; 95% CI: 113-3,780) and other malignancies. Foundry work has adverse health effects, including carcinogenic risks.

Exposure to welding fumes increases lung cancer risk among light smokers but not among heavy smokers: evidence from two case-control studies in Montreal

We investigated relationships between occupational exposure to gas and arc welding fumes and the risk of lung cancer among workers exposed to these agents throughout the spectrum of industries. Two population-based case-control studies were conducted in Montreal. Study I (1979-1986) included 857 cases and 1066 controls, and Study II (1996-2001) comprised 736 cases and 894 controls. Detailed job histories were obtained by interview and evaluated by an expert team of chemist-hygienists to estimate degree of exposure to approximately 300 substances for each job. Gas and arc welding fumes were among the agents evaluated. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) of lung cancer using logistic regression, adjusting for smoking history and other covariates. The two studies provided similar results, so a pooled analysis was conducted. Among all subjects, no significant association was found between lung cancer and gas welding fumes (OR = 1.1; 95% CI = 0.9-1.4) or arc welding fumes (OR = 1.0; 95% CI = 0.8-1.2). However, when restricting attention to light smokers, there was an increased risk of lung cancer in relation to gas welding fumes (OR = 2.9; 95% CI = 1.7-4.8) and arc welding fumes (OR = 2.3; 95% CI = 1.3-3.8), with even higher OR estimates among workers with the highest cumulative exposures. In conclusion, there was no detectable excess risk of lung cancer due to welding fumes among moderate to heavy smokers; but among light smokers we found an excess risk related to both types of welding fumes.

Assessment of fatigue among working people: a comparison of six questionnaires

AIMS

To compare the psychometric qualities of six fatigue questionnaires in a sample of working persons.

METHODS

Internal consistency and test-retest reliability, content validity, convergent validity, and the dimensionality of the fatigue instruments were explored.

RESULTS

All scales had a satisfactory internal consistency. Furthermore, based on factor analyses and Mokken scale analyses, all scales were unidimensional and appeared to measure an identical construct. The Fatigue Assessment Scale (FAS) had the highest factor loading on the one factor solution obtained in a factor analysis of the total scores of all scales.

CONCLUSIONS

All the questionnaires were unidimensional and had good reliability and validity. The FAS was the most promising fatigue measure.

Psychometric qualities of a brief self-rated fatigue measure: The Fatigue Assessment Scale

OBJECTIVE

The main aim of this study was to examine the dimensionality and psychometric qualities of a new 10-item fatigue measure, the Fatigue Assessment Scale (FAS).

METHODS

As part of a longitudinal study, the respondents, all workers with at least 20 working hours per week, completed the FAS, four related fatigue measures, a depression questionnaire, and an emotional stability scale.

RESULTS

The FAS had a high internal consistency. The pattern of correlations and factor analysis showed good convergent and divergent validity. The FAS correlated strongly with the other fatigue scales. In a factor analysis of the five fatigue questionnaires, the FAS had the highest factor loading on a clear one-factor solution. Moreover, factor analyses revealed that fatigue, on the one hand, and depression and emotional stability, on the other hand, are separate constructs. Finally, it was shown that 8 out of the 10 FAS items were unbiased concerning gender; two had a uniform bias.

CONCLUSIONS

The FAS represents a potentially valuable assessment instrument with promising internal consistency reliability and validity. Gender bias in the FAS does not have consequences for use of the FAS.

Mortality at an automotive engine foundry and machining complex

Mortality was analyzed for an automotive engine foundry and machining complex, with process exposures derived from department assignments. Logistic regression models of mortality odds ratios (ORs) were calculated for 2546 deaths, and numbers of work-related deaths were estimated. Lung cancer mortality in the foundry was increased where cleaning and finishing of castings was performed (OR, 1.7; 95% CI, 1.15 to 2.4 [at mean exposure duration of exposed cases]) and in care-making after 1967 (OR, 1.5; 95% CI, 1.11 to 2.0). Black workers had excess lung cancer mortality in machining heat-treat operations (OR, 2.5, 95% CI, 1.4 to 4.3) and excess nonmalignant respiratory disease mortality in molding (OR, 2.5; 95% CI, 1.16 to 5.5) and core-making (OR, 2.7; 95% CI, 1.25 to 5.8). Stomach cancer mortality was elevated among workers with metalworking fluid exposures in precision grinding (OR, 2.4; 95% CI, 1.14 to 5.1). Heart disease mortality was increased among all workers in molding (OR, 1.6; 95% CI, 1.09 to 2.3), as was stroke mortality among workers exposed to metalworking fluids (OR, 1.8; 95% CI, 1.22 to 2.7). Malignant and nonmalignant liver disease mortality was elevated in assembly/testing and precision grinding. In this modern foundry, 11% of deaths were estimated to be work-related despite it's being largely in regulatory compliance over its 40-year existence. Machining plant exposures accounted for 3% or more of deaths there.

Lung cancer risk in iron and steel foundry workers: a nested case control study in Asturias, Spain

BACKGROUND

Workers of iron and steel foundries have a high lung cancer risk but the findings on specific processes associated with this risk are inconsistent. We examined the risk of lung cancer among workers in the main industrial processes of a large iron and steel foundry in Asturias, Spain.

METHODS

We conducted a nested case-control study comprised of 144 male lung cancer cases and 558 controls, selected from a study base of about 24,400 workers employed in the industry between 1952 and 1995. Cases were identified through linkage of industry records with those of two cancer registries. Controls were selected through industry records using incidence density sampling, were matched to cases by age and date of birth and had to be alive and without lung cancer at the time of selection. Smoking history was obtained through company medical records. Unconditional logistic regression was applied and all ORs were adjusted for age and tobacco consumption.

RESULTS

Workers were, on an average, heavy smokers and a very strong relation was observed for smoking (OR for "ever smoker" = 32.4). Workers having ever been employed in the blast furnace had an excess lung cancer risk (OR = 2.55, 95% CI 1.25-5.21) compared to a reference group of workers not employed in metal producing departments. A similar excess was observed for workers having as their longest held job employment in the blast furnace. A two-fold risk was also observed for workers in the main foundry. For subgroups of workers, tobacco smoking appeared to be an important positive or negative confounder.

CONCLUSIONS

In this large Spanish foundry, a high risk was observed for workers employed in departments with high exposure to crystalline silica, PAHs, and various other carcinogenic chemicals. Although comparisons were made between workers of the same industry, smoking habits differed and adjustment by smoking modified considerably the risk estimates.

Mortality from injuries and other causes in a cohort of 21,800 Brazilian steel workers

OBJECTIVES

Injury is the leading cause of death in the male working population of Brazil. An important fraction of these deaths are work related. Very few cohort studies of steel workers, and none from developing countries, have reported on mortality from injuries. This paper analyses mortality from work and non-work related injuries among Brazilian steel workers.

METHODS

Deaths during employment from 1 January 1977 to 30 November 1992 were analysed in a cohort of 21,816 male steel workers. Mortality rates specific for age and calendar year among the workers were compared with those of the male population of the state where the plant is located. Work related injuries were analysed by comparing the mortality rates for different subgroups of the cohort.

RESULTS

The number of deaths (391) was less than half that expected based on death rates of the general population. Over 60% (242) of deaths were due to injuries. Mortality from most causes was substantially below that in the general population, but that from unintentional injury, was 50% above that of the general population. Standardised mortality ratios (SMRs) were highest for the youngest and the oldest employees and for labourers and clerical workers. Mortality from motor vehicle injury was twice that expected from population rates (SMR = 209, 95% confidence interval (95% CI) 176-244). There was a 67% fall in the age adjusted mortality from occupational injuries in the study period.

CONCLUSION

The healthy worker effect in this cohort was greater than that commonly found in studies of occupational groups in developed countries, probably because of a greater socioeconomic gap between employed and unemployed populations in Brazil, and unequal distribution of health care resources. Mortality was especially high for motor vehicle injuries. The fall in mortality from occupational injuries during the study period was probably due to improvement in safety standards, increased automation, and better medical care. There is a need to investigate risk factors for unintentional injuries among steel workers, especially those due to motor vehicle injuries. Prevention of occupational and nonoccupational injuries should be a main priority in Brazil.

[Mortality among steel workers of the Basque Country]

Most of mortality studies among steelworkers pointed out an increased frequency on cancer mortality, above all by lung cancer, and, in a lower proportion, by cancers of digestive and genitourinary systems. In Spain mortality rates are not published by occupation and economic activity to contrast these observations. It was carried out a proportionate mortality study among active or retired workers from an steel mill, Altos Hornos de Vizcaya, died from 1986 to 1993, to make a preliminary death risk assessment associated with job in the steel industry. A sample of 1553 men was drawn from the mortality register of a private Insurance Company. Death causes within the sample and in general population of the Autonomous Community of the Basque Country were compared using a proportionate analysis. Mortality odds ratios (OR) were also computed. The results show an excess of cancer mortality (OR = 1.26, IC: 1.11-1.42), stomach cancer (OR = 1.50, IC: 1.14-1.98) and renal cancer (OR = 1.89; IC: 1.14-3.14) as it has been stated by other authors. It has not been found an increased mortality risk from lung cancer (OR = 1.13, IC: 0.91-1.40), bladder cancer (OR = 1.13, IC: 0.74-1.72) and chronic respiratory disease (OR = 0.94, IC: 0.73-1.20). There is also an excess of liver cancer (OR = 1.56, IC: 1.06-2.28) and cancer of non specified location (OR = 1.85, IC: 1.45-2.36). This can be due to classification bias that affects the study. On the other hand, these and other selection bias, discussed in this paper, could underestimate the lung cancer mortality. We can not conclude that, among the workers of the study, the mortality from several kind of cancer is not associated to occupational exposure. Furthermore, this excess of stomach and kidney cancer mortality may lead us to pose the hypothesis of cause-effect relationship with some not well identified carcinogens present at the steel working place.

Cancer risk due to occupational exposure to polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) demonstrate carcinogenic activity in animal models. Although some epidemiologic studies have implicated PAHs as risk factors for human cancer, the evidence reported to date has not been consistent. The purpose of this report is to describe the associations between occupational exposure to PAHs in the workplace and each of 14 types of cancer. A population-based, case-control study was carried out in Montreal to investigate associations between a large variety of environmental and occupational exposures on the one hand, and several types of cancer on the other. A detailed job history was obtained from each subject along with information on a number of potential confounders. Each job history was reviewed by a team of experts, who used this information to construct a corresponding history of occupational exposures. Among the PAH exposures considered were benzo(a)pyrene (B(a)P) and five categories of PAHs defined on the basis of the source material, namely, wood, petroleum, coal, other sources, and any source. Altogether, 3,730 cancer patients and 533 population controls were interviewed and their job exposure histories coded. For each of 14 types of cancer analyzed, three control groups were available: other cancer patients, population controls, and the pooled set of cancer and population controls. The associations between 14 cancer types and 6 PAH exposures were analyzed using logistic regression methods. For most types of cancer evaluated, there was no evidence of excess risk due to PAHs at the levels encountered in the occupations in which PAH exposure has been prevalent in the Montreal area. For a few cancer sites--the esophagus, the pancreas, and the prostate gland--there were suggestions of excess risk; these observations are noteworthy hypotheses for further investigation. For lung cancer, there appeared to be an increased risk due to PAHs among nonsmokers and light smokers, but not among heavy smokers.

[The mortality of a retrospective cohort of workers in a Spanish iron and steel plant. The methodological problems in defining the cohort]

The work environment of an iron foundry involved a large number of exposures related to several health problems, mainly lung cancer. "Altos Hornos del Mediterráneo (AHM)" fron Sagunto is an iron industry that stopped its foundry plant production in 1984. The present paper shows the methodological problems merged during the reconstruction of AHM workers' cohort. From personnel files a male cohort was defined for 7,018 males who worked at least one year and started work between 1950 and 1970, following them through 1991. The cause of death was obtained from de Civil register, Life insurance and reference hospitals. By means of experts the work areas were rated in three exposure levels. 6% of cohort members were lost during the follow-up. 2786 deaths were reported and 88% causes of death were retrieved. The enterprise data files let us to reconstruct the cohort, but the availability of a National Death Index, as there is in other countries would have made easier the job and would have improved the data quality.

Exposure of iron foundry workers to polycyclic aromatic hydrocarbons: benzo(a)pyrene-albumin adducts and 1-hydroxypyrene as biomarkers for exposure

Exposure to polycyclic aromatic hydrocarbons (PAHs) in foundry workers has been evaluated by determination of benzo(a)pyrene-serum albumin adducts and urinary 1-hydroxypyrene. Benzo(a)pyrene binding to albumin and 1-hydroxypyrene were quantitatively measured by enzyme linked immunosorbent assay (ELISA) and reverse phase high performance liquid chromatography (HPLC), respectively. 70 male foundry workers and 68 matched controls were investigated. High and low exposure groups were defined from breathing zone hygienic samples, consisting of 16 PAH compounds in particulate and gaseous phase. Mean total PAH was 10.40 micrograms/m3 in the breathing zone, and mean dust adsorbed PAH was 0.15 microgram/m. All carcinogenic PAH was adsorbed to dust. Median benzo(a)pyrene-albumin adduct concentrations (10-90% percentiles) were similar in foundry workers (smokers 0.55 (0.27-1.00) and non-smokers 0.58 (0.17-1.15)) pmol/mg albumin and age matched controls (smokers 0.57 (0.16-1.45) and non-smokers 0.70 (0.19-1.55) pmol/mg albumin). Median 1-hydroxypyrene concentrations were significantly higher (P < 0.0001) in smoking and non-smoking foundry workers (0.022 (0.006-0.075) and 0.027 (0.006-0.164)) mumol/mol creatinine than in smoking and non-smoking controls (0 (0-0.022) and 0 (0-0.010) mumol/mol creatinine). Dose-response relations between total PAH, pyrene, carcinogenic PAHs, and 1-hydroxypyrene for smokers, and polycyclic aromatic hydrocarbons adsorbed to dust for non-smokers are suggested. Exposure to PAHs adsorbed to dust showed an additive effect. There was no correlation between the concentrations of 1-hydroxypyrene and benzo(a)pyrene-albumin adducts. The change in 1-hydroxypyrene over a weekend was also studied. Friday morning median 1-hydroxypyrene concentrations were significantly higher in both smokers and non-smokers (0.021 (0-0.075) and 0.027 (0.06-0.164)) mumol/mol creatinine than Monday morning median concentrations (0.007 (0-0.021) and 0.008 (0-0.021) mumol/mol creatinine). Smoking did not affect the concentrations of 1-hydroxypyrene or benzo(a)pyrene-albumin adducts. These data suggest that 1-hydroxypyrene is a sensitive biomarker for low dose PAH exposure. Exposure to PAHs may be aetiologically related to increased risk of lung cancer in foundry workers.

Mortality among a cohort of United Kingdom steel foundry workers with special reference to cancers of the stomach and lung, 1946-90

OBJECTIVE

The aim was to describe cause specific mortality among steel foundry workers and to determine if any part of the experience may be due to occupation.

DESIGN

Historical prospective cohort study.

SETTING

Nine steel foundries in England and one in Scotland.

SUBJECTS

10,438 male production employees first employed in the period 1946-65 and with a minimum period of employment of one year.

MAIN OUTCOME MEASURES

Observed and expected numbers of deaths for the period 1946-90.

RESULTS

Compared with the general population of England and Wales, standardised mortality ratios (SMRs) for all causes and all neoplasms were 115 (observed deaths (Obs) 3976) and 119 (Obs 1129) respectively. Statistically significant excesses were found for cancer of the stomach (Obs 124, expected deaths (Exp) 92.5, SMR 134, 95% confidence interval (95% CI) 111-160) and cancer of the lung (Obs 551, Exp 378.3, SMR 146, 95% CI 134-158). A raised SMR (153) was also found for non-malignant diseases of the respiratory system. Classifications of jobs attracting either higher dust or higher fume exposures did not usefully predict these increased SMRs. Poisson regression was used to investigate risks of mortality from all cancers, cancer of the stomach, cancer of the lung, and non-malignant diseases of the respiratory system associated with duration of employment in the foundry area, the fettling shop, the foundry area/fettling shop, and the industry in general. Monotonic dose-response relations were not found, although there were positive trends for lung cancer and employment in the foundry area/fettling shop (1.0, 1.21, 1.44, 1.26) and for diseases of the respiratory system and employment in the fettling shop (1.0, 1.37, 1.18, 1.35).

CONCLUSIONS

Confident interpretation of the causes of the raised SMRs was not possible. There was limited evidence of an occupational role in the excesses of lung cancer and diseases of the respiratory system. Smoking history was shown, in an indirect way, to be an unlikely explanation.

Retrospective follow-up study of foundry and engine plant workers

A retrospective follow-up study of 21,013 workers employed at a foundry and two engine manufacturing plants was conducted to determine if these workers had an unusual mortality experience. A total of 2,235 deaths occurred during the follow-up period of 1970-1987. Mortality from all causes was lower than expected. Men experienced a 6-13% excess of lung cancer deaths, depending on the choice of the comparison group. The data displayed evidence of a positive trend between lung cancer mortality and increasing duration of employment (p = 0.008). White men experienced a statistically significant excess of deaths from stomach cancer (standardized mortality ratio [SMR] = 158; 95% confidence interval [CI] = 101-234). Black men had increased mortality from pancreatic cancer, especially among engine plant workers (SMR = 303; CI = 121-624), and an excess of prostate cancer, concentrated among foundry workers (SMR = 234; CI = 112-430).

Interaction of smoking, uptake of polycyclic aromatic hydrocarbons, and cytochrome P450IA2 activity among foundry workers

An increased lung cancer risk has been described among foundry workers. Polycyclic aromatic hydrocarbons (PAHs) and silica are possible aetiological factors. This study describes a urinary PAH metabolite, 1-hydroxypyrene (hpU), as well as the degree of cytochrome P450IA2 activity/induction as reflected by the urinary caffeine ratio (IA2) in 45 foundry workers and 52 controls; IA2 was defined as the ratio of paraxanthine 7-demethylation products to a paraxanthine 8-hydroxylation product (1,7-dimethyluric acid). Mean exposure concentrations for foundry workers were defined by breathing zone hygienic samples (respirable dust 1.2 to 3.52 mg/m3 (93 samples)) and as total PAH (0.46 micrograms/m3) and pyrene concentrations (0.28 micrograms/m3) (six samples). Non-smoking controls and foundry workers had similar IA2 ratios (5.63, 95% confidence interval (95% CI) 4.56-6.70 and 4.40, 95% CI 3.56-5.24). The same was true for smoking controls and foundry workers (9.10, 95% CI 8.00-10.20 and 8.69, 95% CI 7.37-10.01). Both smoking groups had raised IA2 ratios compared with non-smokers (p less than 0.01). Non-smoking controls and foundry workers had similar hpU concentrations (0.16, 95% CI 0.10-0.22 and 0.11, 95% CI 0.09-0.13 mumol/mol creatinine). Smoking foundry workers had raised hpU concentrations (0.42, 95% CI 0.25-0.59) compared with smoking controls (0.26, 95% CI 0.18-0.34) (p less than 0.01). A small subgroup of smoking foundry workers with the highest exposures to both silica and PAH also had the highest hpU concentrations (0.70, 95% CI - 0.07-1.47 mumol/mol creatinine) (p less than 0.04). Increased hpU concentrations in smoking foundry workers suggest a more than additive effect from smoking and foundry exposures resulting in increased PAH uptake. Increased P450IA2 enzyme activity was only found in smokers and no additional effect of foundry exposures was seen. These data suggest that smoking as well as work related PAH exposure may be casually related to increased risk of lung cancer in foundry workers.

Cancer incidence among foundry workers in Denmark

Cancer incidence was studied among 6,144 male foundry workers who were invited to participate in either of two Danish national silicosis surveys conducted during 1967-1969 and 1972-1974. Cancer incidence was followed through to the end of 1985 by computerized linkage to the Danish Cancer Registry, and Standardized Morbidity Ratios (SMRs) were calculated based on incidence rates for the Danish population. For the entire cohort, significantly elevated SMRs were seen for all cancers (SMR, 1.09; 95% CI, 1.01-1.18) and lung cancer (SMR, 1.30; 95% CI, 1.12-1.51), and SMRs were at the borderline of statistical significance for bladder cancer (SMR, 1.24; 95% CI, 0.97-1.59). Excess lung and bladder cancer risk were confined to workers who had worked in foundries for at least 20 y. There was a positive correlation between silicosis prevalence in employees at the foundries at the time of the x-ray examinations and lung cancer incidence during the follow-up period. Squamous cell carcinomas, anaplastic carcinomas, and other lung cancers accounted for the excess lung cancer risk, whereas there was not excess risk among the foundry workers for adenocarcinomas of the lung.

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.

Biological monitoring of foundry workers exposed to polycyclic aromatic hydrocarbons

This investigation describes benzo(a)pyrene (BP) serum protein adduct concentrations in 45 foundry workers and 45 matched non-occupationally exposed controls. High and low BP exposure groups were defined using breathing zone hygienic samples for both quartz and BP exposures. A newly developed enzyme linked immunosorbent assay detected benzo(a)pyrenediolepoxide-I binding to serum protein. Mean BP protein adduct concentrations (SD) for non-smoking (24.0 BP equivalents/100 micrograms protein (21.0] and smoking (28.0 (18.2] foundry workers were significantly higher than mean values for non-smoking (7.23 (8.72] and smoking (14.2 (24.4] controls. Foundry workers with high exposures to either quartz (28.4 (15.5] or BP (30.7 (19.3] had slightly raised mean adduct concentrations compared with foundry workers with low exposure for quartz (23.9 (23.1] or BP (24.5 (19.4). Highest mean adduct concentrations were found among a small group of workers with simultaneous high exposures to both quartz and BP (39.2 (6.5] suggesting an additive effect. These data support the ideas of a possible aetiological connection between an increased risk of lung cancer and BP exposure among foundry workers, and an additive effect between BP and quartz. Measurement of BP serum protein adduct concentrations appears to be a useful method by which groups exposed to BP may be biologically monitored.

Respiratory disease mortality patterns among South African iron moulders

To assess the influence of foundry exposure on malignant and non-malignant respiratory disease, the proportional mortality ratio (PMR) was used to compare the cause of death distributions of the 578 dead members of the Iron Moulders Society of South Africa, recipients of the union's death benefit fund between 1961 and 1983. Comparisons were made with the age and period specific white male deaths. For the 419 members where job information was available, the influence of occupation (journeyman, production moulder) was assessed using different techniques--the relative proportional mortality ratio (RPMR), the mortality odds ratio (MOR), and the proportional cancer mortality ratio (PCMR) for comparison. Excess PMRs were found for cancer of the trachea, bronchus, and lung (1.71, p = 0.03; Poisson one sided test) for those over 65 and for non-malignant respiratory disease (1.58, p = 0.01) and for injuries and poisonings (2.61, p less than 0.0001) in those under 65. Reduced PMRs were found for all cancers (0.75, p = 0.03) and all circulatory disease (0.91, p = 0.12) in those under 65. When comparing job types, raised risks were obtained for journeymen using all methods (RPMR, MOR, PCMR) but the small cell sizes rendered the results non-significant. The raised PMRs due to respiratory disease are unlikely to be due to smoking because of a poor association with other causes of death related to smoking. A more likely explanation is that these excess rates for malignant and non-malignant respiratory disease are due to exposure to the foundry environment. Of additional concern are the high PMRs due to injuries and poisonings, which could be related to the high accident rates in the iron and steel industry.

Cancer mortality in a cohort of United Kingdom steel foundry workers: 1946-85

The mortality experienced by a cohort of 10,491 United Kingdom steel foundry workers during the period 1946-85 has been investigated. These workers were all male operatives first employed in any one of the 10 participating foundries in 1946-65; all had worked in the industry for a minimum period of one year. Compared with the general population of England and Wales, statistically significant excesses relating to cancer mortality were found for cancer of the stomach (E = 77.4, O = 106, SMR = 137) and cancer of the lung (E = 229.2, O = 441, SMR = 147). A statistically significant deficit was found for cancer of the brain (E = 19.4, O = 10, SMR = 51). Involvement of occupational exposures was assessed by the method of regression models and life tables (RMLT). This method was used to compare the duration of employment in the industry, in "dust exposed" jobs, in "fume exposed" jobs, in foundry area jobs, in fettling shop jobs, and in foundry area or fettling shop jobs, of those dying from cancers of the stomach and lung with those of all matching survivors. The RMLT analyses provided evidence of an occupational involvement in the risk of death from lung cancer from work in the foundry area or fettling shop, and weaker evidence of an occupational involvement in the risk of death from stomach cancer from work in the foundry area.

[Physical occupational activity and colonic carcinoma mortality in Swiss men 1979-1982]

Colorectal cancers are the second most frequent cause of cancer death among men. To our knowledge, approximately six studies have been able to show an inverse relationship between occupational physical activity and colon cancer mortality. Information drawn from the mortality statistics for the years 1979-1982 was used to study this hypothetical association among Swiss men aged 15-79. At-risk-populations were calculated based on 1980 national census data on occupation of all Swiss men. Estimates of occupational physical activity (OPA) were based on job titles of death certificates and were "blindly" classified into three groups of low, moderate and high OPA by three independent experts. Among the cohort of 1.86 million men, 1995 deaths of colon cancer and 1066 deaths of rectal cancer occurred during the four study years. The standardized mortality ratio showed a significant, graded and inverse relationship between OPA and mortality from colon cancer but not from rectal cancer. The estimated relative risk for colon cancer of the physically inactive, as compared to those active, was 1.3 to 1.4, slightly influenced by minor differences in the way of classification of OPA. For several reasons this estimate of excess risk is probably on the low side. The subgroup of men with jobs with very high OPA showed no further reduction in risk of colon cancer, which suggests that other etiologic factors, such as diet, may play an important role. As sedentary lifestyle and colon cancer are both frequent in central Europe the hypothesized protective effect of habitual physical activity against colon cancer would seem important, especially from the public health point of view.

Gaseous and adsorbed PAH in an iron foundry

The increased risk of lung cancer among foundry workers is assumed to be associated with the inhalation of gaseous and particle bound polycyclic aromatic hydrocarbons (PAH). These compounds are produced during pyrolysis of carbon containing loading material in the moulding sand. The concentrations of 20 PAH, some of which are carcinogenic, have been determined in the dusty casting area of an iron foundry by means of gas chromatography and mass spectrometry. The total dust was fractionated by means of a precision cascade impactor. It was possible to differentiate the PAH load in microgram/mg dust in seven particle size fractions ranging from 0.36- greater than or equal to 24.95 microns. Initially, there was an increase of the adsorbed PAH mass concentration with increasing particle diameter up to a maximum of 1.1 microgram/mg in the dust of the 1.57 micron fraction. Thereafter there was a continuous decrease of PAH mass concentration with increasing particle size. When the differing weights of the seven fractions are taken into account, however, the total PAH load of the individual fractions increases steadily with increasing particle size. The inhalable fine dust, 31.4% of the total dust, contains 49.9% of the total adsorbed PAH. The gas phase contained on average three times more carcinogenic PAH with four and five rings than was adsorbed on the dust. Thus the percentage of the gaseous substances amounts to 77% of the total PAH load at the place of work in an iron foundry.

Mortality among ferrous foundry workers

Mortality analyses were carried out for 278 male hourly workers who were employed for at least 10 years at a gray iron foundry and who died between January 1, 1970 and December 31, 1981. Statistically significant excess proportional mortality due to non-malignant respiratory disease (SPMR = 177), lung cancer (SPMR = 148), and leukemia (SPMR = 284) was found among the 221 white males. Among nonwhite males there was a significant excess in proportional mortality due to circulatory diseases (SPMR = 143). White males in the Finishing classification experienced a significant excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 279) and lung cancer (SPMR = 179). White males in the Core Room classification experienced an excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 321). Case-control studies demonstrated a significant association between nonmalignant respiratory disease and the Finishing classification after controlling for the effects of age, prior occupations in coal mining or foundries, and smoking. A positive but nonsignificant association between lung cancer and Finishing was also found after controlling for age, prior work history, and smoking in case control studies.