Mortality from cancer and chronic respiratory diseases among workers who manufacture carbon electrodes

Abstract

Objectives-To investigate the risk of cancer and non-neoplastic respiratory diseases among workers who manufacture carbon electrodes, as this industry entails exposure to mixtures of polycyclic aromatic hydrocarbons. Methods-A historical cohort study was carried out of 1006 male workers employed for at least 1 year between 1945 and 1971 in a carbon (graphite) electrode production plant in central Italy, who were followed up for mortality between 1955 and 1996. The ratio of observed to expected deaths (standardised mortality ratios, SMRs) was computed from both national and (for the period 1964-96) regional age and period specific mortalities. A multivariate Poisson regression analysis was performed to investigate the relative risk (RR) of death according to duration of employment and time since first employment in the factory. Results-A total of 424 workers had died, 538 were still alive, and 44 were lost to follow up. Mortalities from all causes, all cancers, and respiratory tract cancer were in line with the regional figure. An excess was found over the expected deaths from skin cancer including melanoma (SMR 3.16, 95% confidence interval (95% CI) 0.65 to 9.23) and from non-neoplastic respiratory diseases (SMR 1.58, 95% CI 1.16 to 2.11). Poisson regression analysis including age as a covariate showed an increased risk of dying from gastric cancer with increasing duration of employment, and an increase in the RR of dying from lung cancer and from nonneoplastic respiratory diseases with increasing time since first employment, although the linear trend was not significant. Conclusion-This study supports previous findings that working in the carbon electrode manufacturing industry may not increase the risk of dying from respiratory cancer. However, a possible association with non-malignant respiratory diseases cannot be excluded. (Occup Environ Med 2000;57:484-487)

Occupational exposures to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx: a quantitative literature review

“…The three cohorts of carbon electrode workers (Donato et al 2000;Merlo et al 2004;Teta et al 1987) showed inconsistent results, with no observed deaths in one study (Teta et al 1987) and nonsignificantly increased risks in the two other studies (Donato et al 2000;Merlo et al 2004).…”

Cancer mortality among man-made graphite electrode manufacturing workers: results of a 38 year follow up

“…7 Thirty four lung cancer cases were observed, whereas 44.2 were expected (SMR 0.77; 95% CI: 0.53 to 1.08). Although they failed to identify a high risk group among the cohort because of lack of information on job title, they argued against lung cancer risk from graphite electrode manufacturing based on the negative relation between the duration of employment, a proxy for cumulative exposure to PAHs, and the relative risk for lung cancer.…”

“…[4][5][6][7] To evaluate their "population based corporate wide mortality surveillance system", Teta et al traced 2219 male workers for 10 years in several plants which manufactured graphite electrodes and other carbon products. 4 In their study, the SMR for respiratory cancers was 0.85 and no excess death was detected.…”

A mortality cohort study among workers in a graphite electrode production plant in Italy

“…These findings are partially in agreement with those from previous studies conducted in graphite electrode production workers in the USA, France, Sweden, and Japan, [1][2][3][4][5] and from an Italian study which revealed an excess of deaths for non-malignant respiratory diseases (SMR 1.58), but no excess of deaths for all cancers, lung or bladder cancers. 6 Since our study failed to detect a clear duration of employment-response relation for lung and bladder cancers, that are known to be linked to cigarette smoking habits and coal tar and coal tar pitch volatiles (that is, polycyclic aromatic hydrocarbons) in the workplace, we can conclude, with a good degree of confidence, against the possible role of these two factors in the observed excess mortality from all cancers. The discrepancies between our findings and those reported by other studies among carbon graphite workers, 1-5 may be also attributed to differences in the manufacturing process resulting in different exposure to toxic agents, including air levels of coal tar pitch volatile, PAH, and quartz.…”

“…[1][2][3][4][5][6] Their findings concerning overall mortality and mortality from specific causes, including respiratory diseases and site specific cancers, are conflicting and the scientific evidence of any health risk remains inconclusive. Occupational exposure to coal tar pitch, polycyclic aromatic hydrocarbons (PAH), and siliceous sands have been reported to occur during carbon and graphite electrode manufacturing.…”