[Mortality due to bronchopulmonary cancers in workers of 2 foundries]. / La mortalité par cancers broncho-pulmonaires parmi les salariés de deux usines sidérurgiques.

A mortality study was carried out in two factories producing stainless steel in order to assess lung cancer risk among workers employed in coke oven, blast and open hearth furnaces, foundry, electric furnace, hot and cold rolling mills and pickling areas. Occupational exposures of interest were chromium compounds, nickel compounds, polycyclic aromatic hydrocarbons (PAH), silica and asbestos. All male workers having at least one year of employment between 01.01.1960 and 31.12.1990 were followed up for mortality. The vital status was assessed from birth place registries. Complete job histories since date of first employment were abstracted from the company files. The smoking habits of 50% of the cohort members were known from medical records. The observed number of deaths (obs) were compared with the expected ones based on regional rates with adjustment for age, sex and calendar time (Standardized Mortality Ratio, SMR). The cohorts included 6324 (factory 1) and 5270 (factory 2) workers. The overall mortality did not differ markedly from that expected in both factories: SMR = 0.95 (obs = 1540, p = 0.05) in factory 1 and SMR = 1.06 (obs = 916, non-significant) in factory 2. SMRs for lung cancer did not differ from unity, respectively 0.99 (obs = 105) and 1.00 (obs = 54), in whole cohorts. Non-significant lung cancer excesses were observed among workers of some workshops where exposures of interest might have occurred: coke oven (SMR = 2.04), blast furnace (SMR = 1.36), open hearth furnace (SMR = 1.75), hot rolling mills (SMR = 1.29). These processes, however, are no longer involved in the study factories. Furthermore, no lung cancer excess was observed among workers employed in current workshops: electric furnaces and cold rolling mills.

Risk of lung cancer in workers producing stainless steel and metallic alloys.

OBJECTIVES: The mortality of workers involved in the production of stainless and alloyed steel from 1968 to 1992 was studied, in order to investigate the risk of lung cancer due to exposure to metals, i.e. iron oxides, chromium and/or nickel compounds. METHODS: The study design was a historical cohort mortality study and a nested case-control study concerning lung cancer. Standardized mortality ratios (SMRs) were computed using regional mortality rates as an external reference for comparing observed and expected numbers of deaths, adjusting for age, sex and calendar time. Conditional logistic regression was used to estimate odds ratios (ORs). Occupational exposure was assessed through the complete job histories of cases and controls and a specific job-exposure matrix. RESULTS: The cohort comprised 4,288 male and 609 female workers. The observed overall mortality was significantly lower than expected [649 deaths; SMR = 0.91; 95% confidence interval (CI) 0.84-0.98]. No significant SMR was observed for mortality from lung cancer (54 deaths; SMR = 1.19; CI 0.88-1.55). The case-control study was based on 54 cases and 162 individually matched controls. Smoking habits were available for 71%. No lung cancer excess was observed for exposure to (1) metals and/or their compounds, i.e. iron (OR = 0.94, CI 0.48-1.86), chromium and/or nickel (OR = 1.18, CI 0.62-2.25), and cobalt (OR =0.64, CI 0.33-1.25), (2) acid mists (OR = 0.43, CI 0.17-1.10), and (3) asbestos (OR = 1.00, CI 0.54-1.86). With respect to exposure to polycyclic aromatic hydrocarbons (PAHs) and silica, which are often found together in workplaces, (1) high and statistically significant lung cancer excesses were observed, the ORs being 1.95 (CI 1.03-3.72) and 2.47 (CI 1.28-4.77) respectively, (2) quantitative exposure parameters revealed upward trends reaching statistical significance (P < 0.05), and (3) adjustments for tobacco consumption did not reveal any confounding factors from smoking. CONCLUSION: This study failed to detect any relationship between lung cancer and exposure to iron, chromium, nickel and/or their compounds. High and statistically significant relative risks, along with increasing trends, were observed for simultaneous exposure to PAHs and silica.

Chromosome aberrations in peripheral blood lymphocytes of welders and characterization of their exposure by biological samples analysis.

Chromosomal aberrations in cultured lymphocytes obtained from 55 welders and 55 matched controls were analyzed. Depending on the welding techniques and the nature of the consumables and metals welded, three separate groups of welders were examined. Chromium, nickel, and manganese levels in serum and urine were measured to assess the exposure to welding fumes. A statistically significant increase of chromosomal aberrations was found in one of the three analyzed groups of welders. This group used the semi-automatic metal active gas welding process with cored wire containing nickel for welding mild steel. These welders had significantly higher concentrations of serum and urine manganese and, unlike the other welders, significantly elevated concentrations of nickel, both in serum and urine. However, no significant correlations between nickel or manganese levels and the frequency of chromosomal aberrations were found. There was a significant correlation between the length of welding employment of these welders and the frequency of chromosomal breaks, although there was no significant correlation between age and the frequency of chromosomal aberrations. The other two groups of welders, for which the analyses of biologic fluids proved chromium and manganese exposure, had no statistically significant higher frequency of chromosomal aberrations. One of these groups used the manual metal arc welding process with coated electrodes for welding mainly mild steel and the other group used the tungsten inert gas welding process for welding stainless steel. A significant correlation between the daily amount of cigarettes smoked and the frequency of chromosomal breakages, in controls as in welders, was observed. The present data indicate that certain welding processes may generate fumes that seem to have a clastogenic activity.