Incidence of cancer among welders, platers, machinists, and pipe fitters in shipyards and machine shops.

Abstract

The incidence of cancer in 12 693 shipyard and machine shop male workers (1689 welders, 4308 platers, 6003 machinists, 693 pipe fitters) employed for at least one year between 1945 and 1960 was investigated in a retrospective cohort study. The welders had welded only mild steel and had not been exposed to hexavalent chromium containing fume. The follow up was 99-7% complete and the total number of person-years was 304 682. The incidence of cancer in 1953-81 was ascertained through the Finnish Cancer Registry. The observed numbers of cases of cancer were compared with the expected numbers based on regional urban rates. The smoking habits of the cohort were surveyed with a postal questionnaire sent to a sample of 961 workers. The smoking habits of the cohorts were similar and smoking was not more common than among the general population. The total number of cases of cancer was 611 (exp 629) among the shipyard workers and 376 (exp 388) among the machine shop workers. The incidence of lung cancer was increased among the shipyard workers (obs 227, exp 192). This excess was observed in all the worker groups and was most evident for the pipe fitters and platers. Among the machine shop workers, the incidence of lung cancer was lower than expected with the exception of the welders who had a slightly raised risk of lung cancer (obs 14, exp 10). The incidence of laryngeal cancer was slightly raised among the shipyard workers (obs 24, exp 20) but not in the machine shop workers. No excess risk was observed among the welders.

Incidence of cancer among welders and other workers in a Norwegian shipyard.

“…The demonstration of an increased incidence of lung cancer in several occupational categories at the shipyard is in accordance with the results of other investigations (9,17,18,20,21). However, the results from these studies are inconsistent as to which occupational groups had an excess of asbestos-related cancers, probably due to diverse routines for asbestos handling or possibly to methodological shortcomings.…”

“…The magnitude of the excess was higher than that reported in some epidemiologic studies on shipyard employees (9,17,20), while other authors have demonstrated an approximately twofold risk of lung cancer for shipyard workers (19,21,22).…”

“…Several epidemiologic studies indicate that welders exhibit a higher incidence of lung cancer th an selected reference populations (1)(2)(3)(4)(5)(6)(7)(8)(9), while others ha ve not reproduced these find ings (10, II). Asbesto s and smoki ng have been possible confounders in most of the studies (12).…”

“…The welders were all shipyard workers who had mainly welded mild steel. The recognized excess of lung cancer in the shipbuilding industr y is generally att ribut ed to asbestos exposure (9,(17)(18)(19)(20)(21)(22). Hence it was con sidered important to include contemporary workers at the ship yard , not onl y for a po ssibilit y to study their incidence of cancer as such, but also to serve as internal reference groups for the welder s.…”

Update of a meta-analysis on lung cancer and welding

“…Due to the fact that five of these subcohorts (ie, Finland, France, Germany, Norway, Sweden) had been separately published or updated (26,(32)(33)(34)(35), the IARC study itself was excluded from the database of the metaanalysis. However, in order to avoid losing the information provided by the four other unpublished subcohorts (ie, Denmark, England, Italy, Scotland), we extracted the relevant data on these subcohorts from the IARC study report (30) and included them in the database.…”