Ten-year update on mortality among mild-steel welders.
OBJECTIVE
This study is an update on the lung cancer risk of mild-steel welders with no asbestos exposure using a cohort of nonwelders for comparison.


METHODS
The subjects came from three United States (US) plants that manufactured heavy equipment. The follow-up was extended from 1988 to 1998. The welders were not exposed to asbestos (typical of shipyard welders) or to chromium or nickel (present in stainless steel).


RESULTS
There were 108 lung cancer deaths among the welders and 128 such deaths among the nonwelders (double the previous number of lung cancer deaths). The standardized mortality ratio (SMR) for lung cancer was 1.46 [95% confidence interval (95% CI 1.20-1.76] for the welders and 1.18 (95% CI 0.98-1.40) for the nonwelders, both in comparison with the US general population. Direct comparison between the welders and nonwelders yielded a rate ratio of 1.22 (95% CI 0.93-1.59). Analyses using a 15-year lag time did not differ greatly from those of an unlagged analysis. There were no marked trends for lung cancer risk by duration of exposure or latency. Evidence from cross-sectional data from a sample of the cohort indicated that the welders smoked somewhat more than the US population and more than the nonwelders. An approximate adjustment of the rate ratios for possible confounding by smoking suggested that smoking may have accounted for about half of the excess lung cancer observed among the welders versus that of either reference population. CONCLUSIONS These data provide suggestive but not conclusive evidence of a modest lung cancer risk from mild-steel welding.
National Institute for Occupational Safety and Health, Cincinnati, Ohio, 45226, USA. nsteenland@cdc.gov
Kyle
K
Steenland
D000328:Adult; D017677:Age Distribution; D000368:Aged; D002318:Cardiovascular Diseases / Q000401:mortality; D016022:Case-Control Studies; D002423:Cause of Death; D015331:Cohort Studies; D006801:Humans; D008175:Lung Neoplasms / Q000209:etiology / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000401:mortality; D009784:Occupational Diseases / Q000401:mortality*; D016273:Occupational Exposure / Q000009:adverse effects / Q000706:statistics & numerical data; D016012:Poisson Distribution; D012016:Reference Values; D012140:Respiratory Tract Diseases / Q000401:mortality; D018570:Risk Assessment; D013232:Steel / Q000009:adverse effects*; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology; D014896:Welding / Q000706:statistics & numerical data*
D013232:Steel