A population-based case-control study was carried out to follow up obs
ervations of increased lung cancer risk in the steel pouring areas of
two Ontario steel mills. Study subjects were all men, aged 45-75 years
, who died of lung cancer in the cities of Hamilton or Sault Ste-Marie
, Ontario from 1979-1988. Nine hundred sixty-seven lung cancer victims
were matched with 2,827 control subjects who died of other causes. Wo
rk histories were provided by the employers of steelworkers. In compar
ison with other residents of their cities, the relative risk of death
from lung cancer was 0.85 (95% confidence interval [CI]: 0.58-1.23) fo
r steelworkers in Sault-Ste Marie and was 1.10 (95% CI: 0.89-1.37) for
steelworkers in Hamilton. In internal comparisons within the steel co
mpanies, increased lung cancer risk was observed among foundry, coke o
ven, and pouring pit workers. Retrospective hygiene assessment suggest
ed that the increased risk of lung cancer among steel pourers might be
related to the use of tar-based mold coating agents or to exposure to
mineral fibers. (C) 1994 Wiley-Liss, Inc.