Occupationally related risk of lung cancer among women and among nonsmokers has not been widely studied. A recently conducted population-based, case-control study in Missouri (United States) provided the opportunity to evaluate risk of lung cancer associated with several occupational factors. Incident cases (n = 429) were identified through the Missouri Cancer Registry for the period 1986 through 1991, and included 294 lifetime nonsmokers and 135 ex-smokers who had stopped at least 15 years prior to diagnosis or had smoked for less than one pack-year. Controls (n = 1,021) were selected through driver's license and Medicare files. Risk was elevated among women exposed to asbestos (ever: odds ratio [OR] = 3.5, 95 percent confidence interval [CI] = 1.2-10.0; > 9 yrs: OR = 4.6, CI = 1.1-19.2) and pesticides (ever: OR = 2.4, CI = 1.1-5.6; > 17.5 yrs: OR = 2.4, CI = 0.8-7.0). Risk also was elevated among dry cleaning workers (ever: OR = 1.8, CI = 1.1-3.0; > 1.125 yrs: OR = 2.9, CI = 1.5-5.4). Occupational risks for lung cancer among women merit further study.