The impact of clean indoor air exemptions and preemption policies on the prevalence of a tobacco-specific lung carcinogen among nonsmoking bar and restaurant workers.

OBJECTIVES: We studied the impact of clean indoor air law exemptions and preemption policies on the prevalence of a tobacco-specific lung carcinogen-4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)--among nonsmoking bar and restaurant workers. METHODS: secondhand smoke were compared with results from participants who were exposed to it. RESULTS: Participants exposed to workplace secondhand smoke were more likely to have any detectable level of NNAL (P=.005) and higher mean levels of NNAL (P < .001) compared with nonexposed participants. Increased levels of NNAL were also associated with hours of a single workplace exposure (P=.005). CONCLUSIONS: Nonsmoking employees left unprotected from workplace secondhand smoke exposure had elevated levels of a tobacco-specific carcinogen in their bodies. All workers--including bar and restaurant workers--should be protected from indoor workplace exposure to cancer-causing secondhand smoke.