In this study, the author examined (a) levels of airborne pollutants from environmental tobacco smoke in 8 restaurants, and (b) changes in urinary cotinine and nicotine levels among 97 nonsmoking subjects (i.e., 40 restaurant employees, 37 patrons, and 20 referents). Airborne pollutant levels were significantly lower in the control environments than in the nonsmoking dining rooms in which smoking was not permitted, and the levels were significantly lower in the dining rooms in which smoking was not permitted than in the dining rooms in which smoking was permitted. Levels of urinary cotinine and nicotine increased among subjects in the dining rooms in which smoking was permitted, and the increase was significantly greater in employees than patrons. There was a significant positive correlation between levels of urinary nicotine increase and the levels of airborne nicotine and solanesol. The results of this study support the restriction of smoking to designated areas that have separate ventilation systems, or the prohibition of smoking in restaurants.