Development of a Low-Level Continuous Smoke Exposure System

This project will lay the groundwork for important studies with relevance to FDA tobacco product regulation, including the FDA’s regulatory responsibility to consider effects of exposure to tobacco products on bystanders. We will do so by improving an existing cigarette smoke exposure system to produce sidestream smoke at stable levels approximating real-world secondhand smoke exposures. Most commercially available cigarette smoking systems generate relatively constant levels but are not designed to deliver smoke through the low range of levels typical of many every-day situations. We have used our current smoke exposure system, which delivers sidestream smoke at low levels but that decay over time, to study dosage effects of secondhand smoke exposure on the rat vascular system. However, the decay in smoke concentration during the exposure period limits the type of study that can be carried out. Improving our system to generate sidestream smoke at low but continuous stable levels will enable collection of better data to characterize the dose-response between smoke exposure and acute vascular effects, and will increase the range of realistic exposure conditions that can be modeled.  This project will last for one year and will involve an initial phase devoted to instrumentation and smoke particle concentration monitoring using standard Marlboro Red cigarettes, followed by a rat exposure phase involving 40 subjects.