Evaluation of solanesol as a marker for environmental tobacco smoke in indoor environments

Solanesol has gained popularity as a marker for the particulate phase of Environmental Tobacco Smoke (ETS). It has been found to exist in fixed amounts with other ETS components in chamber and field studies. Apart from one study that examined the stability of solanesol under UV light, no other study has tested the robustness of solanesol under a variety of smoking and environmental conditions. This research fills that gap by evaluating the ratio of solanesol to nicotine, total and respirable suspended particulates, carbon monoxide and nitrogen dioxide under two laboratory conditions and a field setting.; Laboratory based experiments were carried out in experimental chambers. Cigarette smoke was generated using a novel laboratory-developed smoking machine designed to emit both mainstream and sidestream smoke. Particulates (and therein solanesol) was collected via active sampling and analyzed gravimetrically. Particulates were also measured using an optical sensor. Nicotine was collected and analyzed per NIOSH method 2551. Carbon monoxide and nitrogen dioxide were detected using real-time instruments.; In the first lab experiment, commercial cigarettes were smoked under current and proposed Federal Trade Commission (FTC) conditions. Results indicated that nicotine concentrations were significantly different when regular cigarettes were smoked under current and proposed conditions. The ratios of solanesol to all other ETS components were similar for both methods. The contribution of solanesol to particulate matter was between 1–3%. In the second laboratory experiment, cigarettes were smoked under different combinations of high and low temperatures and relative humidities. Except for nitrogen dioxide, all other ETS components registered a higher airborne concentration at high temperature and high humidity compared to low temperature and low humidity. The solanesol:RSP ratios ranged from to 0.56–1.57%, and most of the solanesol:nicotine ratios fell between 10–20%. In field studies the concentration of solanesol to TSP averaged 1–3%. This was similar to the ratio determined when cigarettes were smoked under the current and proposed FTC methods. The consistency of the ratio means that solanesol can be used to predict the concentrations of particulates arising from ETS in indoor environments.