We propose to develop coated porous media for human exposure assessment for airborne pollutants. After developing and validating extractable sorbent-coated foam as denuders for volatile and semi-volatile organic gases, the denuders will be incorporated into prototype multiple pollutant personal samplers (MPPS) for both gases and particles. The project builds on recent progress in personal sampling using activated carbon-impregnated open-cell foam. The first step involves creating an empirical model to predict the collection efficiency of coated foam. The model will be developed by measuring the SO2 collection efficiency of foam materials that have been coated with a weak base such as sodium bicarbonate. The results of chamber experiments with SO2 will be used to predict the diffusion of gas species into the porous structure. The resulting model will be used to design sampler components from extractable sorbent-coated foam, for collection of volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs). Design of modular multipollutant samplers will be guided by the results of chamber studies that measure organic gas capacity and particle penetration, using environmental tobacco smoke as a test aerosol. Such small (personal data assistant sized) personal samplers could simultaneously measure various workplace and home hazards, such as ozone, VOCs, SVOCs and particulate matter, in a way that minimizes sampling artifacts, at high sensitivity. In addition, this design may be scaled for indoor and outdoor area monitoring. ? ?
