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Due to their low vapor pressure, semi-volatile organic compounds (SVOCs) can absorb onto other compartments in indoor environments, including settled dust. Incidental ingestion of settled dust-bound SVOCs contributes to the majority of daily non-dietary exposure to some SVOCs by human beings. With this pathway in mind, an integrated kinetic model to estimate indoor SVOC was developed to better predict the mass-fraction of SVOC associated with settled dust, which is important to accurately assess the non-dietary ingestion exposure to SVOC. In this integrated kinetic model, the aerosol dynamics were considered, including particle penetration, deposition and resuspension. The newly developed model was evaluated by comparing the predicted mass-fraction of SVOC associated with the settled dust ( X dust ) and the measured X dust from previous studies. Sixty X dust values of thirty-eight different SVOCs measured in residences located in seven countries from four continents were involved in the model evaluation. The X dust value predicted by the integrated kinetic model correlated linearly with the measured X dust : y = 0.93x + 0.09 ( R 2 = 0.73), which indicates that the predicted X dust by the integrated kinetic model are in good match with the measured data. This model may be utilized to predict SVOC concentrations in different indoor compartments, including dust-bound SVOC. [ABSTRACT FROM AUTHOR]

Abstract: Polycyclic aromatic hydrocarbons (PAHs) of outdoor origin can enter indoor environment via infiltration or ventilation, and lead to human exposure. This study presents a kinetic partition model for the prediction of indoor PAH concentrations that are of outdoor origin. The model was verified with the previous published measurement conducted in a chamber. Indoor gas-phase, particle-phase and airborne concentrations (the sum of the gas- and particle-phases concentrations) of 16 species of PAHs listed by United States Environmental Protection Agency (EPA) as priority pollutants were calculated over a two-year period by the kinetic partition model. The predicted concentrations were compared with those calculated using a simple linear instantaneous model. Uncertainty in the differences between the predicted results by these two models caused by uncertain parameters was further conducted. For some PAHs, remarkable differences existed between the predicted indoor gas- and particle-phases concentrations of outdoor originated PAHs by the kinetic partition model and by the linear instantaneous model. The average relative differences of gas-phase PAHs ranged from 3.60 × 10−6 to 6.31 × 101 while those of particle-phase PAHs were between 5.47 × 10−2 and 9.15 × 10−1. However, there was no obvious average relative difference between the predicted airborne concentrations, which maximized to 6.52 × 10−2. The average relative differences for both the gas- and particle-phases PAHs were even larger when particle deposition rate was at its maximum. [Copyright &y& Elsevier]