Predicting Dermal Exposure to Gas-Phase Semivolatile Organic Compounds (SVOCs): A Further Study of SVOC Mass Transfer between Clothing and Skin Surface Lipids

Dermal exposure to indoor gas-phase semi-volatile organic compounds (SVOCs) has recently received a great deal of attention, and this has included evaluating the role of clothing in this process. Several models have been developed to assess dermal exposure to SVOCs, based on the transient mass transfer of SVOCs from air to dermal capillaries. Assumptions of these models are either that clothing completely retards SVOC transport, or that there is an air gap of constant thickness between the clothing and the surface of the skin, which may lead to errors in the model calculations. To solve this problem, we tried to describe SVOC transport between clothing and epidermis by considering two parallel processes: partitioning of SVOCs by direct contact (ignored in existing models), and Fickian diffusion through the air gap. Predictions from the present model agree well with the experimental data found in the literature (dermal uptake of diethyl phthalate (DEP) and di-n-butyl phthalate (DnBP) of a clothed participant). This study provides a useful tool to accurately assess dermal exposure to indoor SVOCs, especially for evaluating the effects of clothing on dermal exposure.