Predicting Dermal Exposure to Semivolatile Organic Compounds Resulting from Direct Contact with Consumer Products

Dermal exposure through direct contact with consumer products is an important yet often overlooked pathway for human exposure to semivolatile organic compounds (SVOCs). In this study, a single-layer transient model was developed to improve our understanding of dermal exposure to SVOCs under direct contact scenarios. Using human skin equivalents combined with a Franz-type diffusion cell, an innovative experimental system was implemented to determine key model parameters, specifically skin diffusion and partitioning parameters (D_epi and K_epi/source), for 16 SVOCs across seven types of consumer products. The results demonstrate that using traditional permeability coefficients without considering the contact source can lead to inaccuracies in dermal exposure assessments. The model and measured parameters were validated against data from human subject studies, showing good agreement. Additionally, correlations between the key model parameters and the physicochemical properties of SVOCs were identified. Dermal exposure doses and associated health risks under various direct contact scenarios were assessed, with many cases showing hazard quotients near or above 1 and cancer risks exceeding 10^-4, highlighting its importance as a significant exposure pathway for SVOCs. This study provides valuable experimental and modeling tools for prioritizing SVOCs and guiding regulatory decisions on limiting their use in consumer products, thereby reducing potential health risks from dermal exposure.