Modelling human skin morphology and simulating transdermal transport of 50 chemicals

A mathematical model was developed to investigate the transdermal transport of 50 chemicals across human skin. The model incorporates key skin properties and physicochemical parameters. Simulations were performed using experimentally determined partition and diffusion coefficients for the different skin layers (Ellison et al., 2020). The simulation results were compared with experimental data for 13 chemicals. The predicted uptake dynamics were compared with temporal trends reported in experimental studies (Coderch et al., 2021; Hewitt et al., 2020; Deacon et al., 2024). A clear log P-dependent uptake behaviour was identified that enables a classification of the chemicals into three distinct groups. The simulation results demonstrate that the mesoscale diffusion model allows comparison of temporal uptake behaviour between chemicals.