Application of QSAR models to evaluate the dermal absorption of cosmetic ingredients.
Liu-F; Tu-V; Frederick-DM; Frasch-H
Toxicologist 2014 Mar; 138(1):414
Systemic exposure to cosmetic ingredients is an important factor to take into account during human health safety evaluation of cosmetic products. The information on dermal absorption is critical in order to accurately evaluate the systemic exposure. In vitro methods have been widely applied to determine the dermal absorption of cosmetic ingredients. Also, QSAR models have been proposed and utilized to predict the dermal absorption of chemicals based on their chemical properties. To evaluate the performance of various QSAR models to predict the dermal absorption of cosmetic ingredients, an in vitro dermal absorption study was conducted using a porcine (pig) skin model. Diglycerin is a common humectant used in cosmetic products and was used as a model ingredient in the current study. The dermal absorption profile over a 24-hour exposure period was measured and the kinetic data were fitted to various diffusion models and a combined diffusion/ binding model. The permeability coefficient (Kp) and lag time (t) were estimated with these models. The Kp value was compared with those predicted from publically available QSARs models. The maximum flux values (Jmax) were calculated from the kp values. Based on the Jmax values, default % dose absorbed (Kroes et al., 2007) through the skin per 24 hours ranged from 40% to 80%. The dermal absorption determined from the actual data is generally in agreement with the QSAR model prediction. The current study supports the use of QSAR models to predict dermal absorption for safety assessment of cosmetic ingredients. We suggest that multiple prediction models for dermal absorption should be applied in the absence of experimental data and that the most conservative prediction should be used in systemic exposure assessment of cosmetic ingredients.
Toxicology; Exposure-levels; Cosmetics-industry; Cosmetics; Cosmetics-workers; Skin-exposure; Skin-absorption; In-vitro-study; In-vitro-studies; Chemical-composition; Chemical-properties; Models
The Toxicologist. Society of Toxicology 53rd Annual Meeting and ToxExpo, March 23-27, 2014, Phonex, Arizona