How to Assess the Dermal Systemic Exposure to Compounds Present in a Cosmetic Product? Methodology

摘要

The European Regulation (EC) No 1223/2009 states that cosmetic products found on the European market have to be safe for consumer health. In order to perform a safety evaluation, it is crucial to possess accurate exposure data. Actually few informations are available concerning the concentration of ingredients contained in a finished product and their respective cutaneous absorption parameter: exposure to ingredients is calculated from finished product data by considering 100 % of absorption. The aim was to develop methods to assess the dermal systemic exposure to compounds found in a cosmetic product. Nail polish was used for example. Exposure was assessed with the Monte Carlo probabilistic method. Frequency and quantity data were respectively obtained by a web national enquiry (n=1512) and by laboratory tests with volunteers (n = 97) in order to assess external dermal exposure to finished product; A method was developed for estimating the percentage of ingredients commonly found in polish, in order to assess external exposure per ingredient. This method involved three major steps: (ⅰ) elaboration of the list of ingredients commonly present in the cosmetic of interest; (ⅱ) determination of concentrations by weight of ingredients in the final product (using 34 patents and publications) and (ⅲ) concentration adjustments of ingredient concentrations under distribution form. An algebraic model to calculate systemic dermal exposure per ingredient in finite dose conditions was developed. This model was based on the use of substance permeability coefficient (Kp) with respect to the diffusion resistance induced by membrane thickness according to time. External exposure by nail and skin routes was evaluated for polish and for 23 compounds commonly found in it. Systemic exposure was assessed for 6 ingredients. Developed methods could be applied in exposure assessment and could allow a better safety assessment in case of cosmetic products.