Case Studies using the Probabilistic Aggregate Consumer Exposure Model (PACEM) for Cosmetics Ingredient Safety Assessment.

Case studies for cosmetic ingredients propyl paraben, salicylic acid, methyl salicylate, D5 and methylisothiazolinone have been used to assess the functionality and performance of the online webtool PACEM (Probabilistic Aggregate Consumer Exposure Model), which is free and publicly available. PACEM can be used by a consumer safety assessor to estimate consumer aggregate exposures (from cosmetic and household care products) to a single ingredient present in multiple product types, used simultaneously by a consumer in any one day. In this evaluation, only cosmetic product exposure assessment has been reviewed. The tool uses probabilistic mathematical modelling approaches, incorporating survey data on the habits and practices of product use from different European populations. The model is used by an exposure assessor to generate either a) an external exposure dose metric (mg/kg/day), b) an internal systemic exposure dose (SED) metric (mg/kg/day) or c) a dermal load (μg/cm²). The case studies performed, indicate that PACEM is a useful tool for the cosmetics safety assessor, and generates credible outputs for regulatory dossier submissions.