Improving emissions estimates of home and personal care products ingredients for use in EU risk assessments.

REACh introduces environmental release categories (ERCs) used to describe chemical emissions to the environment. These ERCs contain a number of default values that are combined with product usage data to estimate environmental exposure concentrations for use in risk assessment. The methodology presented in the present work constitutes a novel approach that allows for the coupling of population density and country-specific usage statistics for a range of home and personal care products. Spatially explicit usage estimates are presented for European Union (EU) hypothetical regions (200 × 200-km grid), as described in EU risk assessment frameworks. Recent sales and population density data are combined to assess the relevance of current default assumptions; that 10% of a product will be used in an EU hypothetical region that is inhabited by 20 million people. It is demonstrated that these assumptions are conservative and their relevance geographically limited. The highest usage estimates for hypothetical regions are located in southern England and a transboundary area in Europe consisting of Belgium, the Netherlands, and Germany. The maximum identified usage of 9 home and personal care product types, in an EU hypothetical region, ranges from 4.3% to 11.4%. The 99.5th percentile values, representative of an EU hypothetical region with a population of 20 million, range from 3.6% to 9.0%, which suggests that the current default parameterization of the ERCs may be overly protective for ingredients used in a number of home and personal care product types. Accordingly, it may be justified to use such an analysis to refine the default values in order to provide more realistic exposure estimates for use in REACh assessments.