This project will provide a short overview on existing methods for estimating aggregate consumer exposure, i.e. exposure that adds up from consuming different household consumer products, and is built upon the work that is already funded by LRI in response to the RfP B5 (call 2009). It will develop guidance on when to perform an aggregated exposure assessment and in two case studies show how consumer exposure from different sources can be evaluated. In addition, different tiers of exposure assessment are considered, ranging from deterministic screening methods to realistic evaluation of the distribution of aggregate exposure within a population. Finally, the different assessment tiers are related with different requirements concerning both available data and methodological approaches.
The two case studies will be performed with two different substances that will be determined based on input from an expert group and on the basis of key criteria proposed by the consortium. For the case studies, different exposure modelling tiers will be used.
For testing the tiered approach to estimating consumer exposure and for the analysis of key data gaps, comparison of the model results to experimental data is a prerequisite. For calculating realistic consumer exposure, in the case studies models will be used that rely on sensible mechanistic approaches. However, these models have not yet been systematically evaluated against experimental measurements (e.g. biomonitoring). Therefore, their ability to estimate realistic aggregate exposures should be validated. In order to critically evaluate the calculated exposure levels, for one substance biomonitoring will be performed under controlled experimental conditions and PBPK modelling will be used to compare biomonitoring to multi-source exposure calculations. In this process, the suitability of biomonitoring for aggregate exposure model validation will be assessed.
Bakker M., Biesterbos J.W.H., Bokkers B., Delmaar C., Dudzina T., Roeleveld N., Scheepers P.T.J., van Engelen J.G.M. and von Goetz N. (2014). Executive Summary "Estimation of realistic consumer exposure to substances from multiple sources and approaches to validation of exposure models" ,2.
Bakker M., Biesterbos J.W.H., Bokkers B., Delmaar C., Dudzina T., Roeleveld N., Scheepers P.T.J., van Engelen J.G.M. and von Goetz N. (2014). Final report "Estimation of realistic consumer exposure to substances from multiple sources and approaches to validation of exposure models" ,159.
Biesterbos J.W.H et all (2015). Aggregate dermal exposure to cyclic siloxanes in personal care products: Implication for risk assessment. Environment International. 74, 231-239.
Dudzina T., Delmaar C.J.E., Biesterbos J.W.H., Bakker M.I., Bokkers B.G.H., Scheepers P.T.J., van Engelen J.G.M., Hungerbuehler K. and von Goetz N. (2015). The probabilistic aggregate consumer exposure model (PACEM): Validation and comparison to a lower-tier assessment for the cyclic siloxane D5. Environment International. 79, 8-16. More supporting information can be found here.
Dudzina T., von Goetz N., Bogdal C., Biesterbos J.W.H. and Konrad H. (2014). Concentrations of cyclic volatile methylsiloxanes in European cosmetics and personal care products: Prerequisite for human and environmental exposure assessment. Environment International. 62, 86-94.
Biesterbos J.W.H., Dudzina T., Delmaar C.J.E., Bakker M.I., Russel F.G.M., von Goetz N., Scheepers P.T.J. and Roeleveld N. (2013). Usage patterns of personal care products: Important factors for exposure assessment. Food and Chemical Toxicology. 55, 8-17.
Usage patterns of personal care products: important factors for exposure assessment by Jacqueline W.H. Biesterbos, Tatsiana Dudzina, Christiaan J.E. Delmaar, Martine I. Bakker, Frans G.M. Russel, Natalie von Goetz, Paul T.J. Scheepers and Nel Roeleveld, presented at the 14th Cefic-LRI Annual Workshop
Aggregate consumer exposure to acrylic siloxane: worst case vs. probabilistic modeling by Tatsiana Dudzina, Natalie von Goetz, Jacqueline Biesterbos, Christiaan Delmaar and Konrad Hungerbühler, presented at the 14th Cefic-LRI Annual Workshop
Validation of a tiered approach to aggregate exposure modelling, by Natalie von Götz, presented at the 16th Cefic-LRI Annual Workshop 2014