Musk fragrances and environmental fate models - HHCB as an example for model refinements

Abstract

The theory of environmental fate and distribution models is briefly introduced. Afterwards, by means of the models laid down in the European Union System for the Evaluation of Substances (EUSES) and the Geography-referenced Regional Exposure Assessment Tool for European Rivers (GREAT-ER) environmental concentrations of the polycyclic musk fragrance HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-[g]-2-benzopyrane) were calculated for the aquatic environment. Starting with a generic standard region a spatial refinement was carried out for the German river Ruhr region. The refinement was realised in different scenarios by successively replacing EUSES default parameters with realistic regional values and then applying the selected region to GREAT-ER. The results were compared to monitoring data from the region of the German Federal State of North Rhine-Westphalia (river Ruhr). It was shown that both EUSES and GREAT-ER estimate the median of the measured values very well in every scenario. Spatial refinement leads to lower concentrations. Even underestimations are possible if realistic regional parameters are inserted and a ready biodegradability is assumed. Furthermore, assuming the same region, the predicted concentrations of EUSES and GREAT-ER do not differ by more than a factor of 5. In addition, GREAT-ER delivers realistic regional information with visualised concentration profiles and maps.