Department Environmental Chemistry

Dynamic linkages between stressor concentrations and biological effects

Site-specific chemical and bioassay monitoring of micropollutants (MPs) are desirable, but the large number and diversity of MPs, and the cost and technical issues of measuring them, make the exposure assessment challenging. The use of water quality modeling techniques has been suggested as an alternative tool in situations where chemical and bioanalytical data are unavailable or are infeasible to implement.

In this project, we will first develop a site-specific environmental fate model to estimate the temporally and spatially varying concentrations of MPs. The estimates will then be fed into a toxicokinetic (TK) model that predicts the concentrations of chemicals in exposed organisms. The coupling of these two models can further elucidate the mechanistic linkages between fluctuating environmental exposure and the internal factors that affect the movement of chemicals to the target site of action (e.g., uptake and depuration). Eventually, the results of this work will be fed onto a toxicodynamic (TD) model that estimates the effects of chemical exposure across many levels of biological organization (e.g., organism, population). The model is currently being built mechanistically and employs extensive, field-derived datasets acquired from two successful projects (EcoImpact and Solutions) led by the Department of Environmental Chemistry at Eawag. Finally, this work is being completed using a multi-faceted approach that combines expertise in analytical chemistry, water quality modeling, and aquatic ecotoxicology.