Understanding the relative importance of various exposure routes of aquatic organisms to hydrophobic chemicals, such as via the diet, is an area of growing interest as the regulatory arena expands to assess ecological risk based on the capacity for uptake and storage of chemicals from the environment.
Data interpretation of biomagnification factors (BMFs) is difficult, as dietary BMFs are not viewed as equivalent to field BMFs. This is based on the assumption that organisms have the potential to experience adverse perturbation through the uptake and storage of the chemical, which could lead to ecotoxicological effects at both the individual and population level, and in turn could cause unknown impacts on the food chain, for example due to reduced food for predators.
This information is most relevant for hydrophobic chemicals whereby assessing bioaccumulation is best achieved via dietary exposure bioaccumulation) tests. This project will thus help in the interpretation of dietary bioaccumulation tests in assessing B/vB properties, while providing an assessment of the environmental relevance that bioaccumulation may have on populations and ecosystems.
This project would aim at providing clear guidance on the use of dietary bioaccumulation tests through:
- Analysis of existing data from lab and field studies (both aquatic and terrestrial), and the subsequent use of the data to potentially determine mass balance / exposure pathways.
- When possible, analysis of results from lab studies according to the latest version of the OECD 305 guideline, deriving several endpoints like depuration rate constant, growth rate constant, kinetically-derived BMF…
- Development of a toxicokinetic modelling framework to improve the interpretation of dietary bioaccumulation.
- Use existing data and modelling output to evaluate the relevance of the assumption of adverse perturbations of highly hydrophobic substances regardless of trophic magnification.
Download here the full version of the RfP LRI-ECO33.