13th SETAC Scientific Symposium: Extrapolation of effects across biological levels

The 13th SETAC Scientific Symposium entitled ‘’Extrapolation of Effects Across Biological Levels: Challenges to Implement Scientific Approaches in Regulations’’ took place in Brussels on the 23rd and 24th of October. The symposium discussed extrapolation tools for environmental risk assessment purposes across different biological levels, and more importantly, how to bring those models to regulatory conformity. 

The existing applications and planned new approaches were reviewed in the context of the EU REACH, biocides, pesticides and pharmaceuticals legislations. The speakers presented the extrapolation methods involved in evaluating sub-individual to individual levels (AOPs, TK-TD), individual to population levels (ordinary differential equation models, AQUATOX, CASM) and population to landscape levels (Food-web, Ecosystem models). Finding the link between these approaches will be an important step forward in improving environmental risk assessment.

Extrapolation methods are one of the tools to reduce animal toxicity testing. Developments in mechanistic ecological models aim to replace the traditional approach of using safety factors and L(E)C50 values with models presenting more realistic scenarios. This type of model predictions will also help to better define uncertainties around risk. How to bring existing and newer models to the level of regulatory acceptance remains one of the critical questions. To this end, case studies were presented as one of the best ways to communicate scientific advances. Because of the growing regulatory needs and rapid scientific developments, more cross-disciplinary meetings on the topic will take place in the near future.

While a number of models have already been successfully applied to the aquatic environment, there is less interest given to models of terrestrial ecosystems. This subject will be one of the focuses for the next SETAC conference taking place in Helsinki in May 2019.