Skip to main content
Ecotoxicological test development

More ecology in risk assessment

We are developing adapted ecotoxicological tests, taking into account sensitive species, to allow a more realistic environmental risk assessment.

More ecology in risk assessment

The requirements in ecological risk assessment require the use of ecosystem-relevant and vulnerable species and communities as well as the extension to chronic lethal and sublethal endpoints. In this context, we face the challenge of developing test systems in which natural species communities are represented or in which relevant endpoints (such as mortality, feeding rates, growth, reproduction) are reproducibly collected, and at the same time the test conditions are optimized to maintain a minimum stress level for the sensitive test organisms.

Single-species testing of aquatic invertebrates

Due to their sensitivity to pesticides, representatives of the EPT taxa (e.g. Cloeon dipterum, Rhithrogena semicolorata) and other species such as the phantom midge Chaoborus crystallinus and the amphipod Gammarus sp. are the subject of intensive research at gaiac. For these organisms, we investigate acute and chronic mortality as well as sublethal effects such as feeding inhibition and developmental delay.

In addition, we also offer complex test scenarios (e.g. Daphnia population tests with sediment) for standard species.

Test procedures for plankton and mesofauna communities

As a step between single-species laboratory tests and long-lasting, complex field experiments, we have developed test procedures for aquatic phyto- and zooplankton communities or terrestrial collembola/mite communities in recent years. These tests offer the possibility to investigate direct effects on a broader spectrum of species under more realistic conditions, and to analyse indirect effects by competition at the same time.

Up to


of species in streams are EPT taxa, but


standard test organism from this group is yet available

For the very diverse soiel mesofauna there are only


test species

Silke Classen

Phone: +49 241 – 8027640

Dr. Tido Strauss

Phone: +49 241 – 8027601

Taxonomic expertise

Good laboratory practice



seit 2008
Untersuchung des Einflusses von Pflanzenschutzmitteln auf Planktongemeinschaften in Indoor-Mikrokosmen unter konstanten Umweltbedingungen nach GLP | diverse Auftraggeber, 4 Studien, Stand 2021
Modelling approaches for a scenario based assessment of chemically induced impacts on aquatic macroinvertebrate communities | CEFIC, The European Chemical Industry Council
Nanomobil - Synthetische Silber-Nanopartikel im System Boden-Grundwasser: Mobilität, Wirkungen auf die Lebensgemeinschaft und Wechselwirkung zwischen Hydro-, Pedo- und Biosphäre. Teilprojekt AP 2 Biosphäre | BMBF, FKZ 03X0151A
Project website
Bewertung des Risikos für Bodenorganismen unter realen Bedingungen: Erarbeitung einer nationalen Position für die Ausgestaltung untergesetzlicher Regelwerke der neuen EU-Pflanzenschutzmittelverordnung | UBA, FKZ 3710 67 410
Project report
Verbundprojekt DanTox: Entwicklung und Anwendung eines Verfahrens zur Ermittlung spezifischer Toxizität und molekularer Wirkungsmechanismen sedimentgebundener Umweltschadstoffe mit dem Zebrabärbling (Danio rerio), Teilprojekt D: Statistische Auswertung | BMBF, FKZ 02WU1056

Publications & Presentations

Hammers-Wirtz, M., Gergs, K., Bruns, E., Classen, S. (2020): Cloeon dipterum - developing robust ecotoxicological test systems for mayflies. Poster presentation, SETAC SciCon 2020, SETAC Europe 30th Annual Meeting, 03-07 May 2020, Dublin, Ireland.
Strauss, T., Toschki, A.,Hammers-Wirtz, M. (2020): New approaches to testing acute toxic effects on natural plankton and soil communities. Poster presentation, SETAC SciCon 2020, SETAC Europe 30th Annual Meeting, 03-07 May, Dublin, Ireland.
Hammers-Wirtz, M., Classen, S., Strauss, T. (2019): Non-standard biotests – Intelligent testing to combine different needs and requirements for experimental and modelling approaches. Poster presentation, SETAC Europe 29th Annual Meeting, 26-30 May 2019, Helsinki, Finland.
Hammers-Wirtz, M., Strauss, T., Toschki, A. (2018): Added value of community approaches in environmental risk assessment. Poster presentation, SETAC Europe 28th Annual Meeting, 13-17 May 2018, Rome, Italy.
Strauss, T. (2018): Integration of temperature-dependent TKTD kinetics in individual-based population modelling – A case study with Chaoborus crystallinus. Platform presentation, SETAC Europe 28th Annual Meeting, 13-17 May 2018, Rome, Italy.
Toschki, A., Oellers, J., Willius, N., Hammers-Wirtz, M. (2017): A new screening approach for testing natural soil communities in the laboratory. Poster presentation, SETAC Europe 27th Annual Meeting, 07-11 May 2017, Brussels, Belgium.
Becker, D., Classen, S., Liedtjens, K., Preuss, T. G., Ratte, H. T. (2011): Ecotoxicological research in terms of sensitivity distinctions of lotic insect larvae with Imidacloprid. Poster presentation, SETAC Europe 21st Annual Meeting, 15-19 May 2011, Milan, Italy.
Hammers-Wirtz, M., Ratte, H. T. (2000): Offspring fitness in Daphnia: Is the Daphnia reproduction test appropriate for extrapolating effects on the population level? Environmental Toxicology and Chemistry 19 (7): 1856-1866. DOI: 10.1002/etc.5620190720.

We look forward to hearing from you!