Studies on Hazard and Risk Assessment

Higher tier aquatic risk assessment

Standard tests frequently represent an unrealistic exposure scenario. Especially for strongly adsorbable substances conditions in natural waters can be simulated more reality-like using tests performed in water/sediment systems. Moreover, standard tests usually refer to only one life stage, while natural populations consist of individuals in different development stages. Therefore, we offer tests that allow a more realistic exposure of the test organisms:

1. Tests in water - sediment systems or with pulsed exposure and recovery period (e.g. Daphnia and other invertebrates, Lemna and other macrophytes)
   
2. Expanded fish tests, e.g.:
   
   • Exposure of caged fish (e.g. rainbow trouts) in microcosms to assess survival and growth under exposure conditions close to reality  
     
   • Fish Early Life Stage tests with different species
   • In addition to Fish Full Life Cycle Tests with the zebrafish Danio rerio or Medaka we also conduct static flow-through tests in aquaria including sediment. Three different life stages are simultaneously exposed to realistic application patterns and monitored to the next generation.
3. Modified bioaccumulation studies with fish or invertebrates under realistic exposure in water/sediment systems.

Moreover, we conduct tests with non standard test species (algae, macrophytes, macroinvertebrates, fish) for probabilistic effect assessments using Species Sensitivity Distributions (SSD).

In this scope, we actually developed a new test design for chronic tests with lotic invertebrate species.

Refined effect assessment with model ecosystems - microcosms, mesocosms and TMEs

Tests with communities in semi-realistic environments build the highest tier in testing potential effects of plant protection products because they allow testing simultaneously effects on different species including indirect effects due to modified predator-prey or competition relationships. In addition, the recovery potential of affected species can be assessed.

Micro- und mesocosms are well-establised tools in aquatic ecotoxicology and often used for refined risk assessments of pesticides in order to reduce uncertainties in the extrapolation form laboratory standard tests to the situation in the field. In cooperation with gaiac - Research Institute for Ecosystem Analysis and Assessment - in Aachen, and the MESOCOSM GmbH in Homberg, the Fraunhofer IME is one of the international leading providers of such studies with 32 microcosm of 1 m³ at the Fraunhofer site in Schmallenberg, 30 artificial outdoor ponds of 5 m² at gaiac and 5 large artificial ponds to place up to 28 enclosures of 2 m² per pond at Mesocosm GmbH.

Until now, the Fraunhofer IME has conducted approx. 30 GLP- micro- or mesocsom studies.

In a similar way, we can offer studies conducted in Terrestrial Model Ecosystems (TMEs) to analyse effects of pesticides or other chemicals on soil invertebrates. These studies can be conducted in cooperation with gaiac in Schmallenberg or in Aachen. At the Fraunhofer site in Schmallenberg radiolabelled substances can be tested as well.