Avermectin and milbemycin parasiticides have a high toxicity to non-target organisms, are often persistent and may have a potential to bioaccumulate. The present project contributes to filling gaps in the database for a complete environmental risk assessment of these parasiticides. In addition, risk management strategies for parasiticides used in pasture animals were discussed. For ivermectin and selamectin, log Pow values were derived. In studies with zebrafish, bioconcentration factors were determined for ivermectin and doramectin. The evaluated risk management strategies include sustainable approaches to control parasites and risk mitigation measures. Parasiticides are a central component of strategies to control parasites. Yet, their prudent use is generally recommended. Treatment frequencies should be reduced to the minimum required to sufficiently control parasitoses. Where indicated, selective or targeted selective treatments should be used instead of strategic treatments. Six risk mitigation measures were evaluated with regard to their efficacy to reduce the risk for dung or soil organisms, and their practicability. For most of these risk mitigation measures, data gaps were identified that have to be filled in order to sufficiently specify the measures and to fully evaluate their suitability and practicability. Since most of the risk mitigation measures have the potential to contribute to a reduction of the environment risk caused by avermectins and milbemycins, a further development / specification is recommended.
For further information, see the final report of the project:
Römbke, J., Duis, K., Egeler, P., Gilberg, D., Schuh, C., Herrchen, M., Hennecke, D., Hölzle, L.E., Heilmann-Thudium, B., Wohde, M., Wagner, J., Düring, R.-A. (2019). Comparison of the environmental properties of parasiticides and harmonisation of the basis for environmental assessment at the EU level. UBA-Texte 44/2019. [read more]