Pesticides can cause serious problems in freshwaters. Picture: pixabay.
Air drift, surface runoff, drainage and percolation deliver pesticides to lakes, rivers and ground water, where they can have multiple ecological consequences. „Pesticides used in agriculture and garden plots can seriously affect the structure, biodiversity and functional properties also of fresh waters“, concludes Mark Gessner, acting director of IGB and one of the authors of the paper.
According to the authors, environmental quality standards of pesticides are commonly exceeded in Europe. Residues are found in higher concentrations than exposure assessments had predicted. This includes substances that have not been used in Germany for a long time.
What is more, practitioners often use pesticide mixtures. Mixtures can exacerbate impacts on organisms and ecosystems particularly when they act synergistically, but to date Yet, mixture effects have been insufficiently studied. Similarly important, communities in natural ecosystems are characterized by many interdependencies and reciprocities of species. By disrupting species interactions, pesticides can also cause profound indirect impacts on communities and ecosystems. According to the Leopoldina expert group, these uncertainties entail risks that are not adequately taken into account at present.
„The complexity of interrelations and the persisting information deficit call for a whole-system view for proper risk assessment“, reasons Gessner. Therefore, a rethinking is needed, where „pesticide regulation and practical applications need to be adjusted to address effects beyond individual species.“
IGB's commitment to and participation in the Leopoldina position paper was a matter of course for Gessner: „Evidence-based consulting for policy makers and society is part of our work at IGB. It ensures that scientific results can have an actual impact in practice.“
The discussion paper can be downloaded in English and German on the Leopoldina Website.
