Entwicklung der Ökotoxikologie von Pflanzenschutzmitteln in den letzten 25 Jahren: Von ersten Diskussionen über Prüforganismen zur probabilistischen Risikoanalyse

In Europe as well as in Germany a remarkable development within the last 25 years took place in the assessment of ecotoxicological effects of Plant Protection Products (PPPs). The starting point was a comparative, retrospective toxicity testing of some selected indicator species. Then, first attempts of a quantitative, prospective hazard and risk assessment with relevant exposure evaluations were made. Currently a probabilistic risk analysis on the landscape level is discussed.Based on personal experiences within the last decades this contribution will highlight the different developments of the ecotoxicological evaluation of PPPs. At first, the selection of suitable test species and the development of suitable standardized test methods was the main task. Thereafter, the discussions focused more on long-term, chronic effects instead of solely acute ones, the development of focused higher tier studies adjusted to better address the specific properties of a PPP and/or the specific concerns resulting from its application, as well as multi-species and ecosystem approaches. With the availability of suitable computer based models a more precise exposure calculation was possible, which allows a more realistic exposure assessment instead of simple worstcase assumptions. Current discussions focus on probabilistic exposure assessments at a local scale.All these developments took place regardless of the insufficient (political) definition of the protection goal and — as a consequence — the need and extent of appropriate safety factors. The development of ecotoxicology was mostly driven by political trends in Europe, mainly by the harmonized registration of PPPs under the still valid Annexes II and III (1996) of the EU Directive 91/414 and the thereby initiated further progression. In the context of this development more and more scientists were offered interesting job opportunities.