Aquatische Mesokosmosversuche im Zulassungsverfahren für Pflanzenschutzmittel

This article deals with the question of how to consider data from aquatic mesocosm tests in the registration procedure of plant protection products. The legal framework is presented. This type of test must fulfill special methodological requirements in order to become a valuable tool for risk assessment. If this is the case, the data from mesocosm studies is more important than that from laboratory tests. Such studies must only be submitted if the risk assessment on the basis of standard laboratory tests indicate a risk for aquatic organisms.