ABSTRACT
This work group report aims to provide an overview of extrapolation methods that can be used to assess ecotoxicological effects of time-variable exposures.
In the past, ecotoxicological studies on the effects of plant protection products were mostly conducted under (quasi) constant exposure conditions (e.g., semistatic tests) or pulsed exposure simulating drift entries (e.g., in mesocosm studies). Now, rened exposure models like FOCUS (Forum for the Co-ordination of Pesticide Fate Models and Their Use) Steps 3 or 4 simulations (FOCUS 2001, 2007a, 2007b) predict complex exposure scenarios due to the combination of variable drift, runoff, and drainage entries in different types of ecosystems (ditch, stream, pond). Thus, the question arises how the results of the typical standard and higher-tier tests can be used for risk assessment considering this diversity of possible exposure scenarios. Therefore, the objective of the ELINK work group for extrapolation methods was to identify and evaluate tools to extrapolate effects between exposure scenarios.
