ABSTRACT
The characterization of risk to aquatic organisms is carried out by comparing effects endpoints of indicator aquatic species to exposure concentrations that might be expected in aquatic systems (both the water column and sediment). In the European Union, when carrying out these assessments for plant protection products, effects endpoints are divided by the exposure concentrations, which can be expressed as a “toxicity-exposure ratio” (TER). For the European Union, the guidance document that currently outlines the detail for this aquatic risk characterization is the aquatic guidance document SANCO/3268/2001 revision 4 (EC 2002). This document provides guidance on how to use the data provided to address the EU data requirements for the authorization of plant protection products to formulate a risk characterization or risk assessment. Supporting this guidance document are other guidance documents (Forum for the Co-ordination of Pesticide Fate Models and Their Use [FOCUS] 2001, 2007a, 2007b) and national guidance provided by member state regulatory authorities responsible for the registration of plant protection products. FOCUS guidance documents provide detailed procedures for calculating predicted environmental concentrations (PECs) of pesticides in water and sediment to which nontarget aquatic organisms may be exposed. The output of these calculations is a range of pesticide concentrations that vary both temporally and spatially as
3.1 Background .....................................................................................................25 3.2 Exposure Concentrations: Predicted Environmental Concentrations
in Surface Water and Sediment ......................................................................26 3.3 Acute (Short-Term) Risk Assessment .............................................................28 3.4 Chronic (Longer-Term) Risk Assessment .......................................................29
