ABSTRACT

The aquatic risk assessment procedure for pesticides under the Plant Protection Products Directive 91/414/EEC (EC, 1997) consists of 2 parts: 1) exposure assessment, which is the domain of environmental fate and behavior and exposure modeling, and 2) effects assessment, which is in the domain of ecotoxicology. Guidance on aquatic effects assessment for pesticides is provided in various workshop reports such as HARAP (Higher-Tier Aquatic Risk Assessment for Pesticides; Campbell et al. 1999), CLASSIC (Community-Level Aquatic System Studies-Interpretation Criteria; Giddings et al. 2002), EPiF (Effects of Pesticides in the Field; Liess et al. 2005), and AERA (Van den Brink, Maltby, et al. 2007), the SANCO (Santé de consommateurs) guidance document on aquatic ecotoxicology (EC 2002), and some recent opinions of the Scientic Panel on Plant Health, Plant Protection Products, and Their Residues (European Food Safety Authority [EFSA] 2005a, 2005b, 2006a, 2006b). Guidance on exposure assessments at the EU level became available in the

2.1 Introduction and Regulatory Background in Europe ..................................... 15 2.2 Introduction to the Decision Scheme for Aquatic Risk Assessment .............. 18

2.2.1 Regulatory Acceptable Concentration ................................................22 2.2.2 Time-Weighted Average Concentration Approach .............................23 2.2.3 How to Use the Decision Scheme .......................................................24