Technical Report 123 PagesSUMMARY INTRODUCTION Terms of Reference Additional Considerations MEASURED PARTITIONING PROPERTY DATA Acid dissociation constant (Ka) Definition Ionisable groups Measurement Summary Partition coefficient (KOW) and distribution ratio (DOW) Definition Summary and recommendation Regulatory trigger values: Appropriateness, assumptions and gaps in science Adsorption-desorption distribution (Kd) and organic carbon-water partition (KOC) coefficients Definition Freundlich isotherms Summary and recommendation Regulatory trigger values: Appropriateness, assumptions and gaps in science Hydrolysis Biodegradation Definition(s) according to OECD Summary and recommendation Regulatory trigger values: Appropriateness, assumptions and gaps in science ESTIMATED PARTITIONING PROPERTY DATA Description of API dataset Computational methods log Kow pKa logDOW log KOC Biodegradation MULTIMEDIA MODELS TO DERIVE PEC USED FOR ERA OF IONISABLE ORGANICS Evaluative assessment of the equilibrium .chemical space’ for ionisable organic compounds Towards an improved regression for the sorption of ionisable organic compounds to sludge EXPERIENCES FROM THE AGROCHEMICALS INDUSTRY The concept of soil adsorption and desorption The synthetic pesticide .chemical space’ General trends in the soil availability of pesticides Soil adsorption and soil pH Soil adsorption and clay mineralogy Soil adsorption and the chemical nature of the soil organic matter Soil adsorption and metal chelation Conclusion REGULATORY IMPLICATIONS AND RECOMMENDATIONS The role of DOW versus Kow Future needs Recommendation ABBREVIATIONS APPENDIX A: MEASUREMENT OF ACIDITY (pKA) APPENDIX B: MEASUREMENT OF PARTITIONING (KOW) APPENDIX C: MEASUREMENT OF SORPTION (Kd) APPENDIX D: MEASUREMENT OF HYDROLYSIS APPENDIX E: MEASUREMENT OF BIODEGRADATION BIBLIOGRAPHY MEMBERS OF THE TASK FORCE MEMBERS OF THE SCIENTIFIC COMMITTEE Summary Table 3 summarises the applicability of each of the methods reviewed above. They are further annotated in Appendix A. There is no particular recommendation.