Introduction

EECETOC has been actively involved in developing the scientific understanding of factors that affect the persistence of chemicals in the environment for over 15 years (see for example ECETOC, 2003, 2005, 2009, 2011). In 2007, ECETOC and the Environment Agency (EA) of England and Wales co-hosted a workshop on “Biodegradation and Persistence” at Holmes Chapel in the United Kingdom. Attendees from academia, regulatory agencies and industry discussed the challenges and uncertainty faced with persistency assessments at the screening and confirmatory testing level. Nine research topics were identified at the 2007 workshop and request for proposals (RfPs) were drafted to fill these research needs. From these, four RfPs were assigned highest priority for action. Significant progress has been made such that they are all at or near completion (see also Appendix 1). These include:

• Development of a validation set of chemicals for biodegradation research (funded by CEFIC/LRI and completed in 2010);
• Addressing the uncertainty associated with bound residues or non-extractable residues formed in higher tiered persistency assessments. This resulted in a subsequent ECETOC Workshop (ECETOC, 2009) and two ECETOC Task Forces which were due to report in 2013 (ECETOC, 2013a,b);
• Development of new persistency screening tools with biodegradation studies using enhanced biomass levels (funded by CEFIC/LRI and due for completion in 2013);
• Measuring biodegradation half-lives and identifying sources of variability and uncertainty (funded by CEFIC/LRI and project started in 2012).