IMPROVING OUR UNDERSTANDING OF THE ENVIRONMENTAL PERSISTENCE OF CHEMICALS.

Significant progress has been made in the scientific understanding of factors which influence the outcome of biodegradation tests used to assess the persistence (P) of chemicals. This needs to be evaluated to assess whether recently acquired knowledge could enhance existing regulations and environmental risk assessments. Biodegradation tests have limitations, which are accentuated for 'difficult to test' substances and failure to recognise these can potentially lead to inappropriate conclusions regarding a chemical's environmental persistence. Many of these limitations have been previously recognised and discussed in a series of ECETOC reports and workshops. These were subsequently used to develop a series of research projects designed to address key issues and, where possible, propose methods to mitigate the limitations of current assessments. Here, we report on the output of a Cefic LRI - Concawe Workshop held in Helsinki on 27th September 2018. The objectives of this workshop were to disseminate key findings from recent projects and assess how new scientific knowledge can potentially support and improve assessments under existing regulatory frameworks. The workshop provided an unique opportunity to initiate a process to re-examine the fundamentals of degradation and what current assessment methods can achieve by 1) providing an overview of the key elements and messages coming from recent research initiatives and 2) stimulating discussion regarding how these interrelate and how new findings can be developed to improve persistence assessments. Opportunities to try and improve understanding of factors affecting biodegradation assessments and better understanding of the persistence of chemicals (particularly UVCBs [substances of Unknown or Variable Composition, complex reaction products or Biological materials]) were identified and the workshop acted as a catalyst for further multi-stakeholder activities and engagements to take the persistence assessment of chemicals into the 21st Century. This article is protected by copyright. All rights reserved.