Viability of developing a screening tool to assess non-standard bioaccumulation potential of chemical substances in aquatic and terrestrial wildlife

Descriptions

"The Chemical Assessment Unit (CAU; Chief Scientist's Group - Research, Environment and Business Directorate, Environment Agency) supports the UK Chemicals Agency (the Health and Safety Executive, HSE) on the environmental aspects of the UK Registration, Evaluation, Authorisation and restriction of Chemicals (REACH) legislation. A crucial part of our work is hazard assessment of industrial and consumer chemicals, and the correct assignment of bioaccumulation potential is a fundamental component of such assessments. Currently, there are no validated test guidelines or methods to screen for chemicals that preferentially bioaccumulate in non-lipid rich tissues (e.g. muscle, liver, serums). This project aims to identify what alternative tests are available or could be developed and used to screen for this form of bioaccumulation as a regulatory requirement under UK REACH; specifically in relation to Persistent, Bioaccumulative and Toxic and very Persistent very Bioaccumulative (henceforth PBT) assessment and exposure modelling. If suitable methods can be identified, we would like to understand how they would trigger the determination of BioConcentration Factors (BCF;or other bioaccumulation metrics) in aquatic and dietary exposure studies. For example, can equivalent threshold metrics, e.g.: •Log KOW > 4.5 be established for screening for a high potential for bioaccumulation in an aquatic organism •Log KOW > 2 (in combination with a log KOA¬ > 5) be established for a high potential for bioaccumulation in air-breathing organisms. The objective of this project is to provide relevant up-to-date evidence and understanding on the types of study that could inform non-standard accumulation processes in aquatic and terrestrial wildlife. It will also provide a critical review of current understanding and contemporary methods, identifying uncertainties in generated data and the applicability of methods to different substance types. "