In a recent paper, FREIA partners Terje Svingen (DTU) and Pauliina Damdimopoulou (KI) propose an approach to speed up the development and acceptance of mechanistic descriptions that are used by chemical safety assessors and regulators.
Adverse Outcome Pathways (AOPs) are a way to organise scientific knowledge and describe how a stressor – such as exposure to an endocrine disrupting chemical – can lead to a harmful health effect through a chain of linked events. The use of AOPs is gaining wide acceptance and will help to support chemical safety assessors and regulators.
Yet, only a few AOPs are thoroughly evaluated and endorsed by the Organisation for Economic Co-operation and Development (OECD), which clearly hampers their regulatory use. A major hurdle is the immense amount of work that has to be put into the development of an AOP. “Putting together the information for one key event relationship (the link between two sequential events in an AOP – red.) took me about three months altogether”, explains Eleftheria Panagiotou, PhD student involved in this work.
“We propose to focus more on smaller building blocks and rely more on existing common knowledge”, says lead author Terje Svingen. The approach will make it more attractive for scientists to contribute to AOPs, because in this way, they can focus on their own expertise and don’t have to be an expert on all facets of an AOP from molecular interactions to health effects.
Moreover, a description of a smaller AOP building block makes an excellent paper to be submitted for peer-review. Besides the scientific merit, publishing the building blocks has the added advantage that external peer-reviewers have already critically evaluated the information. This may stimulate faster endorsement of AOPs by the OECD. “It is our hope that our proposed approach will increase the pace at which the AOP knowledge base is populated with endorsed AOPs, which will certainly improve chemical safety assessment processes.”, according to the authors of this paper.
Terje Svingen, Daniel L. Villeneuve, Dries Knapen, Eleftheria Maria Panagiotou, Monica Kam Draskau, Pauliina Damdimopoulou, Jason M O’Brien. A pragmatic approach to Adverse Outcome Pathway (AOP) development and evaluation. Toxicological Sciences, kfab113, https://doi.org/10.1093/toxsci/kfab113 Published: 17 September 2021