25/9/2014 – The OECD endeavours to make better use of increased knowledge of how chemicals induce adverse effects in humans and wildlife, through the so-called Adverse Outcome Pathways. It is based on such knowledge that effective tools can be built to identify chemicals that need to be regulated. Adverse Outcomes Pathways (AOPs) provide a means of understanding how chemicals induce adverse effects through their toxicity pathways and modes of action. Since 2012, the AOP Development Programme at the OECD has been pioneering the establishment of a comprehensive AOP framework that can enable the more effective use of mechanistic information in regulatory decision-making.
As a major step forward towards this goal, a joint collaboration between the OECD, the U.S Environmental Protection Agency and the European Commission Joint Research Centre has today launched the Adverse Outcome Pathway Knowledge Base (AOP KB). This is a web-based platform which aims to bring together all knowledge on how chemicals can induce adverse effects, therefore providing a focal point for AOP development and dissemination. The first AOP KB module is the AOP Wiki: an interactive and virtual encyclopaedia for AOP development, structured in accordance with the original OECD "Guidance document and a template for developing and assessing adverse outcome pathways" (Series No. 184, Series on Testing and Assessment) and the more recent Handbook for AOP developers. The Wiki is an innovative knowledge-sharing tool.
All stakeholders from academia, governmental agencies and the chemical industry are invited to use the wiki either as a source of information, or as active contributors posting comments and content. This expert contribution from third-parties is strongly encouraged since it is through such "crowd sourcing" that the AOP KB will ultimately evolve.
Please see below for a more detailed description of this wiki tool. Additional questions can be addressed to Anne Gourmelon and Joop de Knecht at firstname.lastname@example.org or email@example.com in OECD’s Environment directorate.
A typical AOP within the Wiki consists of a series of interlinked articles and tables that describe its Molecular Initiating Event (MIE), Adverse Outcome (AO), and the associated series of intermediate Key Events (KE). The causal associations tying the MIE, KEs and AOs together are captured in the Key Event Relationships (KER) pages, together with the supporting evidence. An important feature of the Wiki is the ease with which developers can re-use MIE/KE/AO/KER articles created by others, modifying or adding to them if required.
The AOP Wiki is open to the public for (anonymous) read-access by default. Users can also register and therefore benefit from the discussion pages where they can post remarks on AOPs that have been opened for commenting. While freely accessible, anyone interested in gaining special access to insert their own AOP should first make a project proposal to the AOP Development Programme.
The AOP KB has been only recently made available to AOP developers. Thus the content of the Wiki is somewhat limited for the moment, with many AOPs in a state of construction and only a small number open for commenting. By opting for this early public release, the OECD aims to familiarise interested parties with AOP concepts and terminology through interaction with the AOP Wiki, with the hope of engaging as many potential AOP developers and contributors as possible.
The OECD is currently elaborating its process for the formal evaluation of AOPs by its various expert groups and decision-making bodies. Ultimately it is expected that adopted AOPs will inform the OECD Test Guidelines Programme regarding new in vitro test methods that could become OECD Test Guidelines, the OECD QSAR Project for the development of new methods/profilers for grouping chemicals, and the OECD Hazard Assessment activities for the design of Integrated Approaches to Testing and Assessment (IATA) of chemicals.
For more information: see Adverse Outcome Pathways, Molecular Screening and Toxicogenomics