New Version Released!

Version 2.0 of the AOP-Wiki was released on December 4, 2016.  This was a major upgrade and should provide a better user experience. It fixes a number of bugs with the previous version, provides a more streamlined user interface, and sets the stage for providing more programmatic access in 2017. 

All Wiki Users

All users with logins on the previous wiki will need to recreate their passwords.  More information is provided on the sign in page.  Your previous account including author status was transferred, but it is now tied to your email rather than the previous user name. If you are unsure of the email you had associated with your wiki login or have any problems, please email us at aopwiki@googlegroups.com.

Wiki Authors

Please note a few items resulting from the recent upgrade:

  • Author access to individual wiki pages is now restricted.  Each AOP from the previous wiki was assigned a point of contact based on the author information provided.  This point of contact has permission to add other contributors to the AOP at which point those contributors will have edit permissions.  All new AOPs will have the creator listed as point of contact. The point of contact can reassign to another contributor, but there can be only one point of contact.  Gardeners will still have edit permission on all AOP pages.
  • We encourage all AOP authors to compare the content in the current version of the wiki with the final version contained in this wiki. Great care was taken to maintain the integrity of the information during the migration, but there may be some discrepancies. The original version is permanently available here, and we are available to help if you have any problems correcting the issues in the new version. For comparison, you will use the following URLs (replacing 15 with your AOP #):

  • The naming convention for key events has been changed.  We no longer require a process/object and a separate action term.  This information will soon be captured using the new event components that are based on established biological ontologies.  We will be contacting authors of pre-existing AOPs on that topic soon.  We encourage all authors to check the names of the key events in their AOPs and adjust those names as needed.  We now include both a full title and short name for key events as we've always had for AOPs.

Firefox Users Redirecting to Old Wiki

We've had reports that users are being redirected into the old wiki when attempting to access the main page (this page) of the new wiki.  If you are using the Firefox web browser, this is due to the browser saving a cache of the location for the old web site locally on your computer.  To fix it, follow the instructions under the “Clear the cache” section in this link:


Please notify us at aopwiki@googlegroups.com if you experience this problem with a browser other than Firefox, and we will post the solution for those browsers too.  

Frequently Asked Questions

We are collecting solutions to all problems users nave noticed on our Frequently Asked Questions page:  https://aopwiki.org/info_pages/4. Please check there for answers if you have any problems. If you do not see your answer posted, email aopwiki@googlegroups.com, and we will work with you to solve the problem.

Thank you for your patience as we work through the migration issues associated with this major upgrade.

AOP Welcome

Welcome to the Collaborative Adverse Outcome Pathway Wiki (AOP-Wiki)

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If you are interested in contributing AOP-related knowledge to the AOP-KB, please follow the instructions laid out at the OECD Adverse Outcome Pathways, Molecular Screeing and Toxicogenomics page. The Guidance on Developing and Assessing AOPs document is the basis for all work related to contributing and sharing AOP-related knowledge. A Users' Handbook Supplement to this Gudance has been written to aid systematic development and transparent assessment of Adverse Outcome Pathways (AOPs). That handbook contains a template to guide AOP description and provides focused and practical instructions for develpers and assessors indended to assist in identifying, organizing, and evaluating critical information on key events and linkages (i.e., key event relationships (KER)) with the AOP, as well as guidance on how to assess the weight of evidence supporting the overall AOP.

This wiki represents a joint effort between the European Commision - DG Joint Research Centre (JRC) and U.S Environmental Protection Agency (EPA). This serves as one component of a larger OECD-sponsored AOP Knowledgebase effort and represents the central repository for all AOPs developed as part of the OECD AOP Development Effort by the Extended Advisory Group on Molecular Screening and Toxicogenomics. The other major components of this knowledgebase are Effectopedia, produced by the Organisation for Economic Co-operation and Development (OECD), the AOP Xplorer, produced by the US Army Corps of Engineers - Engineering Research and Development Center, and the Intermediate Effects DB produced by the JRC.

This wiki is based upon the Chemical Mode of Action wiki developed by the EPA under the auspices of the WHO International Programe on Chemical Safety (IPCS) Mode of Action Steering Group.


The content of this wiki is the sole responsibility of the individual contributors and does not necessarily represent the views of the Partner organizations. Mention of trade names or commercial products does not constitute endorsement by any of the Partner organizations.


Before you start

Please read the AOP Wiki Editing & Comments Policy.

General guidance on assembling AOP information in the AOP-Wiki is available in the OECD AOP Users' Handbook.

More detailed help can be found by clicking the Help link at the bottom of the page.

Additional information will be provided in the upcoming weeks.  We have launched a training wiki (https://training.aopwiki.org/) to allow users to learn the new system before making changes on the new production wiki. You do not need to be an author on this wiki to be granted author status on the training wiki, but all information in the training wiki is purged periodically and no mechanism exists to migrate information from that system to this one. If you have any questions or would like to request author privileges on the training wiki, please contact us at aopwiki@googlegroups.com.