Globally Linking Scientific Knowledge through the Adverse Outcome Pathways Wiki

By Steve Edwards, Ph.D.

I am thrilled to announce that on September 25th, we and our partners released the online Adverse Outcome Pathway (AOP) Wiki—an interactive, virtual encyclopedia for the development and evaluation of adverse outcome pathways.

An AOP is a conceptual framework that shows what is known about the “pathways,” or links between a chemical and how it: interacts with a biological process, initiates direct changes on a molecular level, and leads to an environmental and human health risk, or “adverse outcome.”

It is important for us to understand and map AOPs in order to incorporate toxicological data into chemical risk assessments and regulatory decision-making.

Our goal for the AOP Wiki was to create an easy-to-use tool that will stimulate, capture, and use crowd-sourced knowledge from the scientific community. Using the Wiki’s user-friendly interface and standardization guidance, we have created a tool to allow scientists from all industries and disciplines to develop, evaluate, and use adverse outcome pathways.

All AOPs within the wiki are constructed using guidance from two reports of the Organization for Economic Co-operation and Development’s (OECD) Extended Advisory Group on Molecular Screening and Toxicogenomics (Guidance on Developing and Assessing Adverse Outcome Pathways and the AOP Developers’ User Handbook). What I find particularly helpful about the guidance and wiki design is that it provides a user-friendly experience with consistent terminology and useful widgets for navigation and development. This way AOP developers and other users without extensive experience with Wiki language can take full advantage of the available information.

AOP Knowledge Base

AOP Knowledge Base

Our Wiki is the first publicly released module of the larger AOP Knowledge Base (AOP KB). This international collaboration will provide a consolidated, comprehensive knowledge base on how chemicals can induce adverse effects. Through quality user engagement, we want the knowledge base to evolve and become the focal point for AOP development and dissemination. Our next step is to integrate the wiki with the other AOP KB modules in development:

  • AOP Xplorer
    A graphic computer module that will allow scientists worldwide to create graphics that highlight how several different AOPs might interconnect and adversely affect the same biological system. (Expected release later this year.)
  • Intermediate Effects Database
    Will host chemical-related data derived from non-traditional methods.
  • Effectopedia
    Will bring together scientists and studies from different disciplines to share data about different species and biological organization, chemical exposure routes and durations, and much more.

With these tools, we are taking strides toward connectingthe sequence of events that unfold after chemical interaction sparks changes on the molecular level of a biological system, and cascades on until an adverse health outcome. The Advanced Outcome Pathway Wiki is a collaborative effort of the EPA, the OECD, the international scientific community, the European Joint Research Center, and the U.S. Army Corp of Engineers. For more information on this project, please see our fact sheet.

About the Author: EPA systems biologist Stephen Edwards is developing a framework to improve the scientific underpinnings of the Agency’s human and ecological risk assessments. He serves as a senior Agency advisor on the development of predictive toxicology models of disease using genomics, proteomics, and metabolomics.

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