On December 19, 2016 the Organisation for Economic Cooperation and Development (OECD) published a guidance on the use of adverse outcome pathways (AOPs) in developing integrated approaches to testing and assessment (IATA). In March 2017, this document was published in its final edited form in OECD’s Series on Testing and Assessment.

OECD explains that IATA are “pragmatic, science-based approaches for chemical hazard characterization,” which rely on integrating the existing information along with new information generated by targeted testing with use of a combination of traditional and novel testing methods. AOPs are conceptual models that offer a way to systematically collect, organize, and evaluate knowledge on toxicity mechanisms (see FPF background article). In IATA, AOP framework can be used “to characterize the individual biological and toxicological relevance of novel methods in predicting an adverse effect,” in order “to inform their potential use in combination with other tools and methods to benefit from an integrated approach.”

The OECD guidance provides several examples of how AOPs can be used to support IATA, including the development of (quantitative) structure-activity relationship (Q)SAR models, grouping of chemicals into chemical categories, development of testing strategies, interpretation of results from non-standard test methods, and prioritization of methods to be developed and refined in the frame of the Test Guideline program. It further discusses the areas of uncertainty in the development of IATA based on AOPs.  The potential use and misuse of AOPs in risk assessment has been critically discussed by a non-government organization Pesticide Action Network (PAN) Europe in a report published in December 2016 (FPF reported).

In March 2017 the OECD released the e.AOP.Portal to serve as the main entry point to the AOP-Knowledge Base (AOP-KB). The e.AOP.Portal provides a search engine supporting the browsing of available AOPs and related documents.

Read more

OECD (2017). “Integrated Approaches to Testing and Assessment (IATA).


OECD (2017). “Guidance document for the use of Adverse Outcome Pathways in developing Integrated Approaches to Testing and Assessment (IATA).OECD Environment, Health and Safety Publications, Series on Testing & Assessment No. 260, ENV/JM/MONO(2016)67 (pdf).