Integrated Approaches to Testing and Assessment

The concept of Integrated Approaches to Testing and Assessment (IATA) has been advanced by the Organisation for Economic Cooperation and Development (OECD) member countries to enable a progressive shift from traditional chemical assessments largely based on the observation of the adverse effect in animal models, using individual methods or predefined batteries of standard toxicity tests, to assessment strategies integrating diverse lines of evidence. The flexible nature of IATA allows the inclusion of mechanistic data generated with non-animal methods and with new technologies (e.g. high-throughput and high content methods). The assessment process within IATA is typically conducted through weight-of-evidence which inevitably includes the elements of subjective expert judgement. For these reasons, IATA cannot be fully harmonized across sectors and countries. Nevertheless, some of the IATA components, such as defined approaches, which consist of a fixed data interpretation procedure (DIP) applied to data generated with a defined set of information sources, can be harmonized. The focus of this MiniReview is to provide an illustration of the differences between the IATA developed so far in the areas of regulatory toxicology, and ongoing activities related to the international harmonization of defined approaches that rely on multiple non-animal information sources.