Completed Task Force

Mode of Action and Identification of Adverse vs. Non-adverse Effects

Task Force Manager Alan Poole

Administrative Assistant Christine Yannakas


The scientifically sound discrimination between adverse and non-adverse effects has always been a key element in the evaluation of toxicological results. ECETOC“s Task Force “Recognition of, and differentiation between, adverse and non-adverse effects in toxicology studies‘ (TR 85) has addressed this issue principally in terms of classical biochemical and histopathological endpoints.

However over the last several years, new technologies (principally “omics) are being used to explore toxicological mechanisms through changes of unknown relevance to harmful outcomes. While there is an accepted regulatory tradition in distinguishing observable effects of toxicological significance from those which are not considered adverse, this convention does not yet exist for these new technologies.