Workshop Entitled “Consensus List of Developmental Toxicants”

Workshop Overview

There continue to be many efforts around the world to develop assays that are shorter than the traditional embryo fetal developmental toxicity assay, or use fewer or no mammals, or use less compound, or have all three attributes. Each assay developer needs to test the putative assay against a set of performance standards, which traditionally has involved testing the assays against a list of compounds that are generally recognized as "positive" or "negative" in vivo. However, developmental toxicity is highly conditional, being particularly dependent on magnitude (i.e. dose) and timing of exposure, which makes it difficult to develop lists of compounds neatly assigned as developmental toxicants or not.

Approach

Here we offer an alternative approach for the evaluation of developmental toxicity assays based on exposures. Exposures are classified as "positive" or "negative" in a system, depending on the compound and the internal concentration. Although this linkage to "internal dose" departs from the recent approaches to validation, it fits well with widely accepted principles of developmental toxicology.

Workshop Objectives

This workshop introduced and discussed this concept including the benefits and drawbacks of this approach, and then reviewed, discussed, and evaluated the proposed list of developmental toxicants based on the recent paper that described the approach (Birth Def. Res Part B 89(6):526-530, 2010). The Workshop was designed to help pressure-test the approach and specifically evaluate, in breakout sessions, the utility of the proposed compounds and their effective and non-effective concentrations.

Please click here to download a copy of the draft workshop agenda.

For more information on this workshop, please contact Dr. James Kim at jkim@hesiglobal.org.