The problem of maternal toxicity in developmental toxicity studies

Guidelines for developmental toxicity studies require that the highest dose(s) should induce some signs of maternal toxicity. However, the interpretation of the results is often difficult when developmentally toxic effects are recorded only at maternotoxic doses, as it is impossible to ascertain whether the developmental effects are maternally mediated or not. In order to avoid this source of misinterpretation we suggest to use in developmental toxicity tests for environmental chemicals the maximum dose unable to produce maternal toxic effects extrapolated by previous short term toxicity studies.