The Dawning of a New Age of Toxicology

Toxicology faces enormous challenges in a world in which we are exposed to thousands of chemicals and millions of mixtures thereof. In response, radically new approaches need to be developed. A milestone in this direction is the vision of the national research council (NRC) of the USA "Toxicity testing in the 21st century: A vision and a Strategy". Currently, an alliance formed by the national toxicology program (NTP) and the chemcial genomics centre (NCGC) of the NIH and the computational toxicology centre (NCCT) of the EPA is testing whether this new strategy can realistically form the basis for future public health decisions. The visionrequires a radical paradigm shift in the approach to safety assessments, and turns the commonly known procedures upside down. Where animal experiments used to be the most important technology, the future is seen in the strength of in vitro and in silico approaches based on human material. Toxicity testing starts today with an initia lblack box screen on animals, sometimes followed by mechanistic studies, while the new vision approaches hazard assessment bottom up. The procedure would begin with in vitro tests to definethe perturbated pathways. To fill remaining gaps of knowledge a limited and targeted testing in animals would then be performed as potential second step.This means nothing less than changing toxicology, from being a predominantly observational craft and regulatory support discipline, to becoming again a natural science with all its dimensions. The background, the implications and parallel European trends are discussed here for interested Europeans.JRC.I.2-In-vitro Toxicolog