Progressing toward the reduction, refinement and replacement of laboratory animal procedures: thoughts on some...

A variety of encounters with Dr Iain Purchase over the last 25 years are reviewed in relation to their significance in terms of progress toward the reduction, refinement and replacement of animal procedures in toxicology and toxicity testing. Included are the work of the first FRAME Toxicity Committee and the FRAME International Alternatives Validation Scheme, the International Conferences on Practical In Vitro Toxicology and the foundation of Toxicology in Vitro, the work of an Institute of Medical Ethics working party on issues raised by animal experimentation and alternative approaches, the need for in vitro assays for chemical carcinogenesis based on the transformation of human cells, the problem presented by the human hazard potential of thousands of chemicals already in use before modern regulations for the registration of new chemicals came into force, and the importance of testing strategies with a focus on the integrated use of non-animal computer-based and in vitro test systems.