The conventional method for assessing the safety of products, ranging from pharmaceuticals to agrochemicals, biocides and industrial and household chemicals — including cosmetics — involves determining their toxicological properties by using experimental animals. The aim is to identify any possible adverse effects in humans by using these animal models. Providing safe products is undoubtedly of the utmost importance but, over the last decade or so, this aim has come into conflict with strong public opinion, especially in Europe, against animal testing. Industry, academia and the regulators have worked in partnership to find other ways of evaluating the safety of products, by non-animal testing, or at least by reducing the numbers of animals required and the severity of the tests in which they are used. There is a long way to go before products can be evaluated without any animal studies, and it may be that this laudable aim is an impossible dream. Nevertheless, considerable progress has been made by using a combination of in vitro tests and the prediction of properties based on chemical structure. The aim of this review is to describe these important and worthwhile developments in various areas of toxicological testing, with a focus on the European regulatory framework for general industrial and household chemicals.
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