The increased acceptance of SAR techniques in the regulatory arena to predict health and ecological hazards (1-6) has resulted in the development and marketing of a number of SAR programs (7). The approaches are of optimal usefulness when they are employed as adjuncts to the appropriate

human expertise. In addition to predicting specific toxicological endpoints, these methodologies, in the hands of an expert, can also be used to gain insight into the mechanistic basis of the action of toxicants and thereby allow a more refined health or ecological risk assessment (8,9).