Guidance Document on Considerations for Waiving or Bridging of Mammalian Acute Toxicity Tests

Acute toxicity tests are an area of focus for developing alternative assays and approaches to address animal welfare concerns. In the context of this document, acute toxicity studies refer to studies involving a single exposure to a test chemical and include those assessing systemic toxicity as well as those assessing local irritation, corrosion or sensitization. One approach to minimizing the use of animals for acute toxicity testing is to consider waiving a study that may be required based on scientific criteria. Another approach to reducing or eliminating animal testing is to use existing hazard information that is informative for the acute toxicity endpoint for the test chemical; this would include the use of hazard information for one or multiple similar test chemicals to characterize the hazard for another or for mixtures, the use of recognized calculation approaches and bridging concepts. This Document provides clarification on these approaches to ensure that regulatory authorities are provided with the appropriate data required for decision-making and that reduced animal testing can be undertaken without compromising the integrity of the hazard information.