Applying the bridging principles (see ECHA guidance on the application of the CLP criteria) can only be done if test data exist for similar mixtures (‘similar tested mixtures’) from which bridging is performed.

The CLP Regulation requires in Article 6(5) companies to use other available information on similar tested mixtures if no or inadequate test data on the mixture itself are available. The underlying concept encompasses the comparison (‘bridging’) of the scientific information and data pertinent to the assessment of the toxicological endpoint of interest (i.e., the skin or eye irritation/corrosion profile) of well-defined reference mixtures to newly developed detergent mixtures that are considered similar.