Hyalella azteca bioconcentration test (HYBIT)

ECHA recently announced that the Hyalella azteca bioconcentration test (HYBIT) can fulfil the standard information requirement under REACH for bioaccumulation, unless dietary exposure is required (read more). Thereby, the bioconcentration test (OECD TG 305) with fish will be replaced on a case-by-case basis with a test system that uses freshwater amphipods, i.e. non-vertebrates. A test guideline for the HYBIT has been adopted in June 2024 (OECD TG 321). This vertebrate-free alternative test method is considered currently only for chemicals regulated under REACH.

The HYBIT has been validated in an international ring test (see the ring test report), in which ECT has participated. We have already been successfully conducting the HYBIT in compliance with Good Laboratory Practice (GLP).

For additional information on the bioaccumulation tests performed by ECT, see here.