Improvement of the Bovine Corneal Opacity and Permeability (BCOP) assay as an in vitro alternative to the Draize rabbit eye irritation test.

•Better spreading of compounds in the LLBO scaling compared to the OP-KIT scaling.•The LLBO underestimated less the peripheral induced opacity compared to the OP-KIT.•Better separation of shampoos for their mild irritating potential using the LLBO.•Difference between the LLBO and OP-KIT in classifying formulations.•Adaptation of cornea holders is of limited value.