The BCOP method uses cow eyes from the meat industry to measure corneal opacity with an opacitometer and permeability using a plate reader.
Lebrun Labs performs the test as described in OECD 437 using an Op-KitTM Opacitometer.
The OP-KIT opacitometer is a center-weighted reading of white polychromatic light transmission. Permeability is quantified using OD values of the amount of sodium fluorescein dye that passes through all layers. Using the opacity measurements and permeability OD values, an in vitro irritancy score (IVIS) is generated. A prediction model differentiates these scores into GHS NC and category 1 predictions. The OECD BCOP guideline states for the BCOP (OP-KIT) method that the overall accuracy was 69%, the FP rate was 69%, and the FN rate was 0%. For the BCOP (LLBO) method, the overall accuracy was 83%, the FP rate was 45%, and the FN rate was 6% (OECD 437, 2020a). The BCOP method can test solids and liquids, but it is not recommended for use with test chemicals that are classified as irritating to eyes (category 2B or 2A) due to a number of category 1 chemicals underclassified and a number of chemicals overclassified (OECD 437, 2020a).
Additional Reading:
Same-chemical comparison of nonanimal eye irritation test methods: Bovine Corneal Opacity and Permeability, EpiOcular™, Isolated Chicken Eye, Ocular Irritection®, OptiSafe™, and Short Time Exposure
For additional information contact: sales@lebrunlabs.com