The scientific community has been working vigorously towards Reduction/Replacement/Rehabilitation of the animals used for research. The agencies like ICCVAM, ECCVAM with active involvement of scores of scientists have been working on developing the experimental protocols for ensuring minimisation of the invivo studies. Amongst these, the most painful one was the studies requiring testing the compounds for their potential to cause severe pain and distress in the animal under testing. Their efforts led to development of a harmonized study protocol, which was one of the test method formalized by OECD TG No. 437 replacing the in vivo testing of corrosive test articles by a new in vitro eye irritation. This test enables prediction of across the full range of irritation for different chemical classes. BCOP test method is on of the vital test in the series of test recommended by OECD as it addresses corneal effects, which are the major driver of classification in-vivo when considering the UNGHS classification.

The purpose of this study is to evaluate the eye hazard potential of a test item by measuring its ability to induce opacity and increased permeability in an isolated bovine cornea. Toxic effects to the cornea are measured by: (i) decreased light transmission (opacity) and (ii) increased passage of sodium fluorescein dye (permeability). The opacity and permeability assessments of the cornea following exposure to a test chemical are combined to derive an In Vitro Irritancy Score (IVIS), which is used to classify the irritancy level of the test chemical.
The BCOP test method is an organotypic model that provides short-term maintenance of normal physiological and biochemical function of the bovine cornea in vitro. The method used Corneas of Bovine eyes from the abattoirs. The eyes are of no commercial value and are discarded as biological waste.