There is no single in vitro ocular study available to replace the in vivo Draize test (OECD 405). However, the in vitro bovine corneal opacity and permeability (BCOP), the Isolated Chicken Eye (ICE) test (OECD 437) and EpiOcular™ or HCE 3D models (OECD 492) can be used together to classify many Class 1 chemicals and chemicals not requiring classification for eye irritation or serious eye damage, a viable 3Rs alternative. Where a classification is required, and the in vitro models do not give a clear overall prediction, the results of these tests can be used to justify performing the in vivo test.
You can use these models to screen your test article early in its development, or during GLP toxicology testing.
MatTek EpiOcular™ Assay or SkinEthic HCE Ocular Irritation Assay
These 3D models mimic human cornea epithelium. After treatment with a liquid or solid chemical the relative tissue viability is measured by photometrical measurement of formazan production by enzymatic reduction of MTT (MTT assay). In case no or limited toxicity is observed (non-irritant) the test chemical is identified as not requiring classification and labelling according to UN GHS No category.
Bovine Corneal Opacity and Permeability (BCOP) & Isolated Chicken Eye (ICE) Tests
The BCOP and ICE tests consist of topical application of a chemical on to corneal epithelium. They measure two important components which are predictive of irritation – corneal opacity, and permeability. The change in opacity and permeability values (OD490) will be used to calculate an in vitro score. This score can be used to identify the chemical as inducing serious eye damage (UN GHS category 1) or as a chemical not requiring classification for eye irritation or serious eye damage (UN GHS No Category).
Shining a Light on the Science and Strategy of Phototoxicity Assessments
In this podcast, Dr. Doug Learn, Director of Toxicology at Charles River Safety Assessment in Horsham, Pennsylvania, was interviewed. Dr. Learn is considered an expert in the field of phototoxicity. In this podcast, Dr. Learn shares his experiences during the evolution of how phototoxicity became a specialty field of its own, what phototoxicity means for toxicologists in the regulatory and pharmaceutical world, and how this translates to the consumer. Listen Now
Frequently Asked Questions FAQs for Ocular Irritation
What is an eye irritation test?
An eye or ocular irritation test uses a 3D model of eye tissue to assess the potential for a substance (such as a cosmetic product, pharmaceutical, chemical or agrochemical) to cause eye irritation when used by the consumer.
What is the BCOP test of eye irritation?
The bovine corneal opacity and permeability (BCOP) test is an in vitro study which can be used to determine whether a chemical (substance or mixture) should be classified as either causing “serious eye damage” or does not require classification under the Globally Harmonised System for the Classification and Labelling of chemicals.