OECD 437 Flashcards
What is the purpose of the Bovine Corneal Opacity and Permeability (BCOP) test method?
To identify chemicals inducing serious eye damage and those not requiring classification for eye irritation or serious eye damage
The test is crucial for evaluating the eye irritation potential of chemicals.
Which organizations evaluated the BCOP test method?
ICCVAM, ECVAM, JaCVAM
These evaluations took place in 2006 and 2010.
What were the two main evaluations of the BCOP test focused on?
- Identifying chemicals causing serious eye damage (UN GHS Category 1)
- Identifying chemicals not requiring classification for eye irritation or serious eye damage (UN GHS No Category)
When was the Test Guideline (TG) for the BCOP test first adopted?
2009
Updates followed in 2013 and 2020.
What significant update was made to the BCOP test in 2020?
Allowed the use of a laserlight-based opacitometer (LLBO) alongside the OP-KIT opacitometer.
Is the BCOP test a stand-alone replacement for the in vivo Draize eye test?
No, it is recommended to be used as part of a tiered testing strategy.
What are the two approaches used in the BCOP test for assessing chemicals?
- Top-Down approach for high irritancy potential
- Bottom-Up approach for low irritancy potential
What does the BCOP test measure to assess eye irritation potential?
- Opacity (decreased light transmission)
- Permeability (increased passage of sodium fluorescein dye)
What is the In Vitro Irritancy Score (IVIS) based on?
Combination of opacity and permeability measurements.
What is the overall accuracy of the BCOP OP-KIT when compared to the in vivo rabbit eye test?
79% overall accuracy
It has 25% false positive and 14% false negative rates.
What is the accuracy of the BCOP LLBO when compared to the in vivo rabbit eye test?
78% overall accuracy
It has 21% false positive and 24% false negative rates.
What is the accuracy of the BCOP OP-KIT for identifying chemicals not requiring classification?
69% accuracy
It has a 69% false positive and 0% false negative rate.
What is a significant limitation of the BCOP test method?
It does not assess conjunctival and iridal injuries or the reversibility of corneal lesions.
What should laboratories new to the BCOP test use to demonstrate competence?
Proficiency substances
What is the principle of the BCOP test method?
An organotypic model that maintains the physiological and biochemical functions of bovine cornea in vitro.
How are bovine eyes sourced for the BCOP test?
From freshly slaughtered cattle, typically for human consumption or commercial uses.
What is the recommended transport method for enucleated eyes?
Eyes should be immersed in Hanks’ Balanced Salt Solution (HBSS) to prevent contamination.
When should eyes be used after collection for testing?
On the same day they are collected.
What criteria must eyes meet before use in the BCOP test?
- Free from defects like opacity, scratches, or neovascularization
- Specific opacity and light measurement requirements
What types of controls are included in the BCOP test?
- Negative controls (e.g., saline, distilled water)
- Positive controls (e.g., ethanol or dimethylformamide)
What is measured to quantify permeability in the BCOP test?
The amount of sodium fluorescein dye that penetrates the cornea.
What is the formula for calculating the In Vitro Irritancy Score (IVIS) with the OP-KIT?
IVIS = mean opacity value + (15 x mean permeability OD490 value)
What should be done if test results are borderline?
A second (and possibly third) testing run may be considered.
What is the study acceptance criterion for positive controls?
The test is acceptable if it falls within two standard deviations of the historical mean of IVIS or opacity.
