Procedure:
(1) Young albino New Zealand rabbits are selected at random, including both sexes.
(2) Both eyes were examined to exclude pre-existing ocular lesions.
(3) The test material was applied to one eye with the lids retracted, with the second eye untreated to serve as the control. The eyelids were released immediately and not forcibly closed, manipulated or irrigated.
(4) Eyes were examined at 1, 2, 3, 7, 14 and 21 days after dosing according to the scale of Draize et al. Examination is discontinued at any time during the test if there is not evidence of irritation.
Criteria for a Positive Test:
(1) ulceration of the cornea (exception: fine stippling)
(2) opacity of the cornea (exception: slight dulling of the normal luster)
(3) inflammation of the iris (exceptions: slight deepening of the folds or rugae; or slight circumcorneal injection of the blood vessels)
(4) diffuse crimson-red with individual vessels of the conjunctivae not easily discernible
Interpretation:
• A test is positive by FHSA criteria if any one of the significant findings is seen at any reading (at 24, 48 or 72 hours).
Limitations:
• The rabbit eye irritation test has been found to be more severe and persistent than that observed in humans (Beckley, 1965; Carter and Griffith, 1965).