A rapid testing procedure to determine low levels of ocular irritation.
A new and rapid method for testing low levels of ocular irritation using a balanced incomplete block design, a new grading system, and statistical analysis of the results, has been developed. Two drops (0.1 ml) of 1 of 5 ophthalmic solutions were instilled into the conjunctival sac of the right or left eye of each of 10 New Zealand white [Deb:(NZW)] rabbits hourly for 9 hr on 4 consecutive da. Before the study and before the first instillation on each day, the eyes were examined with a direct ophthalmoscope, and the reactions were graded according to a modification of the system in the illustrated Guide for Grading Eye Irritation by Hazardous Substances. The new procedure showed that 1 of the 5 solutions elicited a significantly more severe (p less than or equal to 0.05) ocular response of redness, chemosis, and discharge than did any of the other 4 solutions. Previous testing of this solution in rabbits by standard laboratory procedures and the Draize method of grading ocular irritation failed to detect these reactions.
D000818:Animals; D001548:Benzalkonium Compounds / Q000008:administration & dosage / Q000494:pharmacology*; D003228:Conjunctiva / Q000187:drug effects; D003315:Cornea / Q000187:drug effects; D004353:Drug Evaluation, Preclinical; D005123:Eye / Q000187:drug effects*; D007498:Iris / Q000187:drug effects; D007509:Irritants; D008722:Methods; D009883:Ophthalmic Solutions; D011817:Rabbits
D001548:Benzalkonium Compounds; D007509:Irritants; D009883:Ophthalmic Solutions