Ocular Lens Organ Culture as a Measure of Ocular Irritancy: The Effect of Surfactants

An in vitro alternative for ocular irritancy testing, using the optical response of the cultured bovine ocular lens, has been developed. The method incorporates a relatively simple computer-operated device that objectively measures focal length characteristics of the intact lens. A preliminary test of this approach, involving the testing of five alcohols, showed it produces results that are comparable with those of the Draize and corneal thickness measures of irritancy. The present study examines the effects three concentrations of each of six surfactants (benzalkonium chloride, cetylpyridinium bromide, sodium dodecyl sulfate, Geropon AC-78, Triton X-100, and Tween 20) on bovine lens optics. The concentration limits for the six surfactants were 0.01-5.0%. The results showed that increased focal variability (loss of sharp focus) is a very sensitive indication of lens damage. At a common concentration of 0.1%, the six compounds produced widely different effects, as defined by the time to produce a 100% increase in focal variability. The order of damage caused by the six compounds is similar to Draize and corneal swelling results for the same substances. It is suggested that this approach is a sensitive, relevant, and objective in vitro alternative that deserves further validation study.