IN-VITRO MEASURE OF OCULAR DAMAGE AND RECOVERY FROM AROMATICS

An in vitro alternative to in vivo eye toxicity testing measures the f ocal length characteristics of the cultured bovine lens in response to potentially toxic chemicals. The validity of this approach was tested by comparing in vitro measures of damage, and recovery from damage, o f three aromatics subject to Draize testing. The optical quality of cu ltured bovine lenses was measured using a scanning laser system consis ting of a low-power helium-neon laser, video cameras, and a video fram e digitizer. Lenses were exposed to 100% toluene, styrene, and xylene for 30 or 60 min. Lenses were maintained in a culture environment befo re and after exposure. Damage and recovery measures were based on the time to produce a 100% increase in focal length variability (spherical aberration) or a 50% recovery (decrease) in focal length variability. The results indicate that the in vitro test provides a wider range of end values than in vivo data, making it easier to rank toxicity poten tial. The data also show that the in vitro method using the cultured l ens can measure the potential for recovery from damage.