Eye irritancy screening for classification of chemicals.

A screening method was applied to determine the eye irritation potential of industrial chemicals. Bovine eyes (BE) were used to predict corneal damage and chicken egg chorioallantoic membranes (CAM) to estimate the irritancy potential of chemical substances towards the conjunctivae. Exposure of the BE to a test substance is followed by grading of the corneal opacity and epithelial injury. The CAM is inspected for signs of capillary injection, haemorrhages and coagulation. The tests are collectively called the BECAM assay. So far, almost 150 substances have been evaluated in this test system. A good correlation was observed between the BECAM assay and in vivo data; less than 5% of chemicals showed a clear disagreement. Also the assay is promising for labelling requirements according to the EEC criteria.