The SDA Alternatives Program Phase III: Comparison of in Vitro Data with Animal Eye Irritation Data on Solvents, Surfactants, Oxidizing Agents, and Prototype Cleaning Products

Abstract

Nine in vitro candidate tests for estimating eye irritation potential were evaluated as potential replacements for the Draize test. The tests examined were a cell protein assay, the chorioallantoic membrane vascularization assay, a cell protein assay, a fibroblast cytotoxicity assay, the Living Dermal Model and Living Skin Equivalent, two neutral red assays, an SIRC cytotoxicity assay, and a Tetrahymena thermophila motility assay. The results from these in vitro tests were compared to results from a modified Draize test with 22 test materials. The test materials were selected to represent various classes of cleaning products and ingredients. Ingredients were tested at concentrations representative of concentrations typically found in cleaning products. The correlation coefficients with all test materials considered ranged from 0.58 to 0.91. When only nonalkaline materials are considered, the correlation coefficients of all 10 tests were not significantly different from one another, ranging from 0.8 to 0.9. The assays least affected by the alkalinity of the test substances were the corneal epithelial plasminogen activator assay, the chorioallantoic membrane vascular assay, and the Tetrahymena motility assay. Further, six of the 10 tests were able to identify the five nonirritants in the study, although the relative irritation potentials of the irritants were not accurately predicted by any of the tests. Results from a low-volume eye irritation test (LVET) were also compared to results from a modified Draize test with the same 22 test materials. The LVET had a high correlation with the modified Draize test and will be useful for future comparison with other alternative eye irritation tests. Based on these data, a number of alternative tests developed to replace the Draize eye irritation test included in this phase of research are useful for screening the eye irritation potential of nonalkaline cleaning products, although some tests are better for identifying the eye irritation potential of test materials with alkaline or oxidation potential. Although the ability of the eye to recover from damage was not measured by any test, the tests show promise for the use of determining eye irritation potential.