HET-CAM METHOD AS AN ALTERNATIVE MODEL TO OCULAR IRRITATION TEST FOR NATURAL PRODUCT

Abstract

The society's pursuit of more sustainable products and natural raw materials has sparked scientific interest and prompted pharmaceutical and cosmetic industries to seek more sustainable alternatives. In 1944, Draize described the first tests for ocular irritation aimed at evaluating the degree of irritation caused by drugs, cosmetics, and other chemicals in rabbit eyes. Recently, CONCEA published the new normative resolution, No. 54, making the use of validated alternative methods with national or international regulatory acceptance mandatory. Given this context, the study aimed to evaluate the predictive potential of the alternative methodology using the chorioallantoic membrane of the chicken embryo (HET-CAM) and its modification (CAM-TBS), in order to propose alternatives for assessing the ocular toxicity of natural products with low irritant potential. The test products used were the crude extract of sapucaia seed byproduct, a natural emulsion base, and 10% urea cream, coded as A01, A02, and A03, respectively. In the HET-CAM assay, a false-negative result was observed, indicating inferior performance compared to CAM-TBS. The same product classified as "non-irritant" in the HET-CAM assay received a "mild irritant" classification in the CAM-TBS, indicating greater sensitivity of the CAM-TBS assay compared to HET-CAM. Based on the result, CAM-TBS demonstrated better performance compared to HET-CAM. To reduce the number of false negatives in HET-CAM, it is suggested to create a low irritant potential category with a cutoff point of 0.6 to 0.9, encompassing the "non-irritant" and "mild irritant" categories, similar to the CAM-TBS category.