Spielmann H, Kalweit S, Liebsch M, Wirnsberger T, Gerner I, Bertram-Neis E, Krauser K, Kreiling R, Miltenburger H G, Pape W, Steiling W
ZEBET, R.v. Ostertag Institut, BGA, PO Box 480 447, 1000 Berlin 48, Germany.
Toxicol In Vitro. 1993 Jul;7(4):505-10. doi: 10.1016/0887-2333(93)90055-a.
According to OECD guideline 405 revised in 1987 Draize eye tests need not be performed for severely irritating and corrosive chemicals if results from 'well-validated alternative studies' are presented. In 1988 a validation study on alternatives to the Draize eye test was started in Germany to establish 'well-validated alternative methods' for this purpose. During database development, the last stage of the validation programme, 136 chemicals from the German chemical industry were classified in a blind trial with the 3T3 cell neutral red/kenacid blue cytotoxicity assay and the hen's egg chorioallantoic membrane (HET-CAM) test using fertile chicken eggs. The major goal of this stage of validation was to demonstrate the feasibility and limitations of the two alternative methods. Chemicals were, therefore, selected as representatives of chemical structural groups as well as of physicochemical and toxicological properties. In addition, some of the chemicals were chosen because they were of interest to the cosmetic and detergent industries. Draize eye testing data in vivo were provided by industry. In contrast to data from a previous interlaboratory assessment trial, it was impossible to correlate cytotoxicity data to the EEC classification for in vivo eye irritation. However, seven of 10 severely irritating chemicals (EEC labelling R-41) could be identified correctly in the HET-CAM assay, whereas test conditions of the study described here did not allow identification of irritating chemicals (EEC labelling R-36). The HET-CAM test is, therefore, fulfilling the criteria of a 'well-validated alternative method' according to OECD guideline 405 and should be incorporated into eye irritation testing at the earliest possible stage to reduce effectively the suffering of rabbits in the Draize eye test. Although an 80% correct prediction of 'non-labelled' chemicals in the HET-CAM test is encouraging, for safety assessment of non-irritant chemicals, for use as cosmetic formulations, for example, both government and industry will accept an in vitro assay only if its prediction of the absence of irritant properties is 100% correct.
根据经合组织1987年修订的第405号准则，如果能提供“充分验证的替代研究”结果，则无需对具有严重刺激性和腐蚀性的化学品进行德莱兹眼刺激试验。1988年，德国启动了一项关于德莱兹眼刺激试验替代方法的验证研究，目的是为此建立“充分验证的替代方法”。在验证计划的最后阶段即数据库开发过程中，采用3T3细胞中性红/肯纳酸蓝细胞毒性试验和利用受精鸡蛋的鸡胚绒毛尿囊膜（HET-CAM）试验，对来自德国化学工业的136种化学品进行了盲法分类。这一验证阶段的主要目标是证明这两种替代方法的可行性和局限性。因此，化学品的选择既作为化学结构组的代表，也考虑了其物理化学和毒理学特性。此外，选择一些化学品是因为它们受到化妆品和洗涤剂行业的关注。体内德莱兹眼刺激试验数据由行业提供。与之前的实验室间评估试验数据不同，无法将细胞毒性数据与体内眼刺激的欧盟分类相关联。然而，在HET-CAM试验中，10种具有严重刺激性的化学品（欧盟标签R-41）中有7种能够被正确识别，而此处所述研究的试验条件无法识别刺激性化学品（欧盟标签R-36）。因此，根据经合组织第405号准则，HET-CAM试验符合“充分验证的替代方法”的标准，应尽早纳入眼刺激试验，以有效减少兔子在德莱兹眼刺激试验中的痛苦。尽管HET-CAM试验中对“无标签”化学品80%的正确预测令人鼓舞，但对于非刺激性化学品的安全评估，例如用作化妆品配方时，只有当体外试验对无刺激特性的预测100%正确时，政府和行业才会接受。
