1.1 该测试方法确定了杀伤力（LD50值、斜率和95 % 置信区间（CI））和使用有限数量大鼠的材料的急性毒性迹象。本试验方法中使用的技术称为“分段自适应剂量法” 2. 该试验方法是经典LD50试验的替代方法，适用于液体和固体。 1.2 对于通常在给药后两天以上导致死亡的试验材料，不建议使用本试验方法。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 该试验方法在最大限度地减少估计急性经口毒性（LD50）所需的动物数量方面具有重要价值。 它还结合了方差测量（95%置信区间）和斜率，从中进行相对毒性比较。 5.2 本试验方法不适用于通常在服用试验化合物两天或两天以上后产生死亡的材料，除非剂量之间的观察时间增加。然而，该试验方法可成功应用于给药后两天或两天以上偶尔死亡的材料。 5.3 LD50是衡量材料相对急性毒性的重要指标，可用于估计摄入农药、其他化学品或混合物时对人类的潜在危害。 5.4 该试验方法允许观察毒性迹象和死亡率。该信息可用于规划其他毒性测试。

1.1 This test method determines the lethality (LD50 value, slope and 95 % confidence interval (CI)) and signs of acute toxicity from a material using a limited number of rats. The technique used in this test method is referred to as the “Stagewise, Adaptive Dose Method.” 2 This test method is an alternative to the classical LD50 test and is applicable to both liquids and solids. 1.2 This test method is not recommended for test materials which typically produce deaths beyond two days postdosing. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 This test method is of principal value in minimizing the number of animals required to estimate the acute oral toxicity (LD50). It also incorporates measures of variance (95 % CI) and a slope from which to make relative toxicity comparisons. 5.2 This test method is inappropriate for materials typically producing death two or more days after administration of the test compound unless the observation time between dosages is increased. This test method can be successfully applied, however, for materials producing only an occasional death two or more days after administration. 5.3 The LD50 is valuable as a measure of the relative acute toxicity of a material and can be used to make an estimate of potential hazard to humans when pesticides, other chemicals, or mixtures are ingested. 5.4 This test method allows for observation of signs of toxicity in addition to mortality. This information can be useful in planning additional toxicity testing.