There is a vital safety requirement to appropriately warn users of chemical products that have acute hazards. As there is a very large amount and wide variety of chemical products, there is also a need to generalize acute hazards of chemicals so they can be reduced to a standardized, simple warning that can be found on a safety datasheet or product label. Acute lethality provides one simple, generalized indicator of the toxicity of a chemical product. The acute lethality hazard is typically determined using the LD₅₀ which is defined as the median dose predicted to kill 50% of a given test population. The purpose of this paper is to provide a review of the LD₅₀, including its history, the current studies used to develop it, and its integrated role in hazard communication. Continual improvement in animal welfare and reduction in animal costs has been one of the primary drivers of change for the LD₅₀ and its regulatory integration. There are currently several well-established animal testing protocols designed to minimize the number of animals needed to produce an LD₅₀ estimate that is sufficient for acute toxicity hazard communication. The utility of these animal testing protocols is further enhanced by ongoing regulatory adoption of The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) that integrates LD₅₀ data into a common hazard communication language. GHS can allow for multiple regulatory agencies to enforce a single and consistent hazard communication for a chemical or mixture without requiring new animal testing. This paper reviews the current progress and limitations of LD₅₀ integration with GHS as well as approaches that can be taken to better streamline integration.

中文翻译：

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LD ₅₀及其在危害交流中的当前作用的回顾

有一个非常重要的安全要求，即要适当警告具有急性危害的化学产品使用者。由于化学品的种类繁多，因此也需要对化学品的急性危害进行概括，以便将其简化为可在安全数据表或产品标签上找到的标准化简单警告。急性致死性提供了一种简单，通用的化学产品毒性指标。急性致死性危险通常使用LD ₅₀来确定，LD ₅₀定义为预计会杀死给定测试人群50％的中值剂量。本文的目的是对LD ₅₀进行回顾包括其历史，当前用于开发它的研究以及其在危害交流中的综合作用。动物福利的不断提高和动物成本的降低一直是LD ₅₀及其监管整合变革的主要动力之一。当前，存在几种完善的动物测试规程，旨在最小化产生足以进行急性毒性危害通报的LD ₅₀估计值所需的动物数量。通过持续采用与LD ₅₀集成的全球化学品统一分类和标签制度（GHS）的法规，这些动物测试规程的实用性得到了进一步增强。数据转换为常见危害交流语言。GHS可以允许多个监管机构对化学品或混合物强制执行单一且一致的危害通报，而无需进行新的动物试验。本文回顾了LD ₅₀与GHS集成的当前进展和局限性，以及可以用来更好地简化集成的方法。