Vinegar A
ManTech Environmental Technology, Inc at Wright-Patterson AFB, OH, USA.
Aviat Space Environ Med. 2001 Oct;72(10):928-36.
Halon 1301 and Halon 1211 are being replaced because they contribute to the depletion of ozone. Many of the potential candidate chemicals for replacing them are, like them, halogenated hydrocarbons. These chemicals have the potential to cause cardiac sensitization at high enough exposure concentrations.
A physiologically based pharmacokinetic model, which mathematically describes the uptake, distribution, metabolism, and elimination of chemicals, was used to relate exposure to these chemicals with arterial blood concentrations resulting from the exposure. This information was then used to evaluate the potential for the occurrence of a cardiac-sensitizing event. The model was used to analyze the exposures to Halon 1301 and Halon 1211 in three aircraft (Navy E-2B, Cessna-421B, and Cessna-210C).
Halon 1301 exposures were shown to be safe, but Halon 1211 resulted in arterial concentrations in exposed individuals that reached levels that could potentially cause cardiac sensitization.
Use of the model for evaluating the risk from exposure to Halon 1301 and Halon 1211 is a moot point since both chemicals are being replaced. However, demonstration of the validity of the approach provides a tool for the evaluation of the health safety of replacement candidates. The National Fire Protection Association has approved use of this model for assessing times for safe egress from situations where agents are used to flood an area to extinguish a fire.
哈龙1301和哈龙1211正被淘汰，因为它们会导致臭氧层损耗。许多潜在的替代化学物质与它们一样，都是卤代烃。这些化学物质在足够高的暴露浓度下有可能导致心脏致敏。
使用基于生理学的药代动力学模型，该模型以数学方式描述化学物质的摄取、分布、代谢和消除，将这些化学物质的暴露与暴露后动脉血浓度联系起来。然后利用这些信息评估发生心脏致敏事件的可能性。该模型用于分析三架飞机（海军E-2B、塞斯纳-421B和塞斯纳-210C）中哈龙1301和哈龙1211的暴露情况。
结果表明哈龙1301的暴露是安全的，但哈龙1211导致暴露个体的动脉浓度达到可能引起心脏致敏的水平。
由于这两种化学物质都在被替代，使用该模型评估哈龙1301和哈龙1211暴露风险已无实际意义。然而，该方法有效性的证明为评估替代候选物的健康安全性提供了一种工具。美国国家消防协会已批准使用此模型来评估在使用灭火剂淹没区域灭火的情况下安全疏散所需的时间。
