Langbein T, Sonntag H, Trapp D, Hoffmann A, Malms W, Röth E P, Mörs V, Zellner R
Department of Anaesthesia, Georg-August-Universität, Göttingen, Germany.
Br J Anaesth. 1999 Jan;82(1):66-73. doi: 10.1093/bja/82.1.66.
The atmospheric lifetimes of the halogenated anaesthetics halothane, enflurane, isoflurane, desflurane and sevoflurane with respect to reaction with the hydroxyl radical (OH.) and UV photolysis have been determined from observations of OH. reaction kinetics and UV absorption spectra. Rate coefficients for the reaction with OH radicals for all halogenated anaesthetics investigated ranged from 0.44 to 2.7 x 10(-14) cm3 molec-1 s-1. Halothane, enflurane and isoflurane showed distinct UV absorption in the range 200-350 nm. In contrast, no absorption in this wavelength range was detected for desflurane or sevoflurane. The total atmospheric lifetimes, as derived from both OH. reactivity and photolysis, were 4.0-21.4 yr. It has been calculated that up to 20% of anaesthetics enter the stratosphere. As a result of chlorine and bromine content, the ozone depletion potential (ODP) relative to chlorofluorocarbon CFC-11 varies between 0 and 1.56, leading to a contribution to the total ozone depletion in the stratosphere of approximately 1% for halothane and 0.02% for enflurane and isoflurane. Estimates of the greenhouse warming potential (GWP) relative to CFC-12 yield values of 0.02-0.14, resulting in a relative contribution to global warming of all volatile anaesthetics of approximately 0.03%. The stratospheric impact of halothane, isoflurane and enflurane and their influence on ozone depletion is of increasing importance because of decreasing chlorofluorocarbons globally. However, the influence of volatile anaesthetics on greenhouse warming is small.
通过对羟基自由基（OH.）反应动力学和紫外吸收光谱的观测，已确定了卤代麻醉剂氟烷、恩氟烷、异氟烷、地氟烷和七氟烷与羟基自由基（OH.）反应以及紫外光解的大气寿命。所研究的所有卤代麻醉剂与OH自由基反应的速率系数范围为0.44至2.7×10⁻¹⁴ cm³ 分子⁻¹ s⁻¹。氟烷、恩氟烷和异氟烷在200 - 350 nm范围内表现出明显的紫外吸收。相比之下，未检测到地氟烷或七氟烷在该波长范围内有吸收。由OH.反应性和光解得出的总大气寿命为4.0 - 21.4年。据计算，高达20%的麻醉剂进入平流层。由于氯和溴的含量，相对于氯氟烃CFC - 11的臭氧消耗潜能值（ODP）在0至1.56之间变化，导致氟烷对平流层总臭氧消耗的贡献约为1%，恩氟烷和异氟烷为0.02%。相对于CFC - 12的温室变暖潜能值（GWP）估计值为0.02 - 0.14，导致所有挥发性麻醉剂对全球变暖的相对贡献约为0.03%。由于全球氯氟烃的减少，氟烷、异氟烷和恩氟烷对平流层的影响及其对臭氧消耗的影响变得越来越重要。然而，挥发性麻醉剂对温室变暖的影响很小。
