Isocyanic acid in the atmosphere and its possible link to smoke-related health effects
Isocyanic acid in the atmosphere and its possible link to smoke-related health effects
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DOI：
10.1073/pnas.1103352108
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发表时间：
2011-05-31
影响因子：
11.1
通讯作者：
de Gouw, Joost
中科院分区：
文献类型：
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作者：
Roberts, James M.;Veres, Patrick R.;de Gouw, Joost
我们测量了实验室生物质火灾中的异氰酸(HNCO)，其含量高达百万分之600(Ppbv)，表明它有一个重要的来源来自生物质的热解/燃烧。在最近的2010年四英里峡谷大火中，我们还测量了加利福尼亚州洛杉矶市区和科罗拉多州博尔德市环境空气中HNCO的混合比率，最高可达200 pptv(按体积计)。此外，我们对HNCO在水中的溶解度的测量表明，HNCO在生理pH下解离，是高度可溶的。暴露水平>；1 ppbv为人类提供了异氰酸和氰酸根离子(NCO-)的直接来源，其水平已经认识到对健康的影响：动脉粥样硬化、白内障和类风湿性关节炎，通过蛋白质氨基甲基化的机制。除了野地火灾和城市来源外，我们还观察到烟草烟雾中的HNCO，据报道，HNCO来自煤炭的低温燃烧，以及作为尿素选择性催化还原(SCR)系统的副产品，这些系统正在逐步推广，以控制美国和欧盟的道路柴油NOx排放。考虑到燃烧生物质或使用烟草的人口目前的暴露水平，随着地区气候变暖和干燥，生物质燃烧排放预计会增加，以及计划增加柴油SCR控制，我们必须了解这种HNCO暴露的程度和影响。
We measured isocyanic acid (HNCO) in laboratory biomass fires at levels up to 600 parts per billion by volume (ppbv), demonstrating that it has a significant source from pyrolysis/combustion of biomass. We also measured HNCO at mixing ratios up to 200 pptv (parts-per-trillion by volume) in ambient air in urban Los Angeles, CA, and in Boulder, CO, during the recent 2010 Fourmile Canyon fire. Further, our measurements of aqueous solubility show that HNCO is highly soluble, as it dissociates at physiological pH. Exposure levels >1 ppbv provide a direct source of isocyanic acid and cyanate ion (NCO-) to humans at levels that have recognized health effects: atherosclerosis, cataracts, and rheumatoid arthritis, through the mechanism of protein carbamylation. In addition to the wildland fire and urban sources, we observed HNCO in tobacco smoke, HNCO has been reported from the low-temperature combustion of coal, and as a by-product of urea-selective catalytic reduction (SCR) systems that are being phased-in to control on-road diesel NOx emissions in the United States and the European Union. Given the current levels of exposure in populations that burn biomass or use tobacco, the expected growth in biomass burning emissions with warmer, drier regional climates, and planned increase in diesel SCR controls, it is imperative that we understand the extent and effects of this HNCO exposure.