Department of Horticulture, 23 Plant Science, Cornell University, Ithaca, NY 14853, USA.
Environ Pollut. 2011 Aug-Sep;159(8-9):2016-27. doi: 10.1016/j.envpol.2011.02.033. Epub 2011 Mar 22.
We monitored curbside airborne particulate matter (PM) concentrations and its proinflammatory capacity during 3 weekends when vehicle traffic was excluded from Park. Ave., New York City. Fine PM concentration peaked in the morning regardless of traffic while ultrafine PM was 58% lower during mornings without traffic. Ultrafine PM concentration varied linearly with traffic flow, while fine PM spiked sharply in response to random traffic events that were weakly correlated with the traffic signal cycle. Ultrafine PM concentrations decayed exponentially with distance from a cross street with unrestricted traffic flow, reaching background levels within 100 m of the source. IL-6 induction was typically highest on Friday afternoons but showed no clear relationship to the presence of traffic. The coarse fraction (>2.5 μm) had the greatest intrinsic inflammatory capacity, suggesting that coarse PM still warrants attention even as the research focus is shifting to nano-particles.
我们在纽约市公园大道（Park Ave.）周末禁止车辆通行期间，监测了路边空气中的颗粒物（PM）浓度及其促炎能力。细颗粒物（PM2.5）浓度无论是否有交通均在早晨达到峰值，而无交通时超细颗粒物（PM0.1）浓度则低 58%。超细颗粒物浓度与交通流量呈线性关系，而细颗粒物则对与交通信号灯周期弱相关的随机交通事件急剧增加。超细颗粒物浓度在距不受限制的车流的十字路口 100 米范围内呈指数衰减，达到背景水平。白细胞介素 6（IL-6）诱导通常在周五下午最高，但与交通的存在没有明显关系。粗颗粒（>2.5 μm）具有最大的固有炎症能力，这表明即使研究重点正在转向纳米颗粒，粗颗粒 PM 仍值得关注。
