Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York, USA.
Environ Health Perspect. 2010 Sep;118(9):1338-43. doi: 10.1289/ehp.0901499. Epub 2010 May 7.
Exposure to traffic-related particulate matter (PM) has been associated with adverse respiratory health outcomes in children. Diesel exhaust particles (DEPs) are a local driver of urban fine PM [aerodynamic diameter < or = 2.5 microm (PM(2.5))]; however, evidence linking ambient DEP exposure to acute respiratory symptoms is relatively sparse, and susceptibilities of urban and asthmatic children are inadequately characterized.
We examined associations of daily ambient black carbon (BC) concentrations, a DEP indicator, with daily respiratory symptoms among asthmatic and nonasthmatic adolescents in New York City (NYC) and a nearby suburban community.
BC and PM(2.5) were monitored continuously outside three NYC high schools and one suburban high school for 4-6 weeks, and daily symptom data were obtained from 249 subjects (57 asthmatics, 192 nonasthmatics) using diaries. Associations between pollutants and symptoms were characterized using multilevel generalized linear mixed models, and modification by urban residence and asthma status were examined.
Increases in BC were associated with increased wheeze, shortness of breath, and chest tightness. Multiple lags of nitrogen dioxide (NO(2)) exposure were associated with symptoms. For several symptoms, associations with BC and NO(2) were significantly larger in magnitude among urban subjects and asthmatics compared with suburban subjects and nonasthmatics, respectively. PM(2.5) was not consistently associated with increases in symptoms.
Acute exposures to traffic-related pollutants such as DEPs and/or NO(2) may contribute to increased respiratory morbidity among adolescents, and urban residents and asthmatics may be at increased risk. The findings provide support for developing additional strategies to reduce diesel emissions further, especially in populations susceptible because of environment or underlying respiratory disease.
接触与交通相关的颗粒物（PM）已被证实与儿童的呼吸道健康不良后果有关。柴油尾气颗粒（DEP）是城市细颗粒物[空气动力学直径<或=2.5 微米（PM（2.5））]的局部驱动因素；然而，将环境 DEP 暴露与急性呼吸道症状联系起来的证据相对较少，城市和哮喘儿童的易感性也没有得到充分描述。
我们研究了纽约市（NYC）和附近郊区的哮喘和非哮喘青少年中，每日环境黑碳（BC）浓度（DEP 指标）与每日呼吸道症状之间的关系。
在三所 NYC 高中和一所郊区高中外连续监测 BC 和 PM（2.5），为期 4-6 周，并通过日记从 249 名受试者（57 名哮喘患者，192 名非哮喘患者）中获得每日症状数据。使用多层广义线性混合模型描述污染物与症状之间的关系，并检查城市居住和哮喘状态的修饰作用。
BC 增加与喘息、呼吸急促和胸闷增加有关。二氧化氮（NO（2））暴露的多个滞后与症状有关。对于几种症状，与 BC 和 NO（2）的关联在城市受试者和哮喘患者中比在郊区受试者和非哮喘患者中分别显著更大。PM（2.5）与症状的增加并不一致。
交通相关污染物如 DEP 和/或 NO（2）的急性暴露可能导致青少年呼吸道发病率增加，城市居民和哮喘患者的风险可能增加。这些发现为进一步制定减少柴油排放的额外策略提供了支持，特别是在因环境或潜在呼吸道疾病而敏感的人群中。
