Associations between microvascular function and short-term exposure to traffic-related air pollution and particulate matter oxidative potential

Environmental Health

Research

Constantinos Sioutas¹  Sina Hasheminassab¹  Payam Pakbin¹  Ralph J. Delfino²  Tomas Tjoa²  Xian Zhang²  Norbert Staimer²  Daniel L. Gillen³  Martin M. Shafer⁴  James J. Schauer⁴  John Longhurst⁵ 

[1] Department of Civil and Environmental Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, USA;Department of Epidemiology, School of Medicine, University of California, Irvine, Irvine 224 Irvine Hall, 92617-7555, Irvine, CA, USA;Department of Statistics, School of Information and Computer Sciences, University of California, Irvine, Irvine, CA, USA;Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, WI, USA;Susan Samueli Center for Integrative Medicine, and Cardiology Division, Department of Medicine, School of Medicine, University of California, Irvine, Irvine, CA, USA;

关键词: Microvascular function;    Air pollution;    Oxidative potential;    Particulate matter components;   

DOI  :  10.1186/s12940-016-0157-5

 received in 2015-11-20, accepted in 2016-06-08,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundShort-term exposure to ambient air pollution has been associated with acute increases in cardiovascular hospitalization and mortality. However, causative chemical components and underlying pathophysiological mechanisms remain to be clarified. We hypothesized that endothelial dysfunction would be associated with mobile-source (traffic) air pollution and that pollutant components with higher oxidative potential to generate reactive oxygen species (ROS) would have stronger associations.MethodsWe carried out a cohort panel study in 93 elderly non-smoking adults living in the Los Angeles metropolitan area, during July 2012-February 2014. Microvascular function, represented by reactive hyperemia index (RHI), was measured weekly for up to 12 weeks (N = 845). Air pollutant data included daily data from regional air-monitoring stations, five-day average PM chemical components and oxidative potential in three PM size-fractions, and weekly personal nitrogen oxides (NOx). Linear mixed-effect models estimated adjusted changes in microvascular function with exposure.ResultsRHI was inversely associated with traffic-related pollutants such as ambient PM2.5 black carbon (BC), NOx, and carbon monoxide (CO). An interquartile range change increase (1.06 μg/m3) in 5-day average BC was associated with decreased RHI, −0.093 (95 % CI: −0.151, −0.035). RHI was inversely associated with other mobile-source components/tracers (polycyclic aromatic hydrocarbons, elemental carbon, and hopanes), and PM oxidative potential as quantified in two independent assays (dithiothreitol and in vitro macrophage ROS) in accumulation and ultrafine PM, and transition metals.ConclusionsOur findings suggest that short-term exposures to traffic-related air pollutants with high oxidative potential are major components contributing to microvascular dysfunction.

【 授权许可】

CC BY   
© The Author(s). 2016