| Can We Identify Sources of Fine Particles Responsible for Exercise-Induced Ischemia on Days with Elevated Air Pollution? The ULTRA Study Timo Lanki,1 Jeroen J. de Hartog,2 Joachim Heinrich,3 Gerard Hoek,2 Nicole A.H. Janssen,4 Annette Peters,3 Matthias Stölzel,3 Kirsi L. Timonen,5,6 Marko Vallius,1 Esko Vanninen,5,6 and Juha Pekkanen1,6 1Environmental Epidemiology Unit, National Public Health Institute, Kuopio, Finland; 2Environmental and Occupational Health Division, Institute for Risk Assessment Sciences, Utrecht University, the Netherlands; 3Institute of Epidemiology, GSF-National Research Center for Environment and Health, Neuherberg, Germany; 4Center for Environmental Health Research, National Institute for Public Health and the Environment, Bilthoven, the Netherlands; 5Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, Kuopio, Finland; 6University of Kuopio, Kuopio, Finland Abstract
Epidemiologic studies have shown that ambient particulate matter (PM) has adverse effects on cardiovascular health. Effective mitigation of the health effects requires identification of the most harmful PM sources. The objective of our study was to evaluate relative effects of fine PM [aerodynamic diameter ≤ 2.5 µm (PM2.5) ] from different sources on exercise-induced ischemia. We collected daily outdoor PM2.5 samples between autumn 1998 and spring 1999 in Helsinki, Finland. The mass of PM2.5 was apportioned between five sources. Forty-five elderly nonsmoking persons with stable coronary heart disease visited a clinic biweekly for submaximal exercise testing, during which the occurrence of ST segment depressions was recorded. Levels of PM2.5 originating from local traffic and long-range transport were associated with ST segment depressions > 0.1 mV, with odds ratios at 2-day lag of 1.53 [95% confidence interval (CI) , 1.19-1.97] and 1.11 (95% CI, 1.02-1.20) per 1 µg/m3, respectively. In multipollutant models, where we used indicator elements for sources instead of source-specific PM2.5, only absorbance (elemental carbon) , an indicator of local traffic and other combustion, was associated with ST segment depressions. Our results suggest that the PM fraction originating from combustion processes, notably traffic, exacerbates ischemic heart diseases associated with PM mass. Key words: air pollution, cardiovascular disease, elements, soot, vehicle emission. Environ Health Perspect 114:655-660 (2006) . doi:10.1289/ehp.8578 available via http://dx.doi.org/ [Online 13 January 2006]
Address correspondence to T. Lanki, Environmental Epidemiology Unit, National Public Health Institute, P.O. Box 95, 70701 Kuopio, Finland. Telephone: 358-17-201-326. Fax: 358-17-201-480. E-mail: timo.lanki@ktl.fi The ULTRA project was funded by the European Union (ENV4-CT97-0568) . The project coordinator (National Public Health Institute, Kuopio, Finland) also received funding from the Academy of Finland. The reporting was financially supported by the Centre of Excellence Programme 2002-2007 of the Academy of Finland (contract 53307) and the National Technology Fund (TEKES contract 40715/01) . The authors declare they have no competing financial interests. Received 11 August 2005 ; accepted 12 January 2006.
The full version of this article is available for free in HTML or PDF formats. |
