Association between exhaled breath condensate nitrate + nitrite levels with ambient coarse particle exposure in subjects with airways disease
- Sarah Manney1,
- C M Meddings2,
- R M Harrison2,12,
- A H Mansur1,
- A Karakatsani3,
- A Analitis4,
- Klea Katsouyanni4,
- D Perifanou4,
- I G Kavouras5,
- N Kotronarou5,
- J J de Hartog6,
- J Pekkanen7,8,
- K Hämeri9,
- Harry ten Brink10,
- Gerard Hoek6,
- Jon G Ayres11
- 1Department of Respiratory Medicine, Birmingham Heart of England NHS Trust, Birmingham, UK
- 2Division of Environmental Health Risk Management, University of Birmingham, Birmingham, UK
- 32nd Department of Pulmonary Medicine, “ATTIKON” University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- 4Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- 5National Observatory Athens, Institute for Environmental Research and Sustainable Development, Athens, Greece
- 6Institute for Risk Assessment Sciences, University of Utrecht, Utrecht, The Netherlands
- 7Department of Environmental Health, National Institute for Health and Welfare, Kuopio, Finland
- 8Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
- 9Department of Physics, University of Helsinki, Helsinki, Finland
- 10Energy Research Center of the Netherlands, Business Unit ECN Clean Fossil Fuels, Petten, The Netherlands
- 11Institute of Occupational and Environmental Medicine, University of Birmingham, Birmingham, UK
- 12Department of Environmental Sciences/Center of Excellence in Environmental Studies, King Abdulaziz University, Jeddah, Saudi Arabia
- Correspondence to Professor Jon G Ayres, Institute of Occupational and Environmental Medicine, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK;
Contributors SM, AHM and JGA were responsible for development of the exhaled breath condensate methodology, including the laboratory analysis of the samples. SM and JGA provided the first draft text of the paper. RMH, KK, NK, JP, HtB, KH, JGA and GH contributed to the design of the RUPIOH study and interpretation of the results. CMM, AK, DP, IGK and JJdH contributed to the conduct and design of the local studies. AA, SM and GH contributed to the statistical analysis. All authors commented on the draft text and agree with the text. Primary responsibility for the study is with JGA, SM and GH.
- Accepted 31 May 2012
- Published Online First 5 July 2012
Objectives Studies of individual inflammatory responses to exposure to air pollution are few but are important in defining the most sensitive markers in better understanding pathophysiological pathways in the lung. The goal of this study was to assess whether exposure to airborne particles is associated with oxidative stress in an epidemiological setting.
Methods The authors assessed exposure to particulate matter air pollution in four European cities in relation to levels of nitrite plus nitrate (NOx) in exhaled breath condensate (EBC) measurements in 133 subjects with asthma or chronic obstructive pulmonary disease using an EBC capture method developed for field use. In each subject, three measurements were collected. Exposure measurements included particles smaller than 10 μm (PM10), smaller than 2.5 μm (PM2.5) and particle number counts at a central site, outdoors near the subject's home and indoors.
Results There were positive and significant relationships between EBC NOx and coarse particles at the central sampling sites (increase of 20.4% (95% CI 6.1% to 36.6%) per 10 μg/m3 increase of coarse particles of the previous day) but not between EBC NOx and other particle measures. Associations tended to be stronger in subjects not taking steroid medication.
Conclusions An association was found between exposure to ambient coarse particles at central sites and EBC NOx, a marker of oxidative stress. The lack of association between PM measures more indicative of personal exposures (particularly indoor exposure) means interpretation should be cautious. However, EBC NOx may prove to be a marker of PM-induced oxidative stress in epidemiological studies.
- Air pollution
- particulate matter
- particle number concentration
- exhaled breath condensate
- oxidative stress
- exposure assessment
- general expertise
- biological monitoring
- organ system
- disease type
- lung function
- exposures and occupational groups
- occupational asthma
- mortality studies
- public health
- environmental tobacco smoke
- exposure monitoring
- time series study
- longitudinal studies
- clinical medicine
Funding European Union (grant number QLRT-2001-00452).
Competing interests None.
Patient consent Obtained.
Ethics approval Ethics approval was provided by Medical Ethical Committees in the four study centres.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement All data were available to all authors. The final data analysis files were prepared and shared by SM, JGA and GH.