Changes in lung function and airway inflammation among asthmatic children residing in a woodsmoke-impacted urban area.
ABSTRACT Fine particulate matter (PM(2.5)) is associated with respiratory effects, and asthmatic children are especially sensitive. Preliminary evidence suggests that combustion-derived particles play an important role. Our objective was to evaluate effect estimates from different PM(2.5) exposure metrics in relation to airway inflammation and lung function among children residing in woodsmoke-impacted areas of Seattle. Nineteen children (ages 6-13 yr) with asthma were monitored during the heating season. We measured 24-h outdoor and personal concentrations of PM(2.5) and light-absorbing carbon (LAC). Levoglucosan (LG), a marker of woodsmoke, was also measured outdoors. We partitioned PM(2.5) exposure into its ambient-generated (E(ag)) and nonambient (E(na)) components. These exposure metrics were evaluated in relation to daily changes in exhaled nitric oxide (FE(NO)), a marker of airway inflammation, and four lung function measures: midexpiratory flow (MEF), peak expiratory flow (PEF), forced expiratory volume in the first second (FEV(1)), and forced vital capacity (FVC). E(ag), but not E(na), was correlated with combustion markers. Significant associations with respiratory health were seen only among participants not using inhaled corticosteroids. Increases in FE(NO) were associated with personal PM(2.5), personal LAC, and E(ag) but not with ambient PM(2.5) or its combustion markers. In contrast, MEF and PEF decrements were associated with ambient PM(2.5), its combustion markers, and E(ag), but not with personal PM(2.5) or personal LAC. FEV(1) was associated only with ambient LG. Our results suggest that lung function may be especially sensitive to the combustion-generated component of ambient PM(2.5), whereas airway inflammation may be more closely related to some other constituent of the ambient PM(2.5) mixture.
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ABSTRACT: With 40% of the World's population relying on solid fuel, household air pollution (HAP) represents a major preventable risk factor for COPD. Meta-analyses have confirmed this relationship, however constituent studies are observational with virtually none measuring exposure directly.Environmental Health Perspectives 11/2014; DOI:10.1289/ehp.1408200 · 7.03 Impact Factor
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ABSTRACT: To investigate whether short-term systemic effects of wood smoke occurred in atopic subjects after experimental wood smoke exposures. A double-blind climate chamber study was conducted on 20 healthy atopic subjects with exposures to filtered air and wood smoke. Pneumoproteins, coagulation and adhesion factors, and cytokines were measured. Heart rate was monitored with pulse monitors. Data were analyzed with mixed models. Few differences in the outcomes were observed. Plasma tissue factor remained elevated during filtered air exposure (P = 0.002). P-selectin declined independent of exposure (P = 0.0006). Interleukin-6 increased after filtered air (P = 0.03). The study confirmed previous observations among nonatopics of limited changes after a 3-hour wood smoke exposure.This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially.Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine 01/2014; 56(2). DOI:10.1097/JOM.0000000000000067 · 1.80 Impact Factor
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ABSTRACT: The role of non-invasive methods in the investigation of acute effects of traffic related air pollution is not clearly established. We evaluated the usefulness of non invasive biomarkers in detecting acute air pollution effects according to the age of participants, the disease status, their sensitivity compared with lung function tests, and their specificity for a type of pollutant.Search terms lead to 535 titles, among them 128 had potentially relevant abstracts. Sixtynine full papers were reviewed, while 59 articles were excluded since they did not meet the selection criteria.Methods used to assess short term effects of air pollution included analysis of nasal lavage (NAL) for the upper airways, and induced sputum (IS), exhaled breath condensate (EBC), exhaled nitric oxide (FeNO) for central and lower airways.There is strong evidence that FeNO evaluation is useful independently from subject age, while IS analysis is suitable almost for adults. Biomarker changes are generally observed upon pollutant exposure irrespective of the disease status of the participants. None of the biomarkers identified are specific for a type of pollutant exposure. Based on experimental exposure studies, there is moderate evidence that IS analysis is more sensitive than lung function tests, whereas this is not the case for biomarkers obtained by NAL or EBC. Cells and some cytokines (IL-6, IL-8 and MPO) have been measured both in the upper respiratory tract (NAL) and in the lower airways (IS). Overall, the response to traffic exposure seems different in the two compartments.In conclusion, this survey of current literature displays the complexity of this research field, highlights the significance of short-term studies on traffic pollution and gives important tips when planning studies to detect acute respiratory effects of air pollution in a non-invasive way.This article is protected by copyright. All rights reserved.Clinical & Experimental Allergy 07/2014; 44(9). DOI:10.1111/cea.12373 · 4.32 Impact Factor