Dataset Information

Air pollution and acute respiratory response in a panel of asthmatic children along the U.S.-Mexico border.

ABSTRACT:

Background

Concerns regarding the health impact of urban air pollution on asthmatic children are pronounced along the U.S.-Mexico border because of rapid population growth near busy border highways and roads.

Objectives

We conducted the first binational study of the impacts of air pollution on asthmatic children in Ciudad Juarez, Mexico, and El Paso, Texas, USA, and compared different exposure metrics to assess acute respiratory response.

Methods

We recruited 58 asthmatic children from two schools in Ciudad Juarez and two schools in El Paso. A marker of airway inflammation [exhaled nitric oxide (eNO)], respiratory symptom surveys, and pollutant measurements (indoor and outdoor 48-hr size-fractionated particulate matter, 48-hr black carbon, and 96-hr nitrogen dioxide) were collected at each school for 16 weeks. We examined associations between the pollutants and respiratory response using generalized linear mixed models.

Results

We observed small but consistent associations between eNO and numerous pollutant metrics, with estimated increases in eNO ranging from 1% to 3% per interquartile range increase in pollutant concentrations. Effect estimates from models using school-based concentrations were generally stronger than corresponding estimates based on concentrations from ambient air monitors. Both traffic-related and non-traffic-related particles were typically more robust predictors of eNO than was nitrogen dioxide, for which associations were highly sensitive to model specification. Associations differed significantly across the four school-based cohorts, consistent with heterogeneity in pollutant concentrations and cohort characteristics. Models examining respiratory symptoms were consistent with the null.

Conclusions

The results indicate adverse effects of air pollution on the subclinical respiratory health of asthmatic children in this region and provide preliminary support for the use of air pollution monitors close to schools to track exposure and potential health risk in this population.

SUBMITTER: Sarnat SE

PROVIDER: S-EPMC3295334 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Publications

Air pollution and acute respiratory response in a panel of asthmatic children along the U.S.-Mexico border.

Sarnat Stefanie Ebelt SE Raysoni Amit U AU Li Wen-Whai WW Holguin Fernando F Johnson Brent A BA Flores Luevano Silvia S Garcia Jose Humberto JH Sarnat Jeremy A JA

Environmental health perspectives 20110906 3

<h4>Background</h4>Concerns regarding the health impact of urban air pollution on asthmatic children are pronounced along the U.S.-Mexico border because of rapid population growth near busy border highways and roads.<h4>Objectives</h4>We conducted the first binational study of the impacts of air pollution on asthmatic children in Ciudad Juarez, Mexico, and El Paso, Texas, USA, and compared different exposure metrics to assess acute respiratory response.<h4>Methods</h4>We recruited 58 asthmatic c ...[more]

PMID: 21896396

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Dataset Information

Air pollution and acute respiratory response in a panel of asthmatic children along the U.S.-Mexico border.

Background

Objectives

Methods

Results

Conclusions

Publications

Air pollution and acute respiratory response in a panel of asthmatic children along the U.S.-Mexico border.

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