EPA Science Inventory

CHARACTERIZATION OF A SPATIAL GRADIENT OF NITROGEN DIOXIDE ACROSS A UNITED STATES-MEXICO BORDER CITY DURING WINTER

Citation:

Gonzales, M, C. Qualls, E E. Hudgens, AND L Neas. CHARACTERIZATION OF A SPATIAL GRADIENT OF NITROGEN DIOXIDE ACROSS A UNITED STATES-MEXICO BORDER CITY DURING WINTER. Elsevier (ed.), SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier Science Ltd, New York, NY, 337(1-3):163-173, (2005).

Description:

A gradient of ambient nitrogen dioxide (NO2) concentration is demonstrated across metropolitan El Paso, Texas (USA), a city located on the international border between the United States and Mexico. Integrated measurements of NO2 were collected over seven days at 20 elementary schools and four air quality monitoring stations located throughout the city during typical winter atmospheric conditions. Replicate passive monitors were co-located with chemiluminescence analyzers at the monitoring stations for two consecutive seven-day periods. The passive measurements correlated with the analyzer measurements (R2 = 0.74) with precision of 2.5 + 2.2 ppb. Nitrogen dioxide concentrations ranged from 11.0 to 37.5 ppb (mean 20.6 + 7.1 ppb). In a multivariate regression model, the site elevation, and distances to a main highway and to an international port of entry from Mexico explained 81% of the variance in the passive measurements. The results of this pilot study indicate that proximity to vehicle-related sources of NO2 and atmospheric mixing height are key predictors for future, more detailed assessments of vehicle-related air pollution exposure in the El Paso region.

Purpose/Objective:

to study the gradient of ambient nitrogen dioxide (NO2) concentration

Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Start Date: 01/20/2005
Completion Date: 01/20/2005
Record Last Revised: 10/24/2008
Record Created: 12/08/2004
Record Released: 12/08/2004
OMB Category: Other
Record ID: 104818

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LAB

HUMAN STUDIES DIVISION

EPIDEMIOLOGY AND BIOMARKERS BRANCH