The variability of hazardous air pollutants (HAPs) is an important factor in determining human exposure to such chemicals, and in designing HAP measurement programs.
This study has investigated the factors which contribute to HAP variability in an urban area.
Six measurement sites separated by up to 12 km collected data with 3 h time resolution to examine spatial variability within neighborhoods and between neighborhoods.
The measurements were made in Columbus, OH.
The 3 h results also were used to study temporal variability, and duplicate samples collected at each site were used to determine the component of variability attributable to the measurement process.
Hourly samples collected over 10 days at one site provided further insight into the temporal resolution needed to capture short-term peak concentrations.
Measurements at the 6 spatial sites focused on 78 chemicals.
Twenty-three of these species were found in at least 95% of the 3 h samples, and 39 chemicals were present at least 60% of the time.
The relative standard deviations for most of these 39 frequently detected chemicals was 1.0 or lower.
Variability was segmented into temporal, spatial, and measurement components.
Temporal variation was the major contributor to HAP variability for 19 of the 39 frequently detected compounds, based on the 3 h data. (...)
Mots-clés Pascal : Pollution air, Zone urbaine, Polluant, Variation spatiale, Teneur air ambiant, Variation temporelle, Composé organique volatil
Mots-clés Pascal anglais : Air pollution, Urban area, Pollutant, Spatial variation, Ambient air concentration, Time variation, Volatile organic compound
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 96-0394484
Code Inist : 001D16C04D. Création : 10/04/1997.