Fine Particulate Matter and Polycyclic Aromatic Hydrocarbon Concentration Patterns in Roxbury, Massachusetts: A Community-Based GIS Analysis

Abstract

ArticlesGiven an elevated prevalence of respiratory disease and density of pollution sources, residents of Roxbury, Massachusetts, have been interested in better understanding their exposures to air pollution. To determine whether local transportation sources contribute significantly to exposures, we conducted a community-based pilot investigation to measure concentrations of fine particulate matter (particulate matter < 2.5 µm; PM 2.5 ) and particle-bound polycyclic aromatic hydrocarbons (PAHs) in Roxbury in the summer of 1999. Community members carried portable monitors on the streets in a 1-mile radius around a large bus terminal to create a geographic information system (GIS) map of concentrations and gathered data on site characteristics that could predict ambient concentrations. Both PM 2.5 and PAH concentrations were greater during morning rush hours and on weekdays. In linear mixed-effects regressions controlling for temporal autocorrelation, PAH concentrations were significantly higher with closer proximity to the bus terminal (p < 0.05), and both pollutants were elevated, but not statistically significantly so, on bus routes. Regressions on a subset of measurements for which detailed site characteristics were gathered showed higher concentrations of both pollutants on roads reported to have heavy bus traffic. Although a more comprehensive monitoring protocol would be needed to develop robust predictive functions for air pollution, our study demonstrates that pollution patterns in an urban area can be characterized with limited monitoring equipment and that university-community partnerships can yield relevant exposure information. Key words: community-based research, fine particulate matter, geographic information system, personal exposure, polycyclic aromatic hydrocarbons, transportation. Environ Health Perspect 109:341-347 (2001). [Online 8 March 2001] http://ehpnet1.niehs.nih.gov/docs/2001/109p341-347levy/abstract.html

Influence of traffic patterns on particulate matter and polycyclic aromatic hydrocarbon concentrations in Roxbury, Massachusetts

“…Roxbury is a neighborhood that contains multiple bus routes as well as bus and truck depots, indicating the likelihood of significant diesel traffic and related emissions, and spatial pollution patterns have been analyzed there in the past (Levy et al, 2001).…”

“…We used identical instrumentation as in our recent exposure assessment studies in Boston (Levy et al, 2001(Levy et al, , 2002, to ensure comparability of findings. We measured PM 2.5 concentrations using a DustTrak Model 8520 (TSI, Minneapolis, MN, USA), a laser photometer fitted with an impactor to exclude larger particles.…”

“…Similarly, polycyclic aromatic hydrocarbon (PAH) concentrations in an urban center differed by a factor of three between measurements on a street and in a park, with traffic contributing an estimated 80% of ambient concentrations (Nielsen, 1996). Urban PAH concentrations have also been linked with traffic volume, with minimal concentrations during low traffic and higher concentrations during rush hour (Levy et al, 2001). Ultrafine particle concentrations have been strongly correlated with traffic patterns, with particle number concentrations a factor of five greater at peak traffic periods than at night (Ruuskanen et al, 2001) and a factor of seven greater within 15 m of the road compared with average urban exposure levels (Hitchins et al, 2000).…”

Characterizing Urban Traffic Exposures Using Transportation Planning Tools: An Illustrated Methodology for Health Researchers

“…TAZ-level traffic density and emissions estimates for NOx, CO, and volatile organic compounds (VOCs) reflect automobile and truck traffic but not buses or commuter lines, which may be an important omission particularly in areas with a high density of bus lines or commuter rails. 12 Some MPOs develop estimates of the contribution of these sources to overall emissions, but at the least, any use of TAZ data should discuss this limitation.…”

“…The scale of traffic-related health assessments has ranged from large nationwide cohorts utilizing area-wide monitoring data or national databases 4,5 to more localized studies of specific regions, 6 air basins, 7,8 cities, [9][10][11] and neighborhoods [12][13][14] using air quality data of specific traffic-related pollutants collected to represent a more localized or even personal scale. Whether examining regional trends or local conditions, each scale of assessment faces the task of appropriately integrating spatial and temporal data regarding traffic impacts with available demographic and health outcome data to assess what has been termed "geographies of risk."…”