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Assessment of spatial variation of fugitive dust sources, particularly road dust track-out from industrial sites and its subsequent re-suspension is difficult with fixed air quality monitoring stations given their sparse distribution and the highly localized nature of road dust. Mobile monitoring was employed to measure levels of road dust in the industrial area of the City of Hamilton, Ontario, Canada. Results of this monitoring were used in a Fugitive Dust Control workshop held for local stakeholders, where fugitive dust control solutions were presented. After the workshop, the City of Hamilton and cooperative industrial groups executed enhanced street cleaning and individual industries and facilities performed on-site control activities. Post-workshop mobile air monitoring was performed for comparison to the initial values to determine effectiveness of these approaches. A regression model testing the difference pre- and post-workshop yielded a statistically significant difference in PM(10) measurements demonstrating improvement. The average value of PM(10) prior to the workshop was 114 μg/m(3). Post-workshop the average value dropped to 73 μg/m(3)., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

We investigated the spatial and topographic effects of temperature inversions on air quality in the industrial city of Hamilton, located at the western tip of Lake Ontario, Canada. The city is divided by a 90-m high topographic scarp, the Niagara Escarpment, and dissected by valleys which open towards Lake Ontario. Temperature inversions occur frequently in the cooler seasons, exacerbating the impact of emissions from industry and traffic. This study used pollution data gathered from mobile monitoring surveys conducted over a 3-year period, to investigate whether the effects of the inversions varied across the city. Temperature inversions were identified with vertical temperature data from a meteorological tower located within the study area. We divided the study area into an upper and lower zone separated by the Escarpment and further into six zones, based on location with respect to the Escarpment and industrial and residential areas, to explore variations across the city. The results identified clear differences in the responses of nitrogen dioxide (NO(2)) and fine particulate matter (PM2.5) to temperature inversions, based on the topographic and spatial criteria. We found that pollution levels increased as the inversion strengthened, in the lower city. However, the results also suggested that temperature inversions identified in the lower city were not necessarily experienced in the upper city with the same intensity. Further, pollution levels in the upper city appeared to decrease as the inversion deepened in the lower city, probably because of an associated change in prevailing wind direction and lower wind speeds, leading to decreased long-range transport of pollutants., (Copyright 2010 Elsevier B.V. All rights reserved.)

Air pollution in urban centres is increasing, with burgeoning population and increased traffic and industry. The detrimental impact on population health has been the focus of many epidemiological studies. Some cities are fortunate to have one, or at most a few, sparsely spaced fixed air quality monitors, which provide much needed daily data. However, fixed monitors do not accurately depict the spatial distribution of air pollution over the extent of an urban area nor can they target areas for focused surveys. We have used mobile monitoring to improve spatial coverage of pollution concentrations over the city of Hamilton, Ontario and to enhance our knowledge of the short-term bursts of pollution to which the population is exposed. Mobile surveys have been carried out in the city of Hamilton, Ontario, Canada since 2005. Results for two pollutants, oxides of nitrogen (NO(x)) representing traffic sources, and sulfur dioxide (SO2) representing industry sources, are presented. The data demonstrate very high levels of NO(x) exceeding 600 ppb, near major highways with SO2 levels up to 249 ppb near industrial sources. Both values significantly exceed the hourly maxima recorded by fixed monitors. The results also highlight the effect of wind direction on SO2 and NO(x) levels, and the affected population in each scenario.

This paper examines the change in air pollutant concentrations between 2005 and 2010 occurring in the City of Hamilton, Ontario, Canada. After analysis of stationary air pollutant concentration data, we analyze mobile air pollutant concentration data. Air pollutants included in the analysis are CO, PM, SO, NO, NO, and NO. Stationary monitoring indicates a continuous reduction in air pollutant concentrations. Stationary monitors only cover a small spatial extent of Hamilton. Mobile monitoring of air pollutant concentrations, averaged over census tract boundaries, indicates both improvement and decline in air quality. These improvements and declines in air quality are spatially clustered throughout Hamilton. Mobile data indicated significant decline in median pollutant concentration for CO, SO, PM, and NO; but significant increase for NO and NO. Air quality change in Hamilton is spatially heterogeneous, and is not captured based on the current stationary monitoring network. Coupling of mobile and stationary air pollutant concentration monitoring provides a more accurate spatial assessment of local air quality. [ABSTRACT FROM AUTHOR]