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Residential wood burning can be a significant wintertime source of ambient fine particles in urban and suburban areas. We developed a statistical model to predict minute (min) levels of particles with median diameter of <1 μm (PM1) from mobile monitoring on evenings of winter weekends at different residential locations in Quebec, Canada, considering wood burning emissions. The 6 s PM1 levels were concurrently measured on 10 preselected routes travelled 3 to 24 times during the winters of 2008-2009 and 2009-2010 by vehicles equipped with a GRIMM or a dataRAM sampler and a Global Positioning System device. Route-specific and global land-use regression (LUR) models were developed using the following spatial and temporal covariates to predict 1-min-averaged PM1 levels: chimney density from property assessment data at sampling locations, PM2.5 'regional background' levels of particles with median diameter of <2.5 μm (PM2.5) and temperature and wind speed at hour of sampling, elevation at sampling locations and day of the week. In the various routes travelled, between 49% and 94% of the variability in PM1 levels was explained by the selected covariates. The effect of chimney density was not negligible in 'cottage areas.' The R2 for the global model including all routes was 0.40. This LUR is the first to predict PM1 levels in both space and time with consideration of the effects of wood burning emissions. We show that the influence of chimney density, a proxy for wood burning emissions, varies by regions and that a global model cannot be used to predict PM in regions that were not measured. Future work should consider using both survey data on wood burning intensity and information from numerical air quality forecast models, in LUR models, to improve the generalisation of the prediction of fine particulate levels. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to assess the relationships between deprivation at Quebec public schools, their proximity to polluting industries, and their exposure to industrial air emission sources including ambient fine particulate matter (PM2.5), sulphur dioxide (SO2) and nitrogen dioxide (NO2)., Methods: We obtained four indicators of school deprivation using data from the 2006 Canadian census called the low-income threshold indicator, the neighbourhood SES indicator, and the social and material deprivation indicators of Pampalon. Using proximity spatial tools, we constructed three buffers of 2.5, 5 and 7.5 km around each school and summed up total emissions of PM2.5, SO2 and NO2 for each school. Industrial air emissions were estimated using data from the 2006 Canadian National Pollutant Release Inventory. The Pearson correlations and LOESS regressions and natural log-transformed industrial air emissions were evaluated for Quebec public schools within the three buffers., Results: Of the 2189 public schools in Quebec, 608 (27.8%), 1108 (50.6%) and 1384 (63.2%) schools were located near at least one industry emitting one or more pollutants of interest in buffers of 2.5 km, 5 km and 7.5 km of schools respectively. Weak positive Pearson correlations (r) were found between log-transformed tons of industrial emissions of PM2.5, SO2 and NO2 and both the social deprivation (r = {0.23; 0.33}) and low-income threshold (r = {0.17; 0.29}) indicators in a buffer of 2.5 km. However, we found negative associations between emissions and the neighbourhood SES (r = {0.06; 0.16}) and material deprivation (r = {-0.04; 0.08}) indicators., Conclusion: Our study suggests that schools in Quebec with higher rates of socio-economic deprivation among their students may be more likely to be exposed to higher emissions of industrial air pollutants.

Objectives: 1) To describe grassroots projects aimed at the built environment and associated with active transportation on the Island of Montreal; and 2) to examine associations between the number of projects and indicators of neighbourhood material and social deprivation and the built environment., Method: We identified funding agencies and community groups conducting projects on built environments throughout the Island of Montreal. Through website consultation and a snowballing procedure, we inventoried projects that aimed at transforming built environments and that were carried out by community organizations between January 1, 2006, and November 1, 2010. We coded and validated information about project activities and created an interactive map using Geoclip software. Correlational analyses quantified associations between number of projects, neighbourhood characteristics and deprivation., Results: A total of 134 community organizations were identified, and 183 grassroots projects were inventoried. A large number of projects were aimed at increasing awareness of/improving active or public transportation (n=95), improving road safety (n=84) and enhancing neighbourhood beautification and greening (n=69). The correlation between the presence of projects and the extent of neighbourhood material deprivation was small (Kendall's t=0.26, p&lt;0.001), but in areas with greater social deprivation there were more projects (Kendall's t=0.38, p&lt;0.001). Larger numbers of projects were also associated with the presence of more extensive land-use mix (Kendall's t=0.23, p&lt;0.001) and a greater proportion of road intersections with injured pedestrians, cyclists and motor vehicle users (Kendall's t=0.43, p&lt;0.001)., Conclusion: There is significant community mobilization around built environments and active transportation. Investigations of the implementation processes and impacts are warranted.

Objective: Estimate the number of awakenings additional to spontaneous awakenings, induced by the nighttime aircraft movements at an international airport in Montreal, in the population residing nearby in 2009., Methods: Maximum sound levels (LAS,max) were derived from aircraft movements using the Integrated Noise Model 7.0b, on a 28 x 28 km grid centred on the airport and with a 0.1 x 0.1 km resolution. Outdoor LAS,max were converted to indoor LAS,max by reducing noise levels by 15 dB(A) or 21 dB(A). For all grid points, LAS,max were transformed into probabilities of additional awakening using a function developed by Basner et al. (2006). The probabilities of additional awakening were linked to estimated numbers of exposed residents for each grid location to assess the number of aircraft-noise-induced awakenings in Montreal., Results: Using a 15 dB(A) sound attenuation, 590 persons would, on average, have one or more additional awakenings per night for the year 2009. In the scenario using a 21 dB(A) sound attenuation, on average, no one would be subjected to one or more additional awakenings per night due to aircraft noise., Conclusion: Using the 2009 flight patterns, our data suggest that a small number of Montreal residents are exposed to noise levels that could induce one or more awakenings additional to spontaneous awakenings per night.

Objectives: Environmental factors associated with winter outdoor falls are poorly understood. This study describes the demographic, spatial and temporal distribution of outdoor falls that occurred in Laval and Montréal Island (Canada) in relation to meteorological conditions., Method: Data on falls, including geographic coordinates, were obtained from ambulance services (December 1, 2008 to january 31, 2009). Meteorological (temperature, precipitation levels) and land use data were used for descriptive analysis and mapping., Results: During the study period, 3270 falls required ambulance interventions, of which 960 occurred outdoors. Most people injured outdoors were under 65 years of age (59%). Mapping showed a concentration of outdoor falls in central neighbourhoods and on commercial streets in Montreal. Three episodes of excess falls, representing 47% of all outdoor falls, were preceded by rain and followed by falling temperatures, or were concomitant with freezing rain., Conclusion: Our results demonstrate for the first time the distribution of outdoor falls in a densely populated urban setting with a northern climate. To promote active transportation, it is essential to take into account the safety of pedestrian travel. Snow removal and de-icing operations in municipalities should prioritize areas with high pedestrian activity.

Objectives: Exposure to traffic-related air pollutants plays a role in several health outcomes. A large body of evidence tends to link asthma in children with traffic exposure. Increasing asthma prevalence and incidence in children in Canadian cities has been of concern for public health authorities. The following study focuses on estimating the risk of asthma prevalence attributable to residing in proximity to major roads on the Island of Montreal, Canada., Methods: Risk functions pertaining to asthma in children and residential proximity to major roads were selected from the literature and applied to Montreal. Asthma prevalence was taken from population-based studies. Population data were retrieved from Canadian census. Exposure was estimated using the proximity to major road and highway category of the Desktop Mapping Technologies Inc. database (DMTI Spatial Inc.)., Results: Based on different studies, the percentage of prevalent asthma cases attributable to residing within 50 metres of a major road or highway for children aged 2, 4 and 6 years varied between 2.4% (0-4.3), 5.6% (0.1-8.6) and 5.9% (0.1-9.0). For the 5-7 year age group residing within 75 m of a major road or highway, the percent of cases was 6.4% (2.6-9.3). For children aged 8 to 10 residing within 75 m of a highway only, the percent of cases was 0.7% (0.2-0.9)., Conclusion: These numbers represent the best crude estimates and are an indication of a possible range of cases linked to residential proximity to major roads. As there are uncertainties linked to the application of exposure-response functions, these estimates will be reassessed as new evidence is gathered through further research.