A participatory study of indoor environment quality in homes of children and youth in Kanehsatake First Nation.

Indoor air quality is an important determinant for the health of children and youth, but the conditions within Indigenous communities are understudied. We collaborated with Kanehsatake First Nation in Quebec, Canada, to address this gap using a community-based participatory research approach. Levels of key indoor air indicators, including particulate matter (PM), CO, and relative humidity, were measured in 31 randomly selected households between June 2021 and January 2022.

High-resolution spatial and spatiotemporal modelling of air pollution using fixed site and mobile monitoring in a Canadian city.

The development of high-resolution spatial and spatiotemporal models of air pollutants is essential for exposure science and epidemiological applications. While fixed-site sampling has conventionally provided input data for statistical predictive models, the evolving mobile monitoring method offers improved spatial resolution, ideal for measuring pollutants with high spatial variability such as ultrafine particles (UFP). The Quebec Air Pollution Exposure and Epidemiology (QAPEE) study measured and modelled the spatial and spatiotemporal distributions of understudied pollutants, such as UFPs, black carbon (BC), and brown carbon (BrC), along with fine particulate matter (PM), nitrogen dioxide (NO), and ozone (O) in Quebec City, Canada.

Indoor air quality in remote first nations communities in Ontario, Canada.

A recent study of the health of Indigenous children in four First Nations Communities in remote northwestern Ontario found that 21% of children had been admitted to hospital for respiratory infections before age 2 years. Here we report a detailed analysis of the housing conditions in these communities. We employed a variety of statistical methods, including linear regression, mixed models, and logistic regression, to assess the correlations between housing conditions and loadings of biocontaminants (dust mite allergens, fungal glucan, and endotoxin) and indoor concentrations of PM2.

Daily Summer Temperatures and Hospitalization for Acute Cardiovascular Events: Impact of Outdoor PM 2.5 Oxidative Potential on Observed Associations Across Canada.

Background: Oxidative stress plays an important role in the health impacts of both outdoor fine particulate air pollution (PM 2.5 ) and thermal stress. However, it is not clear how the oxidative potential of PM 2.

Randomized Cross-Over Study of In-Vehicle Cabin Air Filtration, Air Pollution Exposure, and Acute Changes to Heart Rate Variability, Saliva Cortisol, and Cognitive Function.

To determine how traffic-related air pollution (TRAP) exposures affect commuter health, and whether cabin air filtration (CAF) can mitigate exposures, we conducted a cross-over study of 48 adults exposed to TRAP during two commutes with and without CAF. Measurements included particulate air pollutants (PM, black carbon [BC], ultrafine particles [UFPs]), volatile organic compounds, and nitrogen dioxide. We measured participants' heart rate variability (HRV), saliva cortisol, and cognitive function.

Long-term Exposure to Oxidant Gases and Mortality: Effect Modification by PM 2.5 Transition Metals and Oxidative Potential.

Background: Populations are simultaneously exposed to outdoor concentrations of oxidant gases (i.e., O 3 and NO 2 ) and fine particulate air pollution (PM 2.

Air Pollution and Pediatric Respiratory Hospitalizations: Effect Modification by Particle Constituents and Oxidative Potential.

Outdoor particulate and gaseous air pollutants impair respiratory health in children, and these associations may be influenced by particle composition. To examine whether associations between short-term variations in fine particulate air pollution, oxidant gases, and respiratory hospitalizations in children are modified by particle constituents (metals and sulfur) or oxidative potential. We conducted a case-crossover study of 10,500 children (0-17 years of age) across Canada.

Housing conditions and respiratory morbidity in Indigenous children in remote communities in Northwestern Ontario, Canada.

Background: Rates of lower respiratory tract infection (LRTI) among First Nations (FN) children living in Canada are elevated. We aimed to quantify indoor environmental quality (IEQ) in the homes of FN children in isolated communities and evaluate any associations with respiratory morbidity.

Methods: We performed a cross-sectional evaluation of 98 FN children (81 with complete data) aged 3 years or younger, living in 4 FN communities in the Sioux Lookout region of Northern Ontario.

Microplastics and nanoplastics science: collecting and characterizing airborne microplastics in fine particulate matter.

Microplastic (MP) pollution in the environment is increasing, leading to growing concerns about human exposures and the subsequent impact on health. Although marine MP research has received significant attention in recent years, only a few studies have attempted characterization of MP in air and examined the MP uptake and influence inhalation on human health. Moreover, the methods used for MP characterization in the marine environment require further optimization to be applicable to MP in the air.

Association of Sulfur, Transition Metals, and the Oxidative Potential of Outdoor with Acute Cardiovascular Events: A Case-Crossover Study of Canadian Adults.

Background: We do not currently understand how spatiotemporal variations in the composition of fine particulate air pollution [fine particulate matter with aerodynamic diameter ()] affects population health risks. However, recent evidence suggests that joint concentrations of transition metals and sulfate may influence the oxidative potential (OP) of and associated health impacts.

Objectives: The purpose of the study was to evaluate how of transition metals/OP and sulfur content in outdoor influence associations with acute cardiovascular events.

Aerosol SARS-CoV-2 in hospitals and long-term care homes during the COVID-19 pandemic.

Background: Few studies have quantified aerosol concentrations of SARS-CoV-2 in hospitals and long-term care homes, and fewer still have examined samples for viability. This information is needed to clarify transmission risks beyond close contact.

Methods: We deployed particulate air samplers in rooms with COVID-19 positive patients in hospital ward and ICU rooms, rooms in long-term care homes experiencing outbreaks, and a correctional facility experiencing an outbreak.

Impacts of Subway System Modifications on Air Quality in Subway Platforms and Trains.

Subway PM can be substantially sourced from the operation of the system itself. Improvements in subway air quality may be possible by examining the potential to reduce these emissions. To this end, PM was measured on the trains and station platforms of the Toronto subway system.

Predicting Spatial Variations in Multiple Measures of Oxidative Burden for Outdoor Fine Particulate Air Pollution across Canada.

Fine particulate air pollution (PM) is a leading contributor to the overall global burden of disease. Traditionally, outdoor PM has been characterized using mass concentrations which treat all particles as equally harmful. Oxidative potential (OP) (per μg) and oxidative burden (OB) (per m) are complementary metrics that estimate the ability of PM to cause oxidative stress, which is an important mechanism in air pollution health effects.

Air pollution and retinal vessel diameter and blood pressure in school-aged children in a region impacted by residential biomass burning.

Little is known about the early-life cardiovascular health impacts of fine particulate air pollution (PM) and oxidant gases. A repeated-measures panel study was used to evaluate associations between outdoor PM and the combined oxidant capacity of O and NO (using a redox-weighted average, O) and retinal vessel diameter and blood pressure in children living in a region impacted by residential biomass burning. A median of 6 retinal vessel and blood pressure measurements were collected from 64 children (ages 4-12 years), for a total of 344 retinal measurements and 432 blood pressure measurements.

Air quality in Canadian port cities after regulation of low-sulphur marine fuel in the North American Emissions Control Area.

Large marine vessels have historically used high-sulphur (S) residual fuel oil (RFO), with substantial airborne releases of sulphur dioxide (SO₂) and fine particulate matter (PM) enriched in vanadium (V), nickel (Ni) and other air pollutants. To address marine shipping air pollution, Canada and the United States have jointly implemented a North American Emissions Control Area (NA ECA) within which ships are regulated to use lower-sulphur marine fuel or equivalent SO scrubbers (i.e.

Personal exposures to traffic-related air pollution in three Canadian bus transit systems: the Urban Transportation Exposure Study.

Background: Exposure to traffic-related air pollution (TRAP) is associated with increased incidence of several cardiopulmonary diseases. The elevated TRAP exposures of commuting environments can result in significant contributions to daily exposures.

Objectives: To assess the personal TRAP exposures (UFPs, BC, PM, and PM) of the bus transit systems of Toronto, Ottawa, and Vancouver, Canada.

Within-City Spatial Variations in Multiple Measures of PM Oxidative Potential in Toronto, Canada.

Few studies have characterized within-city spatial variations in the oxidative potential of fine particulate air pollution (PM). In this study, we evaluated multiple measures of PM oxidative potential across Toronto, Canada (2016-2017), including glutathione/ascorbate-related oxidative potential (OP and OP) and dithiothreitol depletion (OP). Integrated 2-week samples were collected from 67 sites in summer and 42 sites in winter.

Are cell phones an indicator of personal exposure to organophosphate flame retardants and plasticizers?

Background: Exposure to organophosphate ester (OPE) flame retardants and plasticizers is widespread and is of concern due to their toxicity.

Objectives: To investigate relationships between and within OPE concentrations in air, dust, hands, electronic product wipes and urinary metabolites with the goal of identifying product sources and exposure pathways.

Methods: Women in Toronto and Ottawa, Canada, provided a urine sample, two sets of hand wipes, access to their homes for air and dust sampling, and completed a questionnaire.

Spatial variations in the estimated production of reactive oxygen species in the epithelial lung lining fluid by iron and copper in fine particulate air pollution.

Background: Certain metals may play an important role in the adverse health effects of fine particulate air pollution (PM), but few models are available to predict spatial variations in these pollutants.

Methods: We conducted large-scale air monitoring campaigns during summer 2016 and winter 2017 in Toronto, Canada, to characterize spatial variations in iron (Fe) and copper (Cu) concentrations in PM. Information on Fe and Cu concentrations at each site was paired with a kinetic multilayer model of surface and bulk chemistry in the lung epithelial lining fluid to estimate the possible impact of these metals on the production of reactive oxygen species (ROS) in exposed populations.

Cardiorespiratory Effects of Air Pollution in a Panel Study of Winter Outdoor Physical Activity in Older Adults.

Objective: The aim of this study was to assess cardiorespiratory effects of air pollution in older adults exercising outdoors in winter.

Methods: Adults 55 years of age and older completed daily measurements of blood pressure, peak expiratory flow and oximetry, and weekly measurements of heart rate variability, endothelial function, spirometry, fraction of exhaled nitric oxide and urinary oxidative stress markers, before and after outdoor exercise, for 10 weeks. Data were analyzed using linear mixed effect models.

Metro Commuter Exposures to Particulate Air Pollution and PM-Associated Elements in Three Canadian Cities: The Urban Transportation Exposure Study.

System-representative commuter air pollution exposure data were collected for the metro systems of Toronto, Montreal, and Vancouver, Canada. Pollutants measured included PM (PM = particulate matter), PM, ultrafine particles, black carbon, and the elemental composition of PM. Sampling over three weeks was conducted in summer and winter for each city and covered each system on a daily basis.

Biomass Burning as a Source of Ambient Fine Particulate Air Pollution and Acute Myocardial Infarction.

Background: Biomass burning is an important source of ambient fine particulate air pollution (PM2.5) in many regions of the world.

Methods: We conducted a time-stratified case-crossover study of ambient PM2.

The impact of a landfill fire on ambient air quality in the north: A case study in Iqaluit, Canada.

A large landfill fire occurred in Iqaluit, Canada in spring/summer 2014. Air quality data were collected to characterize emissions as well as potential threats to public health. Criteria pollutants were monitored (PM2.

In-vehicle exposures to particulate air pollution in Canadian metropolitan areas: the urban transportation exposure study.

Commuters may be exposed to increased levels of traffic-related air pollution owing to close proximity to traffic-emissions. We collected in-vehicle and roof-top air pollution measurements over 238 commutes in Montreal, Toronto, and Vancouver, Canada between 2010 and 2013. Voice recordings were used to collect real-time information on traffic density and the presence of diesel vehicles and multivariable linear regression models were used to estimate the impact of these factors on in-vehicle pollutant concentrations (and indoor/outdoor ratios) along with parameters for road type, land use, and meteorology.

Impact of microenvironments and personal activities on personal PM2.5 exposures among asthmatic children.

Personal activity patterns have often been suggested as a source of unexplained variability when comparing personal particulate matter (PM2.5) exposure to modeled data using central site or microenvironmental data. To characterize the effect of personal activity patterns on asthmatic children's personal PM2.