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BACKGROUND AND AIM: A growing body of evidence indicates that exposure to air pollution affects cognitive performance; however, few studies have assessed this in the context of repeated measures wi...

BACKGROUND AND AIM: There is increasing evidence that air pollution exposure adversely impacts cognitive health. While wildfire smoke is a pollutant of growing concern, there is little evidence to ...

Background: Exposure to fine particulate matter (PM2.5) during wildfire seasons has been associated with adverse health outcomes. Previous studies have focused on daily exposure, but PM2.5 levels in smoke events can vary considerably within 1 d. Objectives: We aimed to assess the immediate and lagged relationship between sub-daily exposure to PM2.5 and acute health outcomes during wildfire seasons in British Columbia. Methods: We used a time-stratified case-crossover study design to evaluate the association between modeled hourly PM2.5 and ambulance dispatches during wildfire seasons from 2010 to 2015. Distributed lag nonlinear models were used to estimate the lag-specific and cumulative odds ratios (ORs) at lags from 1 to 48 h. We examined the relationship for all dispatches and dispatches related to respiratory, circulatory, and diabetic conditions, identified by codes for ambulance dispatch (AD), paramedic assessment (PA) or hospital diagnosis (HD). Results: Increased respiratory health outcomes were observed within 1 h of exposure to a 10-μg/m3 increase in PM2.5. The 48-h cumulative OR [95% confidence interval (CI)] was 1.038 (1.009, 1.067) for the AD code Breathing Problems and 1.098 (1.013, 1.189) for PA code Asthma/COPD. The point estimates were elevated within 1 h for the PA code for Myocardial Infarction and HD codes for Ischemic Heart Disease, which had 24-h cumulative ORs of 1.104 (0.915, 1.331) and 1.069 (0.983, 1.162), respectively. The odds of Diabetic AD and PA codes increased over time to a cumulative 24-h OR of 1.075 (1.001, 1.153) and 1.104 (1.015, 1.202) respectively. Conclusions: We found increased PM2.5 during wildfire seasons was associated with some respiratory and cardiovascular outcomes within 1 h following exposure, and its association with diabetic outcomes increased over time. Cumulative effects were consistent with those reported elsewhere in the literature. These results warrant further investigation and may have implications for the appropriate time scale of public health actions. https://doi.org/10.1289/EHP5792

Background: Indoor and outdoor exposures to fine particulate matter (PM2.5) are both leading risk factors for death and disease, but collecting indoor measurements is often infeasible for large stu...

Urban greenness has been associated with a wide range of health benefits, partially due to local cooling. Several studies on these health benefits have assessed individual and population exposure to urban greenness using the Normalized Difference Vegetation Index (NDVI) from different satellite platforms. Recent comparisons between birds-eye NDVI and street-level measurements suggest that NDVI can severely misclassify individual exposure which, in turn, can bias epidemiologic effect estimates. Pedestrian video data may provide a novel source of individual, eye-level information on both indoor and outdoor exposure to vegetation. The objective of this pilot study was to examine the potential of pedestrian video data for assessing exposure to urban greenness using secondary data collected for a different study on microscale urban air temperatures. Image processing was used to extract green, yellow, and shaded pixels from ˜10 million frames of video footage collected during 40 sampling runs of 20 urban routes measuring 8–10 km each. Resulting greenness values (combined total of green, yellow, and shaded pixels) were compared with concurrent air temperatures using correlations, time series plots, and maps. Correlations ranged from -0.61 to 0.34 and were in the expected direction for 31 of 40 runs. Time series plots and overlay maps showed clear inverse relationships in many cases. Most routes originally chosen to characterize higher temperature areas had negative correlations. Flat and weakly positive relationships tended to occur when conditions were overcast or routes were closer to large waterways. Secondary data are limited for such assessments, but the methods described here are promising for future exposure assessment at the individual level and evaluation of methods applied at the population level.

There is limited evidence for short-term associations between mortality and ambient air pollution in the Middle East, and no studies examining the association between daily mortality and the air qu...

Background: Residential woodsmoke is an under-regulated source of fine particulate matter (PM2.5), often surpassing mobile and industrial emissions in rural communities in North America and elsewhe...

Increases in wildfire frequency and intensity have been observed over recent decades, and are expected to continue with climate change. Exposure to wildfire smoke has been associated with a wide ra...

Background/Aim: In recent years, many air quality monitoring programs have favoured measurement of particles less than 2.5 microns (PM2.5) over particles less than 10 microns (PM10) in light of evi...

Background/Aim: Extreme hot weather events are increasing in intensity, frequency, and duration as a consequence of climate change. As a result, hot weather mortality is a growing concern in many u...

Introduction: The AirCare vehicle inspection program began in 1992 to control tailpipe emissions within the Greater Vancouver area, Canada, and ended in 2014. Since 1992, there have been regional d...

Introduction: Little is known about ambient concentrations of volatile organic compounds (VOCs) and their spatial variability in Tehran, Iran. We aimed to characterize the spatial distribution of a...

Background: During the summer of 2003 numerous fires burned in British Columbia, Canada. Objectives: We examined the associations between respiratory and cardiovascular physician visits and hospital admissions, and three measures of smoke exposure over a 92-day study period (1 July to 30 September 2003). Methods: A population-based cohort of 281,711 residents was identified from administrative data. Spatially specific daily exposure estimates were assigned to each subject based on total measurements of particulate matter (PM) ≤ 10 μm in aerodynamic diameter (PM10) from six regulatory tapered element oscillating microbalance (TEOM) air quality monitors, smoke-related PM10 from a CALPUFF dispersion model run for the study, and a SMOKE exposure metric for plumes visible in satellite images. Logistic regression with repeated measures was used to estimate associations with each outcome. Results: The mean (± SD) exposure based on TEOM-measured PM10 was 29 ± 31 μg/m3, with an interquartile range of 14–31 μg/m3. Correlations between the TEOM, smoke, and CALPUFF metrics were moderate (0.37–0.76). Odds ratios (ORs) for a 30-μg/m3 increase in TEOM-based PM10 were 1.05 [95% confidence interval (CI), 1.03–1.06] for all respiratory physician visits, 1.16 (95% CI, 1.09–1.23) for asthma-specific visits, and 1.15 (95% CI, 1.00–1.29) for respiratory hospital admissions. Associations with cardiovascular outcomes were largely null. Conclusions: Overall we found that increases in TEOM-measured PM10 were associated with increased odds of respiratory physician visits and hospital admissions, but not with cardiovascular health outcomes. Results indicating effects of fire smoke on respiratory outcomes are consistent with previous studies, as are the null results for cardiovascular outcomes. Some agreement between TEOM and the other metrics suggests that exposure assessment tools that are independent of air quality monitoring may be useful with further refinement.

Introduction: Climate change is expected to increase the burden of waterborne acute gastrointestinal illness (AGI) due to the increased frequency and intensity of extreme precipitation events. Here...

Introduction: Land use regression (LUR) models based on measurement campaigns are frequently used to assess long-term exposure to ambient air pollution. Our aim was to develop LUR models based on f...

*Introduction:* Most excess deaths that occur during extreme hot weather events do not have natural heat recorded as an underlying or contributing cause. This makes it challenging to identify exces...

Introduction: Increased frequency and intensity of forest fires affects many regions around the world. Exposure to forest fire smoke (FFS) has been associated with a range of adverse health effects...

Background: The air quality in Tehran, Iran is poor compared with the cities in North America and Europe where land use regression (LUR) has been most frequently applied. Aims: We aimed to estimate...

Background: Exposure to wildfire smoke has been associated with increases in measures of respiratory health. Forecasts of smoke exposure can provide prospective information to support public health...

Background: While the vast majority air pollution epidemiology and risk assessment relies upon ambient surface monitoring, large segments of the population live in locations that are not well-chara...

Background: During the summer of 2009, greater Vancouver (in British Columbia, Canada) experienced several days of unusually hot temperatures. Episodes of extreme heat in other northern cities have...

Background and Aims: Vegetation fires annually release an average of approximately 2 petagrams of carbon to the atmosphere causing recurring episodes of severe regional air pollution and contributi...