Health Impact Analysis of Wildfire Smoke‐PM 2.5 in Canada (2019–2023)

Key findings from this study

• The study found that wildfire-PM2.5 exposure caused between 660 and 5,400 annual premature deaths from chronic exposure alone during 2019-2023, with economic costs ranging from $6.4 billion to $52 billion per year.
• The researchers report that over 80% of Canada's population experienced average seasonal wildfire-PM2.5 exposure of at least 1.0 μg/m³, resulting in approximately 1,900 attributable deaths annually on a 2013-2023 baseline.
• The authors demonstrate that wildfire smoke health impacts varied substantially across geography and time, requiring spatially and temporally resolved exposure assessment for accurate burden estimation.

Overview

This analysis quantifies health impacts and economic costs attributable to wildfire-PM2.5 exposure across Canada from 2019 to 2023. Air quality modeling estimated both acute and chronic disease burden, identifying substantial geographic and temporal variation in exposure. The study also extended analysis to a 2013-2023 baseline, establishing long-term population exposure patterns and mortality attributable to wildfire smoke.

Methods and approach

The researchers conducted air quality modeling to map seasonal wildfire-PM2.5 exposure across Canadian geography during 2019-2023. Health impact and economic valuation estimates incorporated exposure-response relationships to characterize both acute (immediate) and chronic (sustained) cardiorespiratory outcomes. A separate modeling effort extended the temporal window to 2013-2023 to establish decadal exposure patterns and attributable mortality.

Results

Annual premature deaths attributable to acute wildfire-PM2.5 exposure ranged from 49 to 400 deaths (2019-2023), while chronic exposure produced 660 to 5,400 deaths annually. Associated economic valuations spanned $550 million to $4.4 billion for acute health impacts and $6.4 billion to $52 billion for chronic impacts per year. Non-fatal cardiorespiratory outcomes accompanied these mortality estimates.

Over the extended 2013-2023 period, average annual seasonal wildfire-PM2.5 exposure exceeded 1.0 μg/m³ for more than 80% of the Canadian population. This longer timeframe yielded approximately 1,900 attributable premature deaths annually with a total economic valuation of $18 billion per year. Exposure exhibited substantial geographic clustering and seasonal concentration patterns.

Implications

Wildfire smoke represents a substantial and growing contributor to Canadian air pollution burdens, producing measurable population-level mortality and economic losses that warrant policy attention. The magnitude of health impacts—particularly chronic exposure effects accumulating over years—indicates that climate-driven increases in wildfire frequency will amplify future disease and economic costs unless mitigation strategies are implemented.

Regional heterogeneity in exposure and burden suggests that targeted public health and air quality management interventions should account for geographic vulnerability patterns. Inclusion of wildfire-PM2.5 health impacts in regulatory air quality standards and health impact assessments may improve resource allocation for vulnerable populations.

Scope and limitations

This summary is based on the study abstract and available metadata. It does not include a full analysis of the complete paper, supplementary materials, or underlying datasets unless explicitly stated. Findings should be interpreted in the context of the original publication.