Primary Menu

Education, Presentation, Publication

Funding & Recognition

Multi-Day Wildfire Smoke Exposure Thresholds & Distributions for an Oregon Health Impacts Study

Semester: Summer 2024


Presentation description

Wildfire smoke has drastically impacted air quality in Oregon. Recent years have seen the most severe wildfire seasons in modern history, and fires are expected to become larger and more extreme due to climate change. Fine particulate matter (PM2.5) from wildfire smoke poses significant respiratory and cardiovascular health risks, increasing the burden on healthcare systems. Few studies have focused on the duration of exposure to smoke PM2.5, particularly among children and different demographic groups. Utilizing daily census tract-level smoke PM2.5 data from 2006 to 2020, we defined high smoke days as those with a daily average smoke PM2.5 exceeding 15 µg/m³, and medium smoke days as those with 9-15 µg/m³. The threshold of 15 µg/m³ corresponds to the World Health Organization (WHO) guideline that states 24-hour average exposures should not exceed this concentration more than 3-4 days per year. The values of 9 and 15 µg/m³ are consistent with Doubleday et al. (2020), where 15 µg/m³ is the 99th percentile of PM2.5 concentrations across two relatively smoke-free years in Washington state. Across 834 Oregon census tracts from 2006 to 2020, we identified 25,317 total smoke events (defined as one or more consecutive days with smoke PM2.5 ≥ 9 µg/m³ in a single census tract). Several census tracts experienced over 60 events and 300 total event days individually. Over 60% of these days exceeded the high threshold, predominantly occurring from 2016 to 2020. Long-term events (7+ days) had a greater fraction of high threshold days than shorter events, with the longest event lasting 40 days. Additionally, over 900 events exceeded a cumulative smoke PM2.5 concentration of 1000 µg/m³. These findings will be used in a case-crossover study using Oregon patient-level hospitalization data from 2012 to 2020. The study aims to investigate the associations between the duration of smoke PM2.5 exposure and various hospitalizations among different age and demographic groups.

Presenter Name: Justin Hassel
Presentation Type: Poster
Presentation Format: In Person
Presentation #10
College: Mines & Earth Sciences
School / Department: Atmospheric Sciences
Research Mentor: Gannet Hallar
Time: 10:00 AM
Physical Location or Zoom link:

Dumke