NCT06749093

Health Effects of Wood Smoke and Traffic-Related Air Pollution Exposures: a Necessary Comparison

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 48 (estimated)
• Sponsor: University of British Columbia · Academic / Other
• Sex: All
• Age: 19 Years – 40 Years
• Healthy volunteers: Accepted

Summary

Accumulating evidence demonstrates that breathing air pollutants leads to devastating increases in sickness and death worldwide over time. However, there is little data comparing the effects of different types of air pollution on health. In Canada, traffic-related air pollution and wood smoke (wildfires and wood burning for heating) are very common air pollutants. This study aims to safely complete a controlled human exposure study to test how these air pollution types acutely affect health.

Detailed description

Healthy adult participants (total 48; 24 of each biological sex assigned at birth) will breathe filtered air (control), wood smoke (WS), diesel exhaust (DE), and DE plus WS (DEWS) each for 2 hours, with 4 weeks between each exposure (washout). Before and after each exposure, participants will answer questions, perform breathing tests, and give blood samples. At 24 hours after each exposure, participants will undergo a bronchoscopy to collect samples from their lungs. The study will look at what (if any) are the differences between breathing in fresh air (filtered air - FA) or polluted air containing either wood smoke (WS), diesel exhaust (DE) or diesel exhaust plus wood smoke (DEWS). The research team will use wood smoke generated from pine wood, since it is one of the most common types of wood found in Western Canadian forests where forest fires occur. The investigators will evaluate multiple endpoints as detailed in the Outcome Measures section. For each applicable endpoint, the investigators will evaluate stratified analyses and effect modification by biological sex, participant age, gene score, and microbiomes.

Conditions

• Healthy Individuals
• Allergic Rhinitis

Interventions

Type	Name	Description
OTHER	Filtered Air (FA)	Exposure to HEPA filtered air, as a control
OTHER	Wood Smoke (WS)	Wood smoke (WS) standardized to 300µg/m³ of particulate matter with a diameter of 2.5 micrometers or less (PM2.5).
OTHER	Diesel Exhaust (DE)	Diesel exhaust (DE) standardized to 300µg/m³ of particulate matter with a diameter of 2.5 micrometers or less (PM2.5).
OTHER	Diesel Exhaust and Wood Smoke (DEWS)	Combined diesel exhaust and wood smoke standardized to 300µg/m³ of particulate matter with a diameter of 2.5 micrometers or less (PM2.5).

Timeline

• Start date: 2025-07-01
• Primary completion: 2026-12-31
• Completion: 2029-12-31
• First posted: 2024-12-27
• Last updated: 2024-12-27

Locations

1 site across 1 country: Canada