As North America rebounds from some of the worst air quality in decades as a result of wildfires, one of the largest and most comprehensive research into the long-term health implications of smoke exposure raises serious concerns about the Canadian wildfires’ long-term health impact.
A 10 μg/m3 increase in wildfire-related PM2.5 exposure was linked with a 0.4 % higher risk of all-cause and nonaccidental death, as well as a 0.5 % increased chance of dying from neoplasms, according to the study. On June 8, at the height of the wildfire pollution, PM2.5 values reached 460 μg/m3.
The study, headed by Monash University in Australia and published in the Journal of Hazardous Materials, is the first to look at the association between long-term exposure to wildfire-related fine particulate matter (PM2.5) and mortality over an 11-year period.
The study also discovered no significant relationships between wildfire-related PM2.5 exposure and death from cardiovascular, respiratory, or mental diseases.
To date, investigations into the health effects of wildfire-related PM2.5 exposure have shown an elevated risk of all-cause, cardiovascular, and respiratory mortality; however, most of the evidence has focused on short-term effects, according to lead researcher Associate Professor Shanshan Li from the School of Public Health and Preventive Medicine.
We aimed to estimate the long-term impacts of wildfire-related PM2.5 exposure on mortality in adults using a large-scale national cohort database from the UK Biobank. To the best of our knowledge, this is the first population-based prospective cohort study to quantify the associations between long-term exposure to wildfire-related PM2.5 and mortality.
Shanshan Li, Associate Professor, School of Public Health and Preventive Medicine, Monash University
The data originated from a subset of the UK Biobank, which included 492,394 people enrolled from 2004 to 2010, who were followed up on a regular basis in the UK, acquiring biological samples and lifestyle surveys, which were then related to their health-related records. The scientists subsequently extracted mortality data, including the underlying (main) cause of death and date of death, and linked it to wildfire-related PM2.5 exposure 1 to 5 years before death.
Associate Professor Li’s findings “show that wildfire-related PM2.5 exposure has long-lasting adverse impacts on all-cause, nonaccidental, and neoplasm mortality.”
Given the recent pollution levels in North America caused by the Canadian wildfires, our study linking long-term exposure to wildfire-related PM2.5 and mortality suggest that further research is urgently needed to provide more scientific evidence on this topic.
Shanshan Li, Associate Professor, School of Public Health and Preventive Medicine, Monash University
Journal Reference:
Gao, Y., et al. (2023). Association between long-term exposure to wildfire-related PM2.5 and mortality: A longitudinal analysis of the UK Biobank. Journal of Hazardous Materials. doi.org/10.1016/j.jhazmat.2023.131779.