Impacts of Fine Particulate Matter From Wildfire Smoke on Respiratory and Cardiovascular Health in California

Alexandra Heaney; Jennifer D Stowell; Jia Coco Liu; Rupa Basu; Miriam Marlier; Patrick Kinney

doi:10.1029/2021GH000578

Impacts of Fine Particulate Matter From Wildfire Smoke on Respiratory and Cardiovascular Health in California

Geohealth. 2022 Jun 3;6(6):e2021GH000578. doi: 10.1029/2021GH000578. eCollection 2022 Jun.

Authors

Alexandra Heaney¹, Jennifer D Stowell², Jia Coco Liu³, Rupa Basu⁴, Miriam Marlier⁵, Patrick Kinney²

Affiliations

¹ Division of Environmental Health Sciences School of Public Health University of California, Berkeley Berkeley CA USA.
² Department of Environmental Health School of Public Health Boston University Boston MA USA.
³ Facebook Menlo Park CA USA.
⁴ California Office of Environmental Health Hazard Assessment Air and Climate Epidemiology Section Oakland CA USA.
⁵ Department of Environmental Health Sciences University of California, Los Angeles Los Angeles CA USA.

Abstract

Increases in wildfire activity across the Western US pose a significant public health threat. While there is evidence that wildfire smoke is detrimental for respiratory health, the impacts on cardiovascular health remain unclear. This study evaluates the association between fine particulate matter (PM_2.5) from wildfire smoke and unscheduled cardiorespiratory hospital visits in California during the 2004-2009 wildfire seasons. We estimate daily mean wildfire-specific PM_2.5 with Goddard Earth Observing System-Chem, a global three-dimensional model of atmospheric chemistry, with wildfire emissions estimates from the Global Fire Emissions Database. We defined a "smoke event day" as cumulative 0-1-day lag wildfire-specific PM_2.5 ≥ 98th percentile of cumulative 0-1 lag day wildfire PM_2.5. Associations between exposure and outcomes are estimated using negative binomial regression. Results indicate that smoke event days are associated with a 3.3% (95% CI: [0.4%, 6.3%]) increase in visits for all respiratory diseases and a 10.3% (95% CI: [2.3%, 19.0%]) increase for asthma specifically. Stratifying by age, we found the largest effect for asthma among children ages 0-5 years. We observed no significant association between exposure and overall cardiovascular disease, but stratified analyses revealed increases in visits for all cardiovascular, ischemic heart disease, and heart failure among non-Hispanic white individuals and those older than 65 years. Further, we found a significant interaction between smoke event days and daily average temperature for all cardiovascular disease visits, suggesting that days with high wildfire PM_2.5 concentrations and high temperatures may pose greater risk for cardiovascular disease. These results suggest substantial increases in adverse outcomes from wildfire smoke exposure and indicate the need for improved prevention strategies and adaptations to protect vulnerable populations.

Keywords: impacts of climate change: human health; pollution: urban and regional; public health.