Increasing Wildfire Smoke from the Climate Crisis: Impacts on Asthma and Allergies

Details

• Personal Author:
  Balmes JR ; Holm SM
• Description:
  Catastrophic wildfires have been increasing around the globe, including in Australia, Chile, Indonesia, Portugal, Russia, the United States, and Canada. Over the past year alone, there have been massive fires in Canada that have blanketed major sections of North America with poor air quality because of wildfire smoke. Climate change is a major driver of the increased frequency and severity of wildfires owing to warmer temperatures, drought, and more extreme weather. Because catastrophic wildfires fueled by high winds are more difficult to suppress and there has been an increase in the population living within the wildland-urban interface (WUI), fires are overrunning neighborhoods and whole towns. The recent devastation of the town of Lahaina on Maui reminds us of the extreme danger of WUI fires. Smoke from catastrophic wildfires has also caused extended periods of poor air quality in large areas downwind. Wildfire smoke is a heterogenous mixture of carbon dioxide, carbon monoxide, nitrogen oxides, particulate matter (PM), complex hydrocarbons such as polycyclic aromatic hydrocarbons and dioxins, and irritant gases (eg, acrolein, benzene, and formaldehyde)-many of the same toxic and carcinogenic substances as found in cigarette smoke. The composition of wildfire emissions varies depending on the type of fuel, meteorologic conditions, and burning conditions. Wildfire smoke undergoes chemical transformations in the atmosphere that alter its composition as the smoke travels downwind; secondary pollutants, such as ozone and secondary organic aerosol, are also generated. When synthetic materials burn in WUI fires, even more toxic materials such as phosgene and hydrochloric acid are emitted. Fine PM (particulate matter <2.5 µm in diameter [PM2.5]) is a major toxic component of wildfire smoke and is used to assess public exposure to smoke. Concentrations of PM2.5 because of wildfire smoke have been extremely high in US cities, with a peak of 200 µg/m3 in New York City in June 2023. For reference, the health-based US Environmental Protection Agency 24-hour average air quality standard is 35 µg/m3. [Description provided by NIOSH]
• Subjects:
  Air Pollution Asthma Asthma, Occupational Climate Change Fires Hypersensitivity Occupational Health Particulate Matter Safety Wildfires
• Keywords:
  Air Pollution Allergies Author Keywords: Climate Change Climate Change Particulates PM2.5 Wildfire Smoke Wildland Fire Smoke
• ISSN:
  0091-6749
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  152
• Issue:
  5
• NIOSHTIC Number:
  nn:20069784
• Citation:
  J Allergy Clin Immunol 2023 Nov; 152(5):1081-1083
• Contact Point Address:
  John R. Balmes, MD, Department of Medicine, University of California San Francisco, Box 0843, San Francisco, CA 94143-0843
• Email:
  John.balmes@ucsf.edu
• Federal Fiscal Year:
  2024
• Performing Organization:
  University of California, Berkeley
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Journal of Allergy and Clinical Immunology
• End Date:
  20250630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:7f0f6b2edfd0e0a6155587a92f1426ea92900f898bba3b5ae6f6fc19587a0a21ca1a7f43b79ee011e6f5c08b6410b094381a6c6e030bd9e24485699ee9e605b0
• Download URL:
  https://stacks.cdc.gov/view/cdc/208140/cdc_208140_DS1.pdf
• File Type:
  [PDF - 501.86 KB ]