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Wildland Fire Research: Health Effects Research

Larger and more intense wildfires are creating the potential for greater smoke production and chronic exposures in the U.S., particularly in the West. Wildfires increase air pollution in surrounding areas and can affect regional air quality.

The effects of smoke from wildfires can range from eye and respiratory tract irritation to more serious disorders, including reduced lung function, bronchitis, exacerbation of asthma and heart failure, and premature death. Children, pregnant women, and the elderly are especially vulnerable to smoke exposure. Emissions from wildfires are known to cause increased visits to hospitals and clinics by those exposed to smoke.

It is important to more fully understand the human health effects associated with short- and long-term exposures to smoke from wildfires as well as prescribed fires, referred together as wildland fires. Research is being conducted to advance understanding of the health effects from different types of fires as well as combustion phases. Researchers want to know:

  • What is the full extent of health effects from smoke exposure?
  • Who is most at risk?
  • Are there differences in health effects from different wildfire fuel types or combustion phases (burning versus flaming)?
  • What strategies and approaches are most effective in protecting public health?
  • What are the environmental, social and economic impacts of wildfire emissions?

Ongoing Research Highlights

  • A novel laboratory combustion system provides the capability to control components of fire conditions and smoke that may affect health. Animal toxicology studies are ongoing to determine if there are differences between how wildland fire smoke and typical urban air pollution impacts health. An important element of these studies is to determine whether different types of tree species and different phases of combustion (flaming to smoldering) have different health impacts.
  • Animal toxicology studies are under way to explore the physiological mechanisms of action resulting from smoke exposure to better understand what happens in the body that results in severe lung and heart health problems.
  • Studies are examining the public health impacts of fine particle pollution from wild and prescribed fires using ambient measurements and multi-year photochemical model estimates of emissions.
  • Researchers are investigating the impacts of historical and future wildfires on air quality, public health, and environmental management in the Rocky Mountains Region under various climate change scenarios and population growth patterns. The research is supported by a STAR grant on Particulate Matter and Related Pollutants in a Changing World.
  • Smoke emissions can have wider impacts outside the immediate fire area. A social science focus is providing EPA insights into the health and economic costs from changes in air quality. This societal burden is calculated in terms of incidence and cost of visits to emergency departments, hospital admissions, and loss of productivity, school absences and other similar outcomes.
    • Studies are underway to examine how public health messaging influences behavioral choices for those exposed to wildland fire smoke. 
    • A crowdsourcing study, in conjunction with the development of a smartphone app – SmokeSense– is evaluating public health communication during smoke episodes to assess the magnitude of health outcomes. The results can be used to both estimate the economic value associated with avoiding these health outcomes and examine how health risk communication strategies affect behavior and reduce public health burdens during smoke episodes.
    • Studies are being conducted to ascertain whether weatherized households have a protective effect in keeping out outdoor air pollution from wildfire smoke. Researchers are comparing health outcomes for weatherized and non-weatherized homes during wildfire season in Colorado. The research is supported by a STAR grant on Indoor Air and Climate Change.