Wildfire Research Confirms Health Hazards of Peat Fire Smoke
An EPA-led study finds associations between peat wildfire smoke and increased emergency room visits.
It may be tempting to breathe a sigh of relief if a rampant wildfire strays wide of your home. But don't breathe too deep; even if you can avoid the flames, you are not out of harm's way.
A research paper recently published by EPA shows that peat wildfire smoke can increase risk of serious respiratory and cardiovascular effects. This paper is the first to show an association between wildfire smoke and increased emergency room visits for symptoms of heart failure.
Peat is partially decomposed vegetable matter commonly found in wetland areas. Peat wildfires can smolder in the ground for months and are notoriously difficult to extinguish.
"A peat fire differs significantly from a forest fire or grassland fire where the fuel is timber or grasses," says Wayne Cascio, director of EPA's Environmental Public Health Division. "Peat fires burn at lower temperature, produce more smoke, and generate chemicals that are more irritating to the eyes and airways."
On June 1, 2008 a lightning strike in coastal North Carolina (NC) sparked a prolific wildfire. This smoldering conflagration burned for three months before it was considered 90% contained. Having scorched over 40,000 acres of land, it was not until January 5, 2009 that the peat wildfire was officially declared "out" according to the U.S. Fish and Wildlife Service, which manages Pocosin Lakes National Wildlife Refuge, where 60% of the fire's devastation occurred.
More threatening than the physical destruction of the lingering fire was the enormous smoke plume that hovered over much of eastern NC. "The lower temperature of the peat fire produces plumes of smoke that remain close to the ground and severely affect nearby communities," says Cascio.
Consequently, EPA researchers led a study examining the health risks associated with peat wildfire smoke from the 2008 fire. Using satellite imaging, researchers were able to identify counties most severely impacted by the peat fire's smoke pollution. Researchers then collected emergency room (ER) records from those smoke-affected counties for dates of highest smoke exposure and for dates of little or no smoke exposure.
Data were also collected from neighboring counties that experienced much less smoke pollution over the same period of time. By comparing the ER records of smoke-affected days to those of smoke-free days, scientists found a marked increase in respiratory and cardiovascular ER visits in the heavily smoke-affected counties.
Research statistics show that in smoke affected counties, ER visits during heavy smoke exposure days relative to smokeless days increased by:
- 73% for Chronic Obstructive Pulmonary Disease (COPD)
- 65% for asthma
- 59% for pneumonia and bronchitis
- 37% for symptoms of heart failure
.A paper describing the results of this study was published June 27, 2011 by Environmental Health Perspectives.
As a mix of decomposing plant matter and soil, burning peat emits different chemicals than burning trees or grass, and the health effects of those chemicals have been poorly understood. This is the first study of a naturally occurring peat fire in the U.S. and the first known study to show that exposure to a peat fire can cause both respiratory and cardiovascular effects.
"One finding unique to this study is the observation that ER visits for heart failure increased," Cascio points out. "Previous wildfires have either shown no effect or a very weak positive effect, so our observation that ER visits for heart failure increased by 37% was surprising."
The study results also suggest that certain groups of people – aged adults and those with pre-existing lung and heart problems – are more susceptible to the adverse affects of peat wildfire smoke.
The publication of this research comes at a particularly relevant time as peat wildfires have been ravaging coastal North Carolina since early May, 2011. Scientists hope that this research will be useful in guiding public health officials and the local population to be aware of their local air quality and to take appropriate actions to safeguard their health.
"The public is rightfully concerned about the potential for adverse health effects of the current peat fire in eastern NC," says Cascio. "This study can provide a context to educate the public on the actual risk to the population and what steps can and should be taken to lessen the health risk."
The significant findings of this research may lead to further research into modeling weather and wind patterns to predict the location of a wildfire smoke plume in advance of extreme smoke exposure. With this type of technology, susceptible populations would be forewarned of hazardous air conditions and could take action to limit exposure and decrease adverse health impacts.