With the increasing frequency and intensity of wildfires becoming more extreme and destructive globally, the health risks associated with smoke inhalation intensify. Climate change is a crucial factor that worsens these disasters, projecting a worsening scenario in the coming years.
These major fire events leave a trail of devastation, endangering lives and forcing the evacuation of homes and businesses. However, one of the main health hazards is the smoke produced, which can have harmful effects on the body, reaching the lungs, heart and brain. Experts say that, fortunately, there are preventative measures that people can take to protect themselves.
How smoke from forest fires harms the body
Smoke from forest fires contains a multitude of chemical substances that form during combustion, as explained by Sara Adar, professor of epidemiology at the University of Michigan. Among the most worrying components are tiny particles known as particulate matter 2.5 (PM2.5).
These particles are less than 2.5 micrometers in diameter — approximately 28 times smaller than the width of a human hair — and have the ability to lodge in the internal membranes of the nose, mouth and eyes. In the short term, exposure to these particles causes irritation and other symptoms, such as burning eyes, runny nose and cough, which can appear immediately. Individuals with skin conditions like eczema may also experience worsening of their symptoms.
Over a longer period, PM2.5 particles are small enough to be inhaled deep into the lungs, causing additional damage to the body, especially after being absorbed into the bloodstream. For example, they can trigger inflammation that worsens pre-existing respiratory conditions, such as asthma or chronic obstructive pulmonary disease (COPD). This reaction can occur immediately or within two days after exposure to wildfire smoke, according to Dr. Stephanie Lovinsky-Desir, associate professor of pediatrics and environmental health sciences at Columbia University in New York.
People with these respiratory conditions may experience greater difficulty breathing due to high levels of exposure to PM2.5, and in severe cases, may require hospitalization, Adar said. Studies have also shown that PM2.5 can irritate the heart through the bloodstream, leading to an increased risk of emergency room visits for heart attacks and coronary heart disease within 24 hours of exposure to dense wildfire smoke.
Additionally, PM2.5 can impact various aspects of cognition, such as memory, attention and learning, possibly by inducing inflammation in the central nervous system and hindering communication between neurons. Research has indicated that prolonged exposure to wildfire smoke — over a period of three years — is associated with an increased risk of developing dementia. Another study of wildfires in Oregon found that more than two weeks of exposure to intense smoke can increase the likelihood of reports of mental health symptoms, including anxiety and depression. This research supports a growing body of evidence that suggests that particle pollution may increase the risk of mental health problems.
Practical measures to protect yourself from smoke inhalation
The first step to protecting yourself from wildfire smoke is to avoid exposure as much as possible, as recommended by Lovinsky-Desir. This means leaving the area if you are in an evacuation zone, staying indoors with windows closed as much as possible, and when traveling by car, keeping the windows up.
The use of household air purifiers, especially those equipped with filters capable of retaining fine particles, can also be quite effective, said the expert. If you don’t have an air purifier, conventional air conditioners can also offer some help with air filtration, she added.
Individuals with pre-existing lung conditions or those who care for people with these conditions should ensure they have the necessary medications on hand to avoid helpless situations in the event of an emergency. On days with high levels of air pollution, physical exercise should preferably be carried out in closed places, such as gyms, suggested Adar. And if it is unavoidable to go out for some reason, wearing a mask can help reduce the risk of health impacts caused by pollutants. N95 respirators, for example, are effective in reducing exposure to PM2.5, as long as they are used correctly.
It is crucial that the face mask fits snugly to your face to ensure its effectiveness. The California Department of Health, for example, offers guidance on how to check your mask for proper fit.
