Health News

Smoke Danger From California Wildfires

Oct. 24, 2007 (Burbank, Calif.) -- Skies in Southern California have an eerie, dirty look as smoke spews from the numerous wildfires that began raging Sunday and may still be days from containment.

Where there is smoke, there are health hazards, experts warn, perhaps even for healthy residents living miles from the fire zones.

"Even as far away as 20 miles, you can see some unhealthy effects of the fire damage," says Zab Mosenifar, MD, a pulmonologist and director of the Cedars-Sinai Medical Center Women's Guild Pulmonary Disease Institute in Los Angeles. A Malibu resident, Mosenifar awoke Tuesday morning to find his yard and family cars covered in ash as the fire continued to blaze not far from his beach house.

Residents in fire zones and nearby areas are urged  to take precautions, pay attention to symptoms that may be related to smoke exposure, and check the air quality in their immediate vicinity before spending any time outdoors, especially when exercising, Mosenifar and other experts tell WebMD.

Particle Size Determines Risk

Smoke from wildfires includes small particles of ash and other substances, water vapor, and gases such as carbon monoxide. The sizes of these particles affect the body differently, Mosenifar tells WebMD. Larger particles generally can't get into the nose and upper respiratory tract, he says, although they might irritate the eyes, outside of the nose, mouth, and skin.

But smaller particles -- those so tiny they are about 30 times smaller than the diameter of a human hair --can easily get into your respiratory system, he says. And there they can cause irritation in the lungs, runny noses, burning eyes, and aggravate existing heart and lung problems such as emphysema, asthma, and congestive heart failure.

While the bigger, heavier particles drop to the earth as the smoke billows out from the fire, the smaller particles can travel some distances, he says, depending on winds, temperatures, and other factors.  "If you live 15 or 20 miles from a fire, you are still exposed to particles, but the particle size is smaller," he says.

How to Gauge the Smoke Danger

Use your senses to gauge the level of pollution from smoke exposure, says Frank Gilliland, MD, PhD, professor of preventive medicine at the University of Southern California Keck School of Medicine, who studied the health effects of the 2003 California wildfires on children. "We tell people if they can smell smoke, it's at very high levels. They should use their own senses to tell them what they should be doing [in terms of outdoor activity]."

If people feel eye or throat irritation while outdoors, Gilliland tells WebMD, "they ought to alter their activity  [and exercise indoors] until the levels abate."

Paying attention to symptoms -- and taking precautions such as exercising indoors -- is advised for a period of time after the fire is out, he adds. Those living in the California wildfire zones are probably wise to take precautions for two weeks, he says, depending on how quickly the smoke dissipates.