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Home > Health Topics > Healthy Outlook > Reduce Indoor Asthma Triggers this Winter

Reduce Indoor Asthma Triggers this Winter

Published by Contra Costa Times
Posted on Wednesday, November 23, 2011
By Dr. David Pepper

With cold weather and the winter ahead, many families make fires to keep warm. Before you light the kindling, there are a few health impacts on your family you should consider. That nice wood burning smell may be harming your family and neighbors who have respiratory allergies.

Wood fires create a substantial amount of smoke, which is the visible portion of particulate matter. These small particles of carbon-rich material are small enough to pass through nose into the throat and into lungs. Wood smoke also contains many toxic substances including benzene and dioxin. The amount produced by fireplaces is substantial.

In many areas, wood smoke accounts for 30% to 70% of the particulate matter in winter air. To make it worse, this material is created very close to where we live and sleep.

Most healthy people will not experience immediate side effects; however, breathing these particles can shorten your lifespan and send our most vulnerable residents to the emergency room with respiratory problems. These microscopic particles can damage cells, exacerbate asthma and cause lung and heart disease. For asthmatic children, breathing wood smoke can lead to immediate harm, including asthma attacks and respiratory distress. For older people it may even bring on a heart attack.

A recent study by the California Air Resources Board reported that wood smoke can cause a 10 percent increase of hospital admissions for respiratory problems among children, who are at most risk since their lungs are still developing.

In Contra Costa County, there are an estimated 100,000 residents who suffer from asthma, including many children and elderly who struggle to breathe from emphysema, lung cancer and other respiratory illnesses. When these people have to breathe wood smoke pollution, they struggle even more.

And it doesn't take much to trigger symptoms. One fireplace or wood-burning stove can produce levels of smoke in a neighborhood that exceed federal air quality standards and affect all the neighbors, with up to 70% of smoke from chimneys re-entering neighboring residences.

Two years ago, the Bay Area Air Quality Management District adopted a wood-burning regulation that bans wood-burning when air quality is poor, but also regulates visible emissions. For more information, visit

Are these health impacts really worth the ambience of a fire when cleaner burning options are available? If you do burn, there are steps you can take to significantly reduce the smoke and toxics produced by your fireplace or woodstove:

  • build a hot fire with clean, dry wood
  • make sure the fire receives plenty of air by limiting the use of air dampers
  • consider use of Duraflame or other cleaner-burning "logs"
  • consider installing a pellet or wood stove if you make fires regularly

Hopefully, after understanding the harm caused by wood smoke pollution, you will think twice before snuggling up to that fireplace.

For more information about asthma triggers, visit

Dr. Pepper practices family medicine at the Martinez Health Center.

Also of interest:

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