California Air Resources Board

SACRAMENTO - Today, the Air Resources Board heard the results of several studies that show smoke from wood fires aggravates lung and heart disease and increases the number of hospital admissions.

"Today's report to the Board underscores the need for air districts throughout the state to curtail fireplace burning when air quality is suffering," said ARB Chairman Mary Nichols. "This starkly illustrates our need to continue reducing particulate matter emissions."

At this morning's hearing, board members heard a presentation of research results that indicate exposure to wood smoke may reduce lung function and reduce the blood's ability to clot properly. In addition, wood smoke exposure may also increase substances in the body that lead to cardio-vascular and pulmonary inflammation. These health threats could be particularly dangerous to those with preexisting heart or lung disease.

ARB research staff reviewed four recent national toxicological studies in presenting today's findings to the Board. The findings support fireplace ordinances that many local air districts throughout California are implementing.

The research found that wood smoke can cause a 10 percent increase of hospital admissions for respiratory problems among children. ARB estimates that between 20 to 80 percent of ambient wintertime particulate matter is due to wood smoke. Studies have found up to 70 percent of smoke from chimneys can re-enter a home or neighboring residences.

Wood smoke consists of several pollutants, including carbon monoxide, nitrogen dioxide, particulate matter and other irritating and toxic components. California's wood smoke problem and its pollution problem in general, are compounded by the state's geography and weather. The many valleys and calm air cause the pollutants to remain at ground level rather than be swept away.

In several areas throughout California, air quality officials are restricting residential wood burning on days when particulate matter pollution is expected to be high. These and other strategies are substantially reducing wintertime peak particulate matter levels and therefore should reduce the risk of cardiovascular hospitalizations and premature deaths.