THURSDAY, Oct. 9, 2003 (HealthDayNews) -- Tiny air pollution particles of organic carbon and nitrogen dioxide can trigger chronic bronchitis in children with asthma.
That finding is reported in the October issue of the American Journal of Respiratory and Critical Care Medicine.
The study from 1996 through 1999 of 475 children with asthma in 12 southern California communities says organic carbon and nitrogen dioxide deserve greater attention as potential causes of chronic bronchitis in children with asthma.
It also concludes that previous studies may have underestimated the risks that air pollution poses to children with asthma.
Researchers investigated different-sized fractions of particulate organic matter, elemental carbon, nitrogen dioxide and other traffic-related pollutants and their effect on the children with asthma.
Children with a history of wheezing during the year before the study or those with allergies in the past were more likely to report symptoms of bronchitis.
Overall, the study found the children's bronchitis symptoms were associated with the yearly variability in the amount of air pollution particulate matter.
The researchers note that organic carbon accounts for almost half of the fine particulate matter in the Los Angeles air basin. Gasoline and diesel vehicle exhaust is the major source of organic carbon in southern California.
Here's where you can learn more about childhood asthma.