TUESDAY, Oct. 22, 2002 (HealthDayNews) -- Pollution from wood-burning stoves and gas and kerosene heaters may aggravate airway trouble in babies.
A new study of 890 infants in Connecticut and Virginia showed these secondary heat sources significantly raised the risk of wheezing and coughing in babies exposed to them in their first winter. These heaters can release fine particles as well as carbon monoxide and nitric dioxide gases, all of which irritate the lungs. Portable gas heaters are often poorly vented and spew these irritants back into the room.
The researchers didn't find a link between fireplaces and early respiratory problems, although that may be because infants weren't exposed to fires for very long. They report their findings in the latest issue of the American Journal of Respiratory and Critical Care Medicine.
Elizabeth W. Triche, a Yale University epidemiologist and leader of the study, says gas space heaters appear to be the "worst actors" among the secondary warmers for triggering breathing woes in babies.
Overall, nearly 90 percent of infants in the study had at least one bout of coughing and 33 percent had wheezing fits in their first winter. Every eight-hour increase in exposure to a gas space heater bumped up the risk of wheezing 25 percent. Wood stoves increased total coughing days, while kerosene heaters increased the bouts of coughing, though the effects were smaller than that of gas heaters.
Triche's group tried to account for a range of factors that affect a baby's risk of breathing problems, including gender -- boys are more likely than girls to have asthma as young children -- and the income, education level and smoking status of the parents. They also controlled for when in the year a child was born.
Extreme cold can trigger coughing and other airway trouble, and it's likely that the secondary heating devices were running in frigid weather. However, Triche says families that didn't use a secondary heater while others were running one tended to have fewer episodes of wheezing and coughing.
Use of a secondary heat source was relatively uncommon. A quarter of mothers in the study said they used their fireplace at least once during their infant's first winter and 17 percent used a wood stove. One in six, or 18 percent, had a kerosene heater going at least once, while only 3 percent said they'd used a gas space heater.
Roughly four in 10 mothers in the study reported having allergies, and 9 percent said they'd been formally diagnosed with asthma.
Asthma expert Dr. Linda C. Ford calls the latest work "a wonderful first step." However, she cautions it's not clear the study was showing a link between heating sources and asthma rather than breathing difficulties from other causes. "Not every bout of wheezing is asthma," says Ford, a spokeswoman for the American Academy of Allergy, Asthma and Immunology.
Triche is now looking at the impact of secondary heaters on the respiratory health of the mothers in the study. The results of that analysis will be coming out soon, she says.
What To Do
For more on asthma and home pollutants, try the U.S. Environmental Protection Agency or the American Academy of Allergy, Asthma and Immunology.
