For the study, researchers from the Center for Childhood Asthma in the Urban Environment—a joint center of the Johns Hopkins Bloomberg School of Public Health and the Johns Hopkins School of Medicine—followed 150 asthmatic children, ages 2 to 6, for six months. "We found that substantial increases in asthma symptoms were associated both with higher indoor concentrations of fine particles and with higher indoor concentrations of coarse particles," said Meredith C. McCormack, MD, MHS, lead author of the study and an instructor with the Johns Hopkins School of Medicine.
For every 10 micrograms per cubic meter of air (ug/m3) increase in indoor coarse particle concentration, there was a 6 percent increase in the number of days of cough, wheeze, or chest tightness, after adjusting for a number of factors. For every 10 ug/m3 increase in fine particles measured indoors, there was a 7 percent increase in days of wheezing severe enough to limit speech and after adjusting for various factors, a 4 percent increase in days on which rescue medication was needed. In many cases, the level of indoor fine particle pollution measured was twice as high as the accepted standard for outdoor pollution established by the EPA.
"Children spend nearly 80 percent of their time indoors, which makes understanding the effects of indoor air very important," said co-author, Gregory B. Diette, MD, an associate professor in the School of Medicine and co-director of the Center for Childhood Asthma in the Urban Environment.
"Improving indoor air quality and lowering indoor particulate matter concentrations may provide additional means of improving asthma health, especially for children living in inner cities," added co-author, Patrick Breysse, PhD, a professor in the Johns Hopkins Bloomberg School of Public Health and co-director of the Center for Childhood Asthma in the Urban Environment.
The research was supported by National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health; the U.S. Environmental Protection Agency; and the Johns Hopkins NIEHS Center for Urban Environmental Health.
Source: Johns Hopkins University Bloomberg School of Public Health (2009, February 27). Indoor Air Pollution Increases Asthma Symptoms, Study Suggests. ScienceDaily. Retrieved June 13, 2009, from http://www.sciencedaily.com/releases/2009/02/090219101700.htm