The study, which followed a group of asthmatic children in Baltimore, Md., is among the first to examine the effects of indoor particulate matter pollution. The results are published in the February 2009 edition of the journal Environmental Health Perspectives.
Particulate matter is an airborne mixture of solid particles and liquid droplets. The solid particles come in numerous shapes and sizes and may be composed of different chemical components. Fine particles measure 2.5 microns or less in size (approximately 1/30th the diameter of a human hair) and can penetrate deep into the body’s respiratory system. Coarse particles fall between 2.5 and 10 microns in diameter.
These larger particles can also enter the respiratory system and can be produced indoors through activities such as cooking and dusting. The U.S. Environmental Protection Agency (EPA) regulates outdoor levels of fine particle pollution, but does not have a standard for coarse particle pollution. There are no regulations for indoor pollution.
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. Environmental monitoring equipment was used to measure the air in the child’s bedroom for over three three-day intervals. Air measurements were taken at the beginning of the study, after 3 months and again after 6 months. Ninety-one percent of the children who participated in the study were African-American, from lower socioeconomic backgrounds, and spent most of their time indoors.
“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.
Additional authors of “In Home Particle Concentrations and Childhood Asthma Morbidity” are Elizabeth C. Matsui, Nadia N. Hansel, D’Ann Williams, Jean Curtin-Brosnan and Peyton Eggleston.
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.
Tim Parsons | EurekAlert!
Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign
Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences