Increase in Pollution-causing Particles Cause Lung Infections in Children

Even the slightest increase in airborne fine particulate matter PM2.5 is associated with the development of acute lower respiratory infection (ALRI) in young children, suggests new study. The study is the largest till date to evaluate the association between the two factors. The study was conducted by research teams from Intermountain Healthcare, Brigham Young University and University of Utah and is published in the American Journal of Respiratory and Critical Care Medicine, an American Thoracic Society journal. PM2.5 refers to atmospheric particulate matter (PM) that have a diameter of less than 2.5 micrometers. These particles are about 3% the diameter of a human hair. They are so small that they can go into the lungs and may cause serious health problems. Forty eight percent of emissions that lead to the formation of these particulate matter are contributed by motor vehicles. Thirty nine percent of all fine particulates is from small industry and businesses such as gas stations and dry cleaners, as well as home heating. Thirteen percent is from large manufacturing.

Study Overview

The study involved more than 1,00,000 patients and is the largest to date to study the effect of increase in fine particulate matter on lung infections in children. The study also wanted to look at the same associations for older children, adolescents and adults.

The team studied 146,397 individuals who were treated for acute lower respiratory infection (ALRI) between 1999 and 2016 at Intermountain Healthcare facilities throughout Utah's Wasatch Front region. The levels of PM2.5 were estimated based on data from air quality monitoring stations along the Wasatch Front.

Study findings

• Short-term periods of rise in PM2.5 matched with the timing of increases in health care visits for ALRI.
• Infectious processes of respiratory disease may be influenced by particulate matter pollution at various levels.
• ALRI associated with elevated levels of PM2.5 was observed in both children and adults. The association was also present in newborns and toddlers up to age two.
• PM2.5 may damage the airway so that the disease causing virus can successfully cause an infection or PM2.5 may impair the immune response making the body is less effective in fighting off the infection.

While this study was conducted in a region where PM2.5 spike up occasionally, the team has not studied the effect on ALRI in regions where air pollution exposure is higher over the long term but short term spikes do not occur.

"In many places that have higher average PM2.5, the PM2.5 level does not vary as much as it does on the Wasatch Front, so it is not clear how this study's findings may transfer to those locales where the Air Pollution exposure is higher over the long term but short term spikes do not occur," said lead author Benjamin Horne, PhD, director of cardiovascular and genetic epidemiology at the Intermountain Medical Center Heart Institute in Salt Lake City, Utah. Dr. Horne. "It may be, though, that long-term exposure to air pollution makes people more susceptible to ALRI on a routine basis, although additional studies will be required to test this hypothesis."

The study findings suggest that when an acute increase in the level of PM2.5 occurs, people could prevent ALRI and alleviate symptoms by reducing their exposure to the air pollution.

References:

1. Air pollution - (http://www.who.int/ceh/risks/cehair/en/)

Source-Medindia