Air pollution from factories and vehicles is associated with worsening of the condition of people with lung diseases

According to a new study led by scientists at the University of Pittsburgh, people with unexplained lung scar disease are more
likely to die if they live in areas with high levels of air pollution made up of chemicals associated with industrial sources and vehicular traffic.

The study is the first to link
the chemical composition of fine particulate air pollution with worsening prognosis in fibrotic interstitial lung disease (fILD).
It is also the largest study
ever to assess the effects of air pollution on these patients.

"Some people with these lung diseases have a life expectancy of only a few years from diagnosis to death, but it's a mystery why they get the disease and why their lungs become so scarred," said
Gillian Goobie, MD, a doctoral candidate in the Department of Human Genetics at the Pitt School of Public Health.
"Our study points out that air pollution – particularly from factories and vehicles – may accelerate disease progression and premature death
in these patients.
"

Guby and her team obtained data from 6,683 patients with fILDs in the United States and Canada and linked their home addresses to air pollution data monitored by satellite and ground to determine the composition of air pollutants with an accuracy of less than half a mile
.

The team specialized in a pollutant called PM2.
5, which refers to particles smaller than 2.
5 microns in diameter, which is invisible to the naked eye
.
This type of contamination is so small that it can penetrate deep into the lungs and even into the bloodstream, where it can lead to other diseases beyond the lungs, such as heart disease
.

"In the past, most environmental health research has focused on a simple definition of PM2.
5," said co-author James Fabisiak, Ph.
D.
, an associate professor
in the Department of Environmental and Occupational Health at the Pitt School of Public Health.
"But the chemical composition of PM2.
5 is diverse, and its composition depends on whether it comes from forest fires or exhaust gases
.
Research lacks to determine whether the type of PM2.
5 affects health
.
Our new study is a big step in
filling this knowledge gap.
”

The team found that rising PM2.
5 levels were associated
with more severe disease at diagnosis, faster disease progression as measured by declining lung function, and a greater likelihood of early death.
Pollution with high levels of sulfate (often produced by factories, such as the coal and steel industries), nitrate (mainly from fossil fuel combustion), and ammonium (usually produced by industry or agriculture) was associated with worse outcomes, while chemical signatures from more naturally occurring particulate matter such as sea salt or soil dust were not as highly correlated
.

Guby noted that aerosols containing sulfates and nitrates form in the atmosphere after pollutants leave the chimney or exhaust pipe, and these aerosols and other gaseous pollutants can be acidic, which can cause very much damage
to tiny air sacs in the lungs.

The team is currently conducting laboratory studies to look at the effects of these pollutants on lung cells at the molecular level to better understand why they are particularly harmful to some people's lungs and whether exposure to pollutants triggers changes in the way certain genes work, leading to scarring out of control
.

According to the team's calculations, most premature deaths could have been avoided among participants living in areas with a high industrial burden in North America, including Pittsburgh
, if not exposed to industrial pollutants.
Participants of color were disproportionately exposed to higher levels of man-made air pollutants: 13 percent of the high-exposure group were non-white, but only 8 percent of the low-exposure group, highlighting the impact of environmental injustices in
these findings.

Co-senior author S.
Mehdi Nouraie, MD, PhD, associate professor of pulmonary, allergy and intensive care medicine at Pitt Medical School, said the findings further underscore the need for people whose lung diseases make them more susceptible to pollution need to pay attention to the Air Quality Index — a predictor of air pollution — and consider reducing time
outdoors or in rooms without good air filtration on days with poor air quality.

"Ultimately, we want to encourage data-driven awareness," Nouraie said
.
"We want people to think about the quality of the air
we breathe.
Patients, health care providers, and policymakers can all use the new information we provide in an effort to improve health outcomes
.
When you give the most vulnerable people safe air, you are keeping us all safe
.
”