Headlines
As reported by the Danbury News-Times, September 9, 2004.
Study Links Pollution to Weakened Lungs
By Robert Miller
Living in a city thick with air pollution is like living with second-hand cigarette smoke. It may take a while, but it eventually hurts a lot of people.
"It's not as bad as smoking, that's the worst," Dr. Gregory Dworkin, chief of pediatric pulmonology at Danbury Hospital, said Wednesday. "But it still affects the lungs."
A study published today in the New England Journal of Medicine offers compelling evidence the damage caused by air pollution is real and lasts a lifetime.
The Children's Health Study, led by the University of Southern California's Keck School of Medicine, studied 1,759 children in 12 southern California communities from the ages of 10 to 18, when human bodies, including lungs, do most of their growing.
The researchers kept track of the children's lung capacity, measured by the amount of air they could expel. They also carefully monitored air pollution in the 12 cities, zeroing in on select pollutants including nitrogen dioxide — one of the main chemical ingredients of ground level ozone, or smog — carbon, acid vapors and very fine particulate matter.
Over eight years, the researchers found a direct correlation: The children living in the most polluted cities had less lung capacity — in some cases, at least 20 percent less capacity than children living in the cleanest cities. Because girls have a smaller lung capacity than boys, they proportionately had a greater loss.
James Gauderman, associate professor of preventive medicine at USC's Keck School, said the researchers themselves were surprised at the extent of the damage heavy air pollution caused.
"We thought we'd see some relatively small effects that might be statistically significant," Gauderman said. Instead, the damage from air pollution was, at its worst, comparable to living with a smoker and breathing second-hand smoke.
Gauderman said the loss of lung capacity could translate into other diseases as people age, and shorten lives. And because the pollutants — created by motor vehicles and fossil-fuel burning industrial plants — are found throughout the cities of the United States, Gauderman said he and his researchers believe the health problems they found on the West Coast exist elsewhere.
"They'd be present in any urban setting," he said.
Doctors who got a chance to look at the study praised it for its completeness — the large number of children enrolled, the number of communities and the careful tracking of the pollutants.
"This study did a pretty nice job," said C. Arden Pope III of Brigham Young University of Provo, Utah, who wrote an editorial accompanying the study.
Dr. Eileen Storey, professor of occupational and environmental health at the University of Connecticut School of Medicine in Farmington, said doctors knew that breathing polluted air causes short-term problems, especially for people with pre-existing pulmonary diseases like asthma or bronchitis.
"What's new about this study is that it really describes a sustained loss of lung function and a diminishment of capacity," she said.
"The damage is real," Dworkin said. "The more pollution you're exposed to, the worse it is."
Pope said the study is also important because it showed the loss of lung capacity across the board.
"If children are breathing high levels of pollution, their lungs are not growing at the same rate," he said.
The most widespread form of air pollution in Connecticut is ozone — the combination of hot sunny days and nitrous oxides. But Gauderman said the study showed ozone, known to cause shortness of breath, doesn't cause long-term damage to the lungs.
Instead, researchers are increasingly concerned with particulate matter — the microscopic bits of ash emitted by motor vehicles and industrial sites. Connecticut's worst corridor for fine particulate matter is along Interstate 95 in southern Fairfield and New Haven counties.
Dworkin also said when rush-hour traffic slows to a crawl on Interstate 84 in Danbury, there are a lot of cars and trucks moving slowly along the highway over the city, emitting exhaust.
"This is the kind of issues we have in Danbury," Dworkin said. "That's the kind of pollution we're talking about."
Pope said these tiny particulates are not, in and of themselves, all that dangerous.
"The body would be better off it just ignored them," Pope said. "But it doesn't."
Instead, these tiny specks of pollution work their way down to the bronchioles in the lungs — the narrowest airways, measuring a 50th of an inch across. There, the body treats them as an irritant and the bronchioles become inflamed.
Dworkin of Danbury Hospital said years of breathing pollution causes chronic inflammation. Eventually, that inflammation becomes scar tissue, and people lose lung capacity.
This may contribute to lifelong lung problems, then heart disease. In June, the American Heart Association called air pollution "a serious public health problem," in part, because exposure to it can last a lifetime.
"People are breathing in a little of this pollution day after day, week and week, year after year," said Pope of BYU.
One important side effect of the study may be to alert people to the severity of the health problems caused by air pollution.
"We've all become a little complacent," said UConn's Storey. "We'd all like to believe the air is easier to breathe. I think we need to reevaluate that."
Much of Connecticut's air pollution comes from someplace else — the traffic-heavy highways in New York and New Jersey, and the giant fuel-burning power plants in the Midwest.
Storey said it's right for the state to try to cut pollution from outside sources.
"But mobile sources create a tremendous amount of pollution," she said of the state's cars, diesel trucks and buses. "You have to pay attention to both."
Dworkin said the study is also a reminder that the state and federal regulations that have successfully cleaned a lot of pollution from the air do matter — they make people's lives healthier, and save society money over the long-term.
"There's a reason why we have the Environmental Protection Agency, the Clean Air Act," he said. "There are things in life we can't change. But air pollution is one of the things we can change."
Information from the Associated Press was used in this report.