By Gene Emery
BOSTON (Reuters) - In the first long-term study of air pollution's effects on children, researchers reported on Wednesday that contaminated air stunts lung development in teenagers and the effects could extend well into adulthood.
The findings, published in the New England Journal of Medicine, show that existing pollution controls in many parts of the United States are inadequate.
The researchers, who followed 1,759 children in a dozen southern California communities, said pollution is probably having a similar effect on children elsewhere.
The youngsters were tested for eight years beginning at age 10, just before their lungs began their final maturation spurt.
James Gauderman of the University of Southern California and his colleagues found that 7.9 percent of the 18-year-olds in the highest pollution areas had lung capacities that were less than 80 percent of what they should have been.
Among teenagers subjected to the least-polluted air, only 1.6 percent had underperforming lungs.
The damage was seen in teens who had never smoked and had never had asthma.
"This is some of the most convincing evidence that air pollution has chronic effects," Gauderman told Reuters. "We see the effects in all kids. And it's an unavoidable exposure. It's not like smoking, where you can advise people to stop. This is a day-in-day-out kind of exposure."
The damage, he said, may be permanent.
"By the time they reach their late teens, their lung development has pretty much stopped," said Gauderman.
At that age, lower lung capacity may translate into wheezing during a cold or a bout with the flu, or make it harder to recover after an illness, he said.
But because adults lose about 1 percent of their lung capacity each year, beginning in their late 20s, teens with lame lungs face greater risks if serious illness subsequently strikes.
"In your 50s and beyond, low lung function is a major risk factor for death from respiratory illness or heart disease," he said.
Although southern California is notorious for its bad air, Gauderman said pollution levels had declined in the last two decades so the amount of dirty air there is comparable to most urban centers.
In an editorial in the Journal, C. Arden Pope of Brigham Young University in Provo, Utah, said the findings showed that "the control of air pollution represents an important opportunity to prevent disease."