PERSONAL HEALTH : Air Sickness : Evidence Mounts of Serious Damage and Early Aging of Children’s Lungs

Under the terms of the ambitious air quality plan in store for Southern California, pollution is supposed to vanish by the time today’s newborns enter college.

The painful question is whether clear skies will come too late for children already familiar with smog alerts.

While it’s recognized that children, because of their physiology, are at greater risk than adults from breathing noxious air, the outlook for their long-term health risks has been as hazy as a smoggy day.

But evidence is mounting that young people reared in heavily polluted areas unknowingly bear a common signature in prematurely aged lungs and a reduced tolerance for respiratory problems.

* According to short-term studies, children living in regions with poor air quality have decreased lung capacity compared with youths raised in cleaner cities. Studies also show children suffer more respiratory infections and asthma attacks from exposure to air pollution.

* And, in one of the first studies examining the lifetime impact of growing up under brown skies, researchers have found lung tissue damage in seemingly healthy Los Angeles youths, an ominous finding that experts say demands further attention.

The youths “were running out of lung,” said Dr. Russell P. Sherwin, a USC pathologist who performed autopsies on 100 youths, all victims of accidents or homicides. The lung damage was far greater than what pathologists would expect to find, even among youngsters who smoke cigarettes, said Sherwin. He reported his study last month at the Specialty Conference on Tropospheric Ozone and the Environment held in the City of Industry. “Some of them definitely must be smokers. But the damage I’m seeing is above and beyond what we’ve seen with smoking. It’s above and beyond what we’ve seen with (respiratory) viruses.”

The common denominator for the youths, Sherwin said, was air pollution.

According to experts, such emerging research highlights the need for reappraising how to minimize children’s risk of lung damage, short of fleeing the South Coast Air Basin. The research might even spur stricter air quality laws, so long talked about but so difficult to enact.

“In many ways, children are very good monitors in knowing that there is a danger in the environment for all of us,” said Dr. Richard Jackson, a Berkeley-based researcher on environment and children’s health. “There is something causing direct damage in the lungs, the people most likely to show it are kids.”

“The more we know about children, the cleaner we’re going to make our environment,” said Bob Phalen, a professor of community and environmental medicine at the UC Irvine. “There is a soft spot for children. And it’s necessary that we have a soft spot for children because children tend to not complain. They don’t speak up and they don’t get checked out.”

Most children begin life with a healthy set of lungs. But youngsters also have physical traits that allow lung damage to accumulate faster than in any other group.

Children consume more oxygen than adults to maintain body warmth, Phalen said. An infant, for instance, breathes three times as much air per pound of body weight as an adult.

“Right there, whatever is in the air, they’re getting three times more pollutant per pound of body weight,” he said.

Children are also more likely to breathe faster and through their mouths, especially while playing. Breathing through the nose filters out as much as 90% of some pollutants before they reach the lung.

And children, especially those under 10, are more sensitive to damage because their lungs are still developing.

The result is that children are receiving concentrated doses of pollutants that they are less equipped to handle, Phalen said. Computer models show that children can receive three to four times as many pollution deposits as adults, he said.

Actual studies on children have also linked air pollution to short-term health problems.

Children breathing high levels of air pollution, for example, have more respiratory tract infections, such as colds and croup, than those who breathe clean air, experts said. Asthma is also known to worsen from exposure to pollution. According to the National Center for Health Statistics, asthma among 6- to 11-year-olds jumped 58% in the 1970s.

“Some of the ingredients of air pollution diminish the lungs’ ability to fight off infection,” Phalen said. “I think the scientific community is very convinced that air pollution is increasing the susceptibility to respiratory infection. Respiratory infection is already a problem, and anything that increases that susceptibility should be looked at very seriously.”

Lung function tests suggest that children might be suffering from exposure to pollutants long before the damage is obvious. Lung function is measured by determining the intake of air and how fast it’s exhaled.

According to a USC study, second-grade children raised in the South Coast Air Basin suffered a 10% to 15% loss in lung function compared with Houston children. The study was performed in 1984 and again three years later.

“We looked at some of these children again in 1987 and we saw the same degree of reduction,” said Dr. Kaye Kilburn, the USC professor of medicine who directed the study. “They fulfilled the prediction: They did not improve their function as fifth-graders.”

A 10% to 15% decrease wouldn’t produce any outward signs of trouble but might subtly erode athletic performance, said Kilburn. The difference between Houston and Los Angeles children remained consistent even among children exposed to their parents’ cigarette smoke, he said.

But many of studies do not take into account other factors that might affect lung function, such as smoking, exposure to secondhand smoke, poor hygiene, poor nutrition, polluted indoor air and exposure to chemicals and other toxic substances, Sherwin said.

Moreover, the studies fail to answer major questions about the future of children growing up in one of the worst regions of air pollution in the world:

* What is actually happening to cells in the lung?

* Is the damage permanent?

* What illnesses or diseases could emerge from this damage?

“A great deal is known about the respiratory system of children,” Phalen said. “A great deal is known about their susceptibility to respiratory tract disease. There is knowledge about what happens to children in severe episodes of pollution.

“What is not known is whether the day-to-day levels of the smog that we have in Southern California are putting children at greater risk than adults. There is strong circumstantial evidence for that, however.”

Sherwin’s study of autopsies is the first to show precursors of lung disease among youths living in a polluted environment.

The study revealed that 80% of the youths had “notable” lung abnormalities and 27% had severe lesions. The lesions were found in a region of the lung known to be vulnerable to noxious substances.

A crucial phase of the study has not been completed, however. It will determine what other factors might have contributed to the lung damage, such as whether the youths, ages 15 to 25, smoked.

“No single agent can be implicated as the sole cause of this lesion,” Sherwin said. “But the bottom line for me is even if I consider that the most of these people are smokers, I’m seeing much more damage than I would expect to see. It’s much more severe, much more prevalent. And these are pretty young people.”

The study is one of the few attempting to address the possible consequences of a lifetime of exposure to air pollution, said John R. Holmes, director of research at the California Air Resources Board, which sponsored the study.

“One of the ways to do that is to look at the lungs of younger people who have been exposed to smog but haven’t yet begun to show any physical manifestation of damage,” he said. “The lung has immense reserve capacity. You can sustain large amounts of damage but you don’t realize damage has occurred.”

According to Sherwin, the youths with lung lesions were at high risk of developing emphysema or other lung diseases, even though they apparently had no symptoms of disease.

If the youths had lived, Sherwin said, “I would say they would have a very high probability of clinical disease within 15 to 20 years--by the time they get to be 40.”

Experts agree that studies such as Sherwin’s must be expanded to measure the cumulative effects of air pollution on children growing up in different parts of the country.

“We don’t know whether (damage) is permanent or not. We think it probably is,” Kilburn said of his study on lung function. “The ideal evidence would be to play musical chairs and move people in and out of the area. But it’s hard to fund a study like that.”

The research on children should also address the adequacy of guidelines designed to minimize children’s risks, Phalen said.

According to South Coast Air Quality Management District officials, vigorous exercise should be replaced by such activities as golf, horseback riding, swings, or shooting baskets during Stage 1 alerts and by walking and crafts during Stage 2 alerts. Last year, Southern Californians experienced 54 Stage 1 days and no Stage 2 days.

But, according to Phalen, those guidelines should be tailored to individuals. He said he recently consulted with physicians and environmental experts after he was asked to issue guidelines to school nurses for smog-alert days.

“One of the things we recommend--really it was a consensus--was that on smog-alert days children should be allowed outdoors because indoor pollutants are often worse,” he said. “But under no circumstances should they be forced to exercise. Children are often in circumstances where they are forced to exercise. That alarms me because our natural defenses include shutting down our activity.”

When exposed to heavily polluted air, many people unconsciously secrete extra mucus, breathe through the nose, slow down and breathe less air, Phalen said. The bronchial tubes constrict and become narrower.

“These effects warn susceptible people,” he said.

But individual reactions vary and children who wish to play and exercise should be allowed to do so, Phalen said.

“One of the facts about air pollution--that every study has found--is that the individual differences are quite large. Some people don’t seem to be affected,” he said.

Parents can also contribute to their children’s protection by becoming more aware of the hazards of indoor air pollution, said Dr. Spencer Koerner, an American Lung Assn. volunteer spokesman and director of pulmonary medicine at Cedars-Sinai Medical Center in Los Angeles.

“Clearly, the one thing parents should do is stop smoking,” Koerner said. “Even here in California, we’re inside much of the time. I think that kind of exposure is important.”

And, Phalen said, well-meaning parents often obtain antibiotics for their children’s respiratory infections, but antibiotics might only prolong youngsters’ problems in regions with poor air quality.

“The child can get into a cycle of infections, and we tend to treat them with antibiotics,” he said. “But what happens is microorganisms repopulate as soon as you stop taking the antibiotics. So you get sick again. That’s called the rebound effect.

“One of the best things parents can do is try to minimize antibiotics use in their children. Parents should tell their pediatrician: ‘If you don’t think my child needs it, I don’t want my child to have antibiotics.’ ”

How Pollution Damages Lungs Autopsies of seemingly healthy youths who died in accidents or were murdered revealed lung damage in the form of lesions in the bronchioles. Such lesions have been associated with several noxious substances, including those found in polluted air.

The bronchioles are small tubes that lead to tiny air sacs in the lung. They link the major bronchial tubes with those sacs, which are called alveoli.