Long-Term Lung Damage Linked to Air Pollution : Health: Respiratory deterioration is found in areas where air is dirtiest. The effects appear to be permanent.

UCLA researchers say an 11-year study has demonstrated for the first time that the deterioration of lung function is long lasting with chronic exposure to air pollution, whether it be Southern California smog or East Coast-style industrial smokestack emissions.

A host of earlier experiments had revealed lung irritation lasting a day or two in people who breathe polluted air for several hours. But the long-term study of three middle-class Los Angeles County neighborhoods showed that “pollution is more than an inconvenience,” said principal investigator Roger Detels, an epidemiologist.

“There may be irreversible changes in people who are chronically exposed,” he said. Poor lung function can leave people vulnerable to respiratory disease, such as emphysema, and can affect stamina. Some of those studied suffered as much as 75% loss of lung capacity.

Detels was particularly disturbed, he said, by the damage discovered in children. Lung capacity generally increases until age 20 and then begins to decrease slowly, but researchers found a slower rate of growth among children in the polluted areas.

“People who have grown up in these highly polluted areas may expect to have even greater difficulties with respiratory problems as they reach old age,” he said.

The seven-member UCLA team tested and surveyed residents in Glendora, where the wind piles smog against the foothills; in a Long Beach community downwind of several oil refineries and bordered on two sides by highways, and in Lancaster, where the desert air is relatively clean. Overall, about 2,500 people participated.

Results of the Long Beach portion of the survey were published in the March issue of the American Journal of Public Health. The Glendora results were published previously.

The testing was staggered between 1972 and 1983, with each participant being examined two times, five to six years apart. The results took years to analyze because of problems with funding, Detels said.

“It is a landmark study,” said John Holmes, research director of the California Air Resources Board. “We have needed to know about the effects not just of the bad ozone day, but of the bad ozone year and the bad ozone decade.”

Holmes said the research confirms suspicions raised by USC autopsies in which lung damage was discovered in the bodies of young people from Los Angeles.

“But we were not sure in those cases what the exposures were,” Holmes said. “This study shows exactly what levels of pollution were involved.”

None of the subjects in the UCLA study had ever smoked, Detels said. Monitoring stations for the South Coast Air Quality Management District tracked the pollutants in each area.

The Glendora group was consistently exposed to some of the highest levels of ozone in the nation. The Long Beach residents, near the coast where ozone is lower, were breathing high levels of sulfur and nitrogen oxides, along with sulfates and hydrocarbons--a mix, Detels said, common to polluted East Coast and Midwest cities.

The Lancaster community was subject to moderate doses of ozone--about half the level of Glendora--and to very low levels of other pollutants. Ozone, a key component of smog, irritates eyes and produces tightness in the chest, headaches and dry throats.

A mobile laboratory traveled to each of the three neighborhoods, testing and retesting participants who ranged in age from 7 to 59.

The first measurements found average lung capacity was markedly lower in the polluted neighborhoods of Glendora and Long Beach than in Lancaster. The second set of measurements found that the average rate of deterioration was also greater where the air was dirtier. Researchers said there was no indication the lungs would heal over time.

They could not distinguish differences in the nature of impairment due to varying pollutants. In Glendora and Long Beach alike, Detels said, both large and small airways were found to be narrowed by pollution.

The narrowing kept air from being evenly distributed throughout the lungs, resulting in an inefficient delivery of oxygen to body organs, Detels said.

Few of those tested complained of wheezing, coughs, shortness of breath or chest colds. “We would tell them and we would tell their physicians that their lung capacity was 50% to 75% less than what it should have been, and they would be very annoyed,” Detels said.

“They would say they were fine. But I suspect that these people had modified their lifestyles thinking they were experiencing the natural aging process. They weren’t.”