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Documenting the Dangers of Smog : Researchers are examining the long-term effects of air pollution, particularly on children. :


Jason Carrion, 15, and his friend, Bill, clad in baggy T-shirts and long shorts, stopped their bicycles and surveyed the gray smog devouring all but a faint silhouette of the nearby San Gabriel Mountains.

"It bothers us, when we're riding our bikes especially, because it gets hard to breathe," Jason said that recent afternoon in San Dimas.

The eyes sting. Deep breaths are painful. The throat is scratchy. These are well-documented discomforts brought on by exposure to the heavy smog that often shrouds the San Gabriel Valley, from Pasadena to Pomona.

But what about the long-term damage? There have been projections, but the precise effects remain a mystery, says an expert from USC.

"We've had pollution here for more than 40 years and nobody has done a study on chronic effects," said Dr. John M. Peters, director of occupational and environmental medicine at USC. "Is it the lifetime exposure (that causes damage)? Is it the last year's exposure? Is it the one-hour high ozone peak during the day? There's just so much we don't know."

Soon, however, they hope to have some answers.

For more than two years, Peters and a team of researchers have been immersed in an exhaustive study to answer numerous questions about local air pollution and pinpoint the damage that three categories of pollutants inflict on the lungs.

About 3,700 children from a dozen communities throughout California are taking part in the 10-year study, which includes extensive air monitoring and lung testing. In San Dimas, Jason Carrion and about 280 other youths are participating.

The hope is that the study will provide precise information so that policy-makers can set exacting air-pollution regulations and impose tougher controls, if need be, on lung-damaging emissions, Peters said.

Currently, pollution-control regulations and safety precautions are based on studies of short-term exposure and reactions. Experts project permanent lung damage based on those studies, he said.

"If you're starting to destroy lungs," Peters said, "you're willing to spend more money" to prevent the damage.

Some of the study communities were chosen because they have dirty air. Others were included because they have clean air. The rest are somewhere in the middle.

"San Dimas is one of the communities high in all three (types of pollutants)," Peters said.

That's no surprise.

When it comes to smog, the San Gabriel Valley is just about tops on every researcher's list. It is California's ozone laboratory and the nation's as well. In fact, area communities have been included in three other major air pollution studies in recent years.

Ozone is a colorless gas that, when high in the atmosphere, protects the Earth against the sun's harmful ultraviolet radiation. But at ground level ozone irritates the eyes and airways, resulting in sore throats, wheezing, coughs and shortness of breath.

Experts also fear that ozone tears at the lungs, damaging sensitive tissue and reducing a person's ability to absorb life-sustaining oxygen and the body's ability to ward off lung disease.

Historically, the most unhealthful ozone levels in the basin have been detected in the eastern San Gabriel Valley in Glendora, Azusa, San Dimas and neighboring communities, according to data from the South Coast Air Quality Management District. The AQMD regulates air pollution in Los Angeles and Orange counties and portions of Riverside and San Bernardino counties.

The AQMD's monitoring station in Glendora logged ozone levels in excess of state clean air standards on 148 days last year. Only one monitoring station--in Redlands in San Bernardino County--registered more days, with 160. The Glendora zone topped the list in 1992, when ozone levels exceeded state standards on 164 days.

Smog levels in the eastern San Gabriel Valley reached the more serious first-stage alert levels 19 times last year. The area is on the same pace this year with 10 first-stage alerts as Tuesday, according to the AQMD. That category of smog alert means it is unhealthful for anyone to exercise outdoors.

The AQMD's three other San Gabriel Valley monitoring stations also have documented plenty of lung-searing days, although not as many as at the Glendora station. Those stations are in Pasadena, Azusa and Diamond Bar.

Some of the smog is created locally by the valley's industry and traffic. But a large amount is imported, with weather and geography conspiring against clear skies.

Sea breezes blow pollutants from Los Angeles into the valley. The area takes a second hit from southwesterly winds that come off the ocean and blow Long Beach's industrial emissions through the Whittier Narrows and into the eastern San Gabriel Valley.

The trip from the coast takes just enough time for the sun to bake the pollutants into a witch's brew of ozone and other unhealthful compounds.

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