AIR DIRTY IN 'CLEAN' SUBURB INVISIBLE SMOG INGREDIENT, OZONE, LURKS.

Byline: Nicholas Grudin Staff Writer

SANTA CLARITA - There are regions of California where you can stand surrounded by miles of wilderness and yet feel the burn of smog in your lungs. The countryside around Santa Clarita is such a place.

As the summer officially ends today and the air-pollution season winds down, Santa Clarita has once again tallied more smoggy days than almost any other city in the United States - 32 days through Friday when ozone levels were higher than considered healthy under federal standards.

The number of smoggy days was higher than in the Houston, Tex., region, widely known as one of the smoggiest urban areas in the nation.

``Air pollution doesn't pay attention to political boundaries,'' said Tim Carmichael, president of the Los Angeles-based Coalition for Clean Air. ``The fact is that air pollution generated in one community often impacts other communities and even communities hundreds of miles away.''

Just like some spots in San Bernardino and San Joaquin counties, the Santa Clarita Valley is - to residents' dismay - a dumping zone for the heavy emissions of a major urban center.

The semirural valley acts as a cul-de-sac for smog produced in the Los Angeles Basin and blown by sea breezes up the Sepulveda Pass and the Golden State Freeway.

The only regions in the nation with more smoggy days than Santa Clarita were Crestline and Redlands, both also choked with pollution from Los Angeles.

So far this year, residents of the Los Angeles Basin have suffered through more than double the number of high-ozone days as those in the nation's smoggiest region outside California. Through Friday, 61 days of high ozone levels somewhere in the Los Angeles Basin - an increase from 45 last year - compared with 26 days when ozone levels violated federal standards anywhere in the Houston area.

But of all of the places in the basin, from downtown Los Angeles to the San Fernando Valley, tarnished air most routinely finds its way into seemingly unlikely places - far from production of the emissions.

``What it comes down to is that there are three main (smog) transport routes out of the L.A. Basin - up the 5 Freeway, the 15 Freeway or the 10 Freeway. The receptor areas are Santa Clarita, the High Desert and the Coachella Valley,'' said Joe Casmassi, a senior meteorologist for the South Coast Air Quality Management District, the region's air-quality regulator.

According to Casmassi, combined wind patterns and chemical properties are to blame for the fact that a hike in the Placerita Nature Center will pump more dangerous ozone into your lungs than a jog down Temple Street.

Ozone is one of several criteria air pollutants considered highly toxic in large quantities. It has been linked to cancer and can be a cause of asthma in active children, according to a recent University of Southern California study.

Like many of the dangerous air pollutants, ozone is produced by industrial and vehicular emissions, reacting together in bright sunlight. But unlike some other pollutants - particulate matter, for example - ozone is invisible.

And, according to Casmassi, the properties of ozone make it more hazardous to outlying areas as its ingredients are transported by winds into spots where, over time, they ``cook'' together in sunlight.

``There is a delayed reaction, instead of reacting very close to the source,'' Casmassi said. ``The sea breeze blows the emissions. ... The maximum ozone readings occur when the smog cloud hits Santa Clarita.''

Officials for the city of Santa Clarita have recently expressed concern about the impact of Los Angeles smog on their city, but they say that little can be done on a local level.

And according to AQMD officials who visited Santa Clarita for a town hall meeting in August, their hands are also tied because they have jurisdiction over sources of only about 20 percent of emissions sources in the region - not over pollution from motor vehicles or on activity, such as oil production, on federal lands or in federal and state waters.

State and federal regulators say they are in the process of tightening restrictions on emissions and fuel.

But until air quality improves, Santa Clarita residents must adjust their habits, according to Jean Ospital, the AQMD health-effects expert.

``The risk comes from going outside and exercising when the smog levels are high. We advise that when the ozone levels are elevated, you try to avoid exercising when you can,'' Ospital said.

Therefore, on all 32 of the days when ozone levels in Santa Clarita violated federal health-based standards, children who were exercising outdoors were risking long-term lung damage.

``I could be permanently damaging my children's lungs by letting them exercise outdoors,'' said Teresa Savaikie, a local activist who has battled development in Santa Clarita. ``You want your kids to be physically healthy, but we're talking about permanent lung damage here.''

But despite the fact that much of the smog problem in Santa Clarita comes from Los Angeles, Carmichael believes that Santa Clarita is not as helpless as its officials claim in the fight against smog.

``Even for somebody who works on air pollution, Santa Clarita's problem is surprising. I guess the thing that ties it together for me is that there is a lot of construction and development going on there,'' Carmichael said.

``And it's very difficult to imagine a scenario where it gets better.''

The smog season does not officially end until Oct. 31, but AQMD officials do not expect too many more unhealthy days this year as the days get shorter and the ozone-cooking heat diminishes.

Nicholas Grudin, [phone]

nicholas.grudin(at)dailynews.com

CAPTION(S):

2 photos

Photo:

(1) Motor vehicles, major sources of pollution, travel through the Newhall Pass, as do invisible smog ingredients blown from utility plants and industry. Residents of Santa Clarita suffer.

(2) Santa Clarita officials say smog from vehicular traffic, utilities and industry travels to the city.

David R. Crane/Staff Photographer