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Los Angeles: Nothing Like a Breath of Fresh Air


Ah, summer. Season of sizzling heat, fiery sunsets and jasmine scent wafting in the night air. Season of ozone buffeting gently in the breeze.

Flying home--from vacation, perhaps--you watch through the window as the sprawling Southland rolls into view, cloaked in a rusty, hazy shroud of nastiness--which you breathe, it occurs to you afresh, every day.

True, the smog has gotten much better down the years since its zenith in the 1950s, thanks to aggressive emissions control. But our air is still the worst in the nation. Hundreds of times a day, we drag it into our lungs. Hundreds of times our children drag it, too, into their own mini-lungs.

We're talking ozone. Carbon monoxide. Sundry oxides of nitrogen and a smorgasbord of carcinogens, the whole brew heavily peppered with teeny-tiny particles that originated anywhere from that fume-spewing bus in front of you to that burger Aunt Millie grilled you on her barbecue.

Are we out of our minds to even be inhaling? And what--short of packing up and bailing L.A.--can we do to lower our exposure and our risk?

The Situation Has Been Worse

First, by way of some perspective: We're not experiencing anything like the 1952 episode in London, when you couldn't see 10 yards in front of you and 5,000 people died in roughly a week from the dense smog caused by coal smoke. And there are plenty of other things we do, such as eat poorly and smoke heavily, that harm us more, experts say.

"I've heard people say that living in L.A. is like smoking a pack a day--clearly, that's nonsense," says Dr. John Peters, professor of preventive medicine at the USC School of Medicine. But risk--and risk we didn't sign up for--is still there. "Whether it's like smoking one cigarette a day, half a cigarette a day, a tenth a day--we don't know," Peters says.

On the one hand, there's strong evidence that smog can and does kill, that it can cause other ill effects such as inflamed lungs and loss of lung capacity, scientists say. The elderly, the infirm, children, people with breathing disorders like asthma, and those with heart disease seem particularly at risk. But it's unclear how many people are suffering, or what the long-term effects are of breathing in polluted air for decades.

"These are the questions," Peters says, "that everybody wishes they had answers to."

Scientists are beginning to provide some of those answers. Studies in various smoggy cities around the world are telling us more and more about the biological effects of smog. In Southern California, a large smog study is monitoring long-term health effects in thousands of children. And researchers are using new sophisticated smog-gathering equipment that collects and concentrates dirty air direct from our cities allowing them to study the health effects of polluted air more realistically than ever before.

Already, there have been surprises. Scientists used to think ozone was the most worrisome air pollutant for Angelenos.

Particle Pollution a Serious Hazard

"Today, scientists are increasingly finding that particle pollution is as much or more of a health problem than the ozone," says Bill Kelly, spokesman for the South Coast Air Quality Management District. This goes especially for the smallest particles, especially the ones spewed out in diesel exhaust.

Air pollution has always been kind of a feature of the Los Angeles basin: Hundreds of years ago, the region was known as the Valley of Smokes, because the fires of the Native Americans hugged the ground instead of rising and blowing away.

L.A.'s famous "inversion layer" is the cause: Warm air tumbling over the mountains traps colder air beneath it. The fumes from all those cars, trucks and factories stay in that lower, colder layer, around us.

What's in that heady mix? Ozone, which is great when it's up in the stratosphere but is definitely undesirable down here. Back in the 1950s, a Caltech chemist--who was studying the chemistry of pineapple flavor at the time--figured out how ozone was made: from sunlight, a motley mix of "volatile organic chemicals" (things like gasoline, paints, solvents and even chemicals from some trees) and chemicals called nitrogen oxides (from vehicle exhaust and power plants).

Scientists have done hundreds of studies on ozone's health effects: on people exercising in labs, kids running around at summer camps, on adults jogging, hiking or picking raspberries in polluted areas. The bottom line? Ozone, a very reactive chemical, inflames the walls of our bronchial tubes and lungs. Even in healthy people, lung function is temporarily reduced, especially when we're exerting ourselves. You can get chest pains or coughs. It takes hours for lung function to recover.

High ozone levels have also been linked to increased hospital visits, especially for people who already have lungs compromised from asthma, emphysema or bronchitis.

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