"People may not realize what they are dealing with," said Rob Paine.
A pulmonologist at University Hospital, member of the Air Quality Board and head of the U.'s new Program for Air Quality, Health and Society, he said Utahns might overlook the health impacts of summer smog because it doesn't look threatening like that brown, hazy winter smog.
"It's clear but it has a huge effect," he said. "People may not realize what they are dealing with."
What is ozone pollution? Unlike the upper-atmosphere ozone layer that protects life on earth by screening out the sun's harmful rays, ground-level ozone damages health.
The pollutant is created when three oxygen atoms form ozone, or O3, which is one of those oxidants that people try to counteract when eating blueberries, pomegranates and other foods high in antioxidants. The recipe for smog isn't complete until those ozone molecules, which are unstable, combine with emissions from tailpipes and smokestacks and "cook" in the sun.
It's an oxidant gas, said Elena Craft, a health scientist with the Environmental Defense Fund. It burrows into the tiniest crevices of the lungs, the alveoli, where clusters of microscopic air sacs help feed oxygen into the bloodstream and whisk away carbon dioxide as a waste product.
And it affects everyone, said Craft.
Babies to seniors • Scientific studies have measured ozone impacts even in the womb, with mothers exposed to high levels delivering low-birthweight babies. Also suffering are newborns, whose lungs develop most rapidly just after birth.
New studies link smog not just to triggering asthma attacks, but also to causing the condition. And, for older people with cardiovascular trouble, exposure to smog is also a risk.
"It does shorten life," added Janice Nolen of the American Lung Association, noting that ozone is the most widespread air pollutant and increasingly shown to be much more harmful than previously understood. "It can cause early death."
Nolan mentioned a recent study of Galveston, Texas, lifeguards that showed a decline in lung function even in healthy people who breathed smog.
"The more we learn, the more complicated it gets," she said. "So it shouldn't be taken lightly."
The lung association's most recent State of the Air report gave Salt Lake County an "F" grade for high ozone. But the group also singled out rural Uintah County for ozone pollution, an odd winter problem there that has been linked to oil and gas industry emissions.
"People don't always know how important air pollution is to their health," said Nolan.
Ozone nation • The same report said nearly 4 in 10 people in the United States more than 119 million people live in areas with unhealthy levels of ozone.
Her organization is joining the American Medical Association, the American Lung Association, American Academy of Pediatrics, the American Thoracic Society and others in urging the EPA to tighten allowable smog limits.
"The medical and health care community has been vocal in support of the science for a more protective ozone standard," said Craft, whose group also backs the tougher limits.
Meanwhile, the rural ozone connection is one that is getting more attention in Utah.
Recent studies by the Utah Division of Air Quality have shown ozone levels at or over the health-based standard set by the U. S. Environmental Protection Agency in Parleys Canyon, Erda in Tooele County and even Antelope Island, where buffalo are more likely to cause traffic jams than motorized vehicles.
"Often in these pristine places," said Utah pulmonologist Paine, "we still have exposure."
Last month Department of Environmental Quality Director Amanda Smith told a congressional subcommittee the high background levels of smog might be drifting into the rural West from Asia, falling from the upper atmosphere or other as-yet-unknown sources. Regardless, it's creating concern that much of the West may fail to achieve a tightened air-quality standard because of those background levels.
While it's unclear how the issues will shake out in the regulatory world, the obvious solution for individuals is to take control of their personal health by watching daily forecasts, tracking hourly readings, monitoring personal symptoms and avoiding conditions that might lead to avoidable harm.
"It requires that you remain vigilant about the quality of the air you are breathing," said Craft, "and that's definitely a day-to-day responsibility."
Self defense: Ozone and you
The Utah Asthma Program and the advocacy group, Breathe Utah, offer some tips:
• Avoid outdoor exercise on smoggy days, roughly noon to 6 p.m.
• Sign up for pollution alerts from the Utah Division of Air Quality at http://www.airquality.utah.gov/
• Check DAQ's daily forecasts, current conditions and trends, especially on hot, sunny days when the air is stagnant
• Download the Android and Apple apps at EPA's AirNow http://m.epa.gov/apps/airnow.html
• Take action to limit pollution, such as driving less, using low-fume paints, personal care products and small engine.
• Take heed of symptoms, including unexplained fatigue, chest tightness and a even small cough. Some people experience health effects even before health alerts are issued.