A bad year for ozone pollution has earned Las Vegas an F from the American Lung Association.
Valley smog levels now rank as the 16th worst in the nation, according to the association’s annual “State of the Air” report released Wednesday.
But the community is holding the line on dramatic improvements it has made for dust and other forms of air pollution in recent years, the report said.
“The air in Las Vegas is certainly cleaner than when we started the ‘State of the Air’ report 14 years ago,” Amy Beaulieu, director of programs at the American Lung Association in Nevada, said in a statement.
“Even though Las Vegas experienced increases in unhealthy days of high ozone, the air quality is still better compared to a decade ago.”
Despite the low marks for ozone, the community continues to meet U.S. Environmental Protection Agency health standards for the pollutant, though just barely, said Dennis Ransel, planning manager for the Clark County Department of Air Quality.
“What we really worry about is how the EPA characterizes us. That’s the real boss,” he said.
But while he quibbles with some of the criteria the American Lung Association uses to arrive at its rankings, Ransel supports the overall message.
“It creates publicity and awareness that dirty air isn’t good for people,” he said of the association’s annual report. “The point is pollution is a serious problem.”
Ransel said there were 19 days last year when unhealthy levels of ozone were detected by at least one of the valley’s 11 monitoring sites.
In 2010, that happened on a single day.
“It was a high year for sure. We’re not entirely sure of the reason,” he said. “The problem is it’s hard to pinpoint the source.”
That is because ground-level ozone, the key ingredient in smog, is not a direct emission.
It forms in the air — and typically builds up during daytime hours — through the combination of heat, sunlight and pollutants such as gas fumes, car exhaust and smoke.
Ozone season is now under way in the valley.
Ground-level ozone, a key ingredient of urban smog, can become a pollutant of concern here as early as April and continue through the hot summer months.
Residents can do nothing about wildfire smoke and other ozone-causing pollution that blows in from another state.
But they can cut down on local emissions by driving less and not filling up their cars or running their lawn mowers in the middle of the day, Ransel said.
Unhealthy amounts of ground-level ozone can worsen respiratory illnesses such as asthma and bronchitis, but it also can induce coughing, wheezing and shortness of breath even in healthy people.
“It irritates the lungs is what it does,” Ransel said.
When ozone levels are elevated, officials advise everyone to limit strenuous outdoor activity.
Despite improvements nationwide, the American Lung Association’s report found that more than 131.8 million people, more than four in 10 Americans, still live in counties with unhealthy levels of either ozone or particle pollution.
California cities dominated the list of places with the dirtiest air. The six worst for ozone and the seven worst for year-round particulate pollution were all in the Golden State.
Back in the Las Vegas Valley, Ransel said he was glad to see the Lung Association acknowledge the strides that have been made in reducing some airborne pollutants, particularly dust.
“That’s been a real success story,” he said. “We used to run F’s there.”
Contact reporter Henry Brean at email@example.com or 702-383-0350.