Lung Damaging Air Strikes Orange County Amid Soaring Heat, Smoke

ORANGE COUNTY, CA — Lung-damaging ozone pollution in Orange County and Los Angeles has reached its highest levels in a generation and set records in other parts of Southern California during the blistering Labor Day weekend heatwave, according to air quality readings.

Southern California has long suffered the nation's worst levels of ozone. The corrosive gas inflames the lungs and triggers asthma attacks and other health problems. Pollution from cars, trucks, factories, and other sources bakes in the heat and sunlight contributes to ozone formation.

According to a report from the Los Angeles Times, it no coincidence that the highest ozone readings usually happen when the weather is hottest.

Ozone pollution spiked to 185 parts per billion in downtown Los Angeles at midday Sunday, according to data gathered by the Diamond Bar-based South Coast Air Quality Management District. This was the highest hourly reading in Southern California since 2003 and the highest in downtown L.A. in 26 years, the Los Angeles Times reported Friday.

In Orange County, Sunday's eight-hour average ozone reading in Mission Viejo was 123 ppb, the highest on record since monitoring began at that location in 2000, according to The Times. Mission Viejo reached temperatures of 113 degrees that day, according to the Weather channel.

Sunday's readings at the downtown L.A. air monitoring station, located on North Main Street in Chinatown, were so far above average that they triggered a quality control check designed to prevent the release of erroneous data, air quality officials told The Times.

The eight-hour average ozone level in downtown L.A. was 118 ppb, "very unhealthy" on the Air Quality Index, and far above the federal standard of 70 ppb. The last time ozone readings were that high in downtown L.A., by either measure, was in 1994, at a time when emissions were much higher and smog dramatically worse, The Times reported.

The downtown L.A. readings did not initially appear online and were provided by the South Coast air district in response to questions from The Times about the missing data.

The figures lagged due to quality control checks. Additional, manual validation is standard protocol when pollution readings exceed historic highs, South Coast AQMD spokeswoman Nahal Mogharabi told the newspaper. If instruments are having problems, they "can show erroneously high levels, and the quality control check prevents the automated release of high data that could be incorrect."

But it was no glitch.

"The value for noon on Sunday has been reviewed and is preliminarily valid at 185 ppb," Mogharabi said.

Air quality officials said the high pollution readings resulted from intense heat combined with stagnant weather conditions and winds that were too weak to sweep away much pollution.

Temperatures in Los Angeles County exceeded 120 degrees Sunday for the first time on record, thanks to a high- pressure system that also trapped dirty air close to the ground and allowed smog levels to build up.

Climate change is an underlying cause of the increase in smog, according to air quality experts cited by The Times. Scientific studies have found that rising temperatures make smog harder to control by speeding up the photochemical reactions that generate ozone gas. And wildfires, which are growing more intense and destructivewith the warming climate, only spew more smog-forming pollutants into the air.

With worsening air quality lingering across the Southland, a Cedars-Sinai lung specialist warned the public to stay indoors as much as possible to limit exposure to ash and smoke from area wildfires that are causing gloomy skies throughout California.

RELATED: 12 Dead; 3.1M Acres Burned; 3,900 Structures Lost: C.A. Fires Map

Dr. Zab Mosenifar, medical director of the Women's Guild Lung Institute at the Los Angeles hospital, said he has detected a "noticeable increase in the last few days" of patients complaining of coughing, shortness of breath, and chest tightness.

Even if you live 25 to 40 miles away from a wildfire, your lungs can be affected by small particulates.

"It's very unhealthy," he said.

When the air is poor, stay indoors if you can, close your windows, and run the air conditioning. Masks — particularly N95 masks — are also helpful, according to authorities.

The smoke-filled skies are attributed to statewide fires Fire, which started in a lightning storm on Aug. 17

In Los Angeles County, the Bobcat Fire in Angeles National Forest that started Sunday exploded to nearly 24,000 acres with 0 percent containment.

See more:

• Glowing Orange Sun Over The Pacific: Photo Of The Day
• Venice Beach Sunset At The Waves: Photo Of The Day

City News Service, Patch Editors Nicole Charky, Ashley Ludwig contributed to this report.