By JENNIFER SINCO
HONOLULU — The Big Island received a failing grade for particle pollution in the air, according to an American Lung Association report card released Wednesday.
But that’s because one of the island’s main sources of particle pollution is volcanic smog, commonly known as “vog.”
“The trade winds generally blow the vog off-shore in a way that still makes the Big Island a beautiful place,” said Steve Businger, a University of Hawaii meteorology professor and vog expert. “Unfortunately, it’s not something we can control.”
The association’s “State of the Air 2013” report card gave Hawaii County an “F” despite a decrease in the number of days with unhealthy particle pollution — from 23.5 days in 2012 to 12.5 this year. Particle pollution is a mix of very tiny solid and liquid particles in the air. If they’re small enough, they can stay in the air for long periods, Businger said.
Honolulu is the only county in the state that collected data on ozone levels. There were no days of unhealthy levels of ozone, or smog, which is the most widespread air pollutant.
Maui County received healthy grades for particle pollution. According to the report, figures available for Kauai County were incomplete.
Volcanic gas emissions from the Big Island’s Kilauea volcano create vog. If the trade winds stop or if wind blows in the opposite direction, other islands including Oahu, Maui and Kauai, experience the condition. Kilauea has been in constant eruption since Jan. 3, 1983.
Still, people should be assured that Hawaii’s overall air quality is clean, Businger said.
“I don’t think people need to worry unless they happen to be very sensitive to vog,” Businger said. He added that on days when vog levels are high, people should stay indoors, limit outdoor exercise and drink plenty of fluids.
The annual report grades counties nationwide for ozone and particle pollution levels. Cheyenne, Wyo., ranked No. 1 in the top 25 cleanest cities for year-round particle pollution. Bakersfield-Delano in California ranked the worst for particle pollution, while California’s Los Angeles-Long Beach-Riverside region had the worst ozone ranking.