Merced County's air got another F rating but it's a better F this time.
The American Lung Association's annual state of the air report shows Merced has the ninth-worst ozone levels out of 277 metropolitan areas in America.
The association looks at ozone levels and particulate levels. Studies have shown ozone can make asthma and chronic lung conditions worse, and particulates increase the risk of lung cancer, heart attack and stroke. Every county in the Central Valley got an F, along with Mariposa County. The counties that received an A included Humboldt, Lake, Marin, Mendocino, San Francisco, San Mateo, Santa Cruz, Siskiyou and Sonoma
"It's a wake-up call to remind us we have very serious pollution that is harming public health," Bonnie Holmes-Gen said. She's the senior director for policy and air quality for the American Lung Association in California.
Some of that pollution is inevitable, according to Henry Forman, a professor of chemistry and biochemistry at UC Merced and an appointed scientist on the San Joaquin Valley Air Pollution Control District board.
"We sit in a bowl where there's a lot of sunlight, a lot of dust and a lot of traffic going through," Forman said. "And if we didn't have any people living here at all, there would still be a fair amount of ozone because of the geology of the area."
Despite the F rating, there was some good news in the report.
"We have seen a lot of progress in the northern part of the San Joaquin Valley," Holmes-Gen said. "The clean air laws are working."
Although there has been some progress, the Valley has a long way to go before the air can be called clean.
"California is set to adopt a new set of vehicle standards in the fall," Holmes-Gen said. "We can do a lot more to clean up our cars and get more alternative fuel vehicles on the road."
Holmes-Gen said curtailing a lot of wood-burning has made a difference in the Valley's air. "Wood smoke is a big source of pollution in the winter, and the rules are working."
Forman said he believes the air district is doing a good job of trying to decrease the particulates and ozone in the air. But he's also critical of some of the new standards the Environmental Protection Agency is issuing.
"We couldn't meet some of those standards even if there were no people here," Forman said. "We have a natural amount of ozone here. There are a lot of places in the environment where things are toxic, and it's not necessarily something people did. Here we have ozone."
For more information on the lung association's state of the air report, go online to www.stateoftheair.org.
Reporter Carol Reiter can be reached at (209) 385-2486 or email@example.com.