Los Angeles is still the nation’s smoggiest city


Metropolitan Los Angeles, extending to Riverside and Long Beach, remains the smoggiest city in the United States, with an average of more than 140 days a year of dangerous ozone levels, the American Lung Assn. reported Wednesday in its annual assessment.

All of the nation’s 10 smoggiest counties are in California, with San Bernardino, Riverside, Kern, Tulare and Los Angeles leading the pack. And the state’s cities and counties, with their ports, refineries, power plants and crowded freeways, rank near the top for particle pollution.

“This is not just a nuisance or a bother,” said Bonnie Holmes-Gen, the lung association’s California policy director. “Thousands of people are being rushed to emergency rooms. Thousands of people are dying early as a result of air pollution.... It is a crisis.”

The report comes at a time of conflict over the state’s efforts to slash emissions. Citing the recession-battered economy, trucking and construction firms are seeking to delay California’s rules to limit diesel pollution from operating big-rigs, forklifts and other equipment.

A proposed ballot initiative, sponsored by oil companies and conservative activists, would suspend the state’s climate law, which targets carbon dioxide and other greenhouse gases but could effectively curb traditional air pollutants such as ozone and particles.

Jane Warner, president and chief executive of the California branch of the lung association, urged state officials to maintain proposed curbs on diesel emissions and to step up efforts to promote electric cars. “We also call on Californians to reject the Texas oil companies’ attempt to undo California’s clean air and clean energy laws,” Warner said.

The ballot initiative to delay AB 32, the Global Warming Solutions Act, is spearheaded by San Antonio-based Valero Energy Corp. and Tesoro Corp., which operate major refineries and hundreds of gas stations in California.

Despite its grim overall statistics, the report took note of remarkable progress in some areas: The number of high-ozone days has dropped by 25% in metropolitan Los Angeles and by 57% in metropolitan San Francisco, which includes Oakland and San Jose, since 2000.

Ground-level ozone, or smog, forms when nitrogen oxide gases and volatile organic compounds, such as gasoline vapors, react in the sunlight and heat. Inhaling ozone, which is colorless and odorless, can cause asthma and shorten lives.

Particle pollution, also known as fine particulate matter, combines soot, dust and aerosols and often contains mercury and other toxic substances. It causes respiratory disease, heart attacks and premature deaths.

The report found that high air pollution levels threaten the health of 175 million people, about 58% of the population. But in California, the proportion is far higher: 91% of state residents, more than 33 million people, live in counties with poor air quality, especially in Southern California and the Central Valley.

Annually, California’s dirty air is estimated to cause 19,000 premature deaths, 9,400 hospitalizations and 300,000 respiratory illnesses.

The U.S. Environmental Protection Agency is weighing tighter limits on ozone and particles, and Congress is considering Clean Air Act amendments to further cut emissions from coal-fired power plants. Other issues under consideration: whether federal construction projects should use only clean-diesel equipment and whether the federal government should finance retrofits of operating diesel trucks, as California has.

Only two cities appear on all three of the lung association’s lists of cleanest cities — for ozone, for year-round particles and for short-term measures of particles: metropolitan Fargo, N.D.; North Dakota, which also includes Wahpeton, Minn.; and Lincoln, Nebraska.

The report is interactive: readers can go to the website,, type in their ZIP Codes and find out how their neighborhoods rank.