The American Lung Association gave San Diego a failing grade Wednesday it its latest ranking of pollution levels across the country.
The San Diego metropolitan area was ranked 6th worst nationally for ozone pollution, with a 42 percent increase in the number of unhealthy days since the 2015.
“San Diego has achieved notable reductions in unhealthy air days over the 19 years of our State of the Air reports; however, this year’s report shows an uptick in unhealthy days for ozone,” the lung association said.
While Los Angeles led the nation in ozone pollution, San Diego ranked worse than New York, which came in at 10th.
The lung association said San Diego is backsliding because rising temperatures from global warming are increasing the frequency and severity of ozone days.
“Federal and state policies like the Clean Air Act and strong California clean car standards are working. We are reducing pollution emissions, but the impacts of climate change are interfering with progress,” said Bonnie Holmes-Gen, a senior director for the lung association in California.
Ozone pollution is caused by chemical reactions resulting from emissions by motor vehicles and industry in the presence of sunlight. Breathing ozone can trigger a variety of health problems, particularly for children and the elderly.
California accounted for eight of the 10 U.S. metropolitan areas with the worst ozone pollution.
“The reality is California still has unhealthy levels of air pollution in large areas of the state, which puts Californians at risk for premature death and other serious health effects such as asthma, COPD and lung cancer,” said Holmes-Gen. “We must continue the life-saving work of cutting air pollution and slowing climate change.”
There’s a bit of good news for San Diego in the case of another type of pollution. The metro region saw its best rankings for short-term and year-round particle, or soot, pollution with just over one unhealthy air day.
Since 2000 San Diego has seen a 61 percent reduction in unhealthy ozone days, and since 2004 a 94 percent drop in unhealthy particle days.