Editor's Note: Trend charts and rankings for metropolitan areas and county grades are available at Lung.org/sota
The American Lung Association's 2018 "State of the Air" report found Nashville ranked as the 62nd -most polluted city in the nation for ozone. This is in keeping with a trend seen across the nation of higher ozone pollution levels.
"The 2018 'State of the Air' report finds that unhealthful levels of ozone in Nashville put our citizens at risk for premature death and other serious health effects such as asthma attacks and greater difficulty breathing for those living with a lung disease like COPD. Such high levels of ozone pollution mean our citizens also face an increased risk for lung cancer" said Heather Wehrheim, Director of Advocacy for the American Lung Association in Tennessee. "Across the nation, the report found continued improvement in air quality, but still, more than four in 10 Americans - 133.9 million - live in counties that have unhealthful levels of either ozone or particle pollution, where their health is at risk."
The trends reported in this year's report, which covers data collected by states, cities, counties, tribes and federal agencies in 2014-2016, reflect the ongoing challenges to reduce each pollutant in the changing political and outdoor climate.
"We can and should do more to save lives," Wehrheim said. "The Lung Association in Tennessee calls on our members of Congress to defend the Clean Air Act, currently under threat from those who want to weaken this effective public health law. We also call on the U.S. Environmental Protection Agency to implement and enforce the law instead of trying to roll back major safeguards like the Clean Power Plan and cleaner cars, both steps that help us fight climate change and reduce air pollution."
Each year the "State of the Air" provides a report card on the two most widespread outdoor air pollutants, ozone pollution, also known as smog, and particle pollution, also called soot. The report analyzes particle pollution in two ways: through average annual particle pollution levels and short-term spikes in particle pollution. Both ozone and particle pollution are dangerous to public health and can increase the risk of premature death and other serious health effects such as lung cancer, asthma attacks, cardiovascular damage, and developmental and reproductive harm.
Ozone Pollution in Nashville
Compared to the 2017 report, Nashville experienced more unhealthy days of high ozone in this year's report. In fact, Nashville ranked 62nd in the nation for most polluted for ozone compared to 93rd last year.
"Ozone especially harms children, older adults and those with asthma and other lung diseases," said Heather Wehrheim, Director of Advocacy of the American Lung Association in Tennessee. "When older adults or children with asthma breathe ozone-polluted air, too often they end up in the doctor's office, the hospital or the emergency room. Ozone can even shorten life itself."
This report documents how warmer temperatures brought by climate change make ozone more likely to form and harder to clean up. This year's report showed that ozone levels increased in most cities nationwide, in large part due to warmer temperatures in 2016, the second hottest year on record in the U.S. Over the past decades, ozone pollution has decreased nationwide because the nation has cleaned up major sources of the emissions that create ozone, especially coal-fired power plants and vehicles.
Particle Pollution in Nashville
The 2018 report also found year-round particle pollution levels significantly improved although this was the first year to have data since 2014. Nationwide, the best progress in this year's report came in reducing year-round levels of particle pollution.
"Particle pollution is made of soot or tiny particles that come from coal-fired power plants, diesel emissions, wildfires and wood-burning devices. These particles are so small that they can lodge deep in the lungs and trigger asthma attacks, heart attacks and strokes, and can even be lethal," said Wehrheim. "Year-round particle pollution levels have dropped thanks to the cleanup of coal-fired power plants and the retirement of old, dirty diesel engines."
"State of the Air" 2018 also tracked short-term spikes in particle pollution, as these can be extremely dangerous and even lethal. The report found that Nashville has slightly more days when short-term particle pollution has reached unhealthy levels in 2014-2016. Davidson County still ranked at a weighted average of a B grade with 0.3 days of spikes.
Many of these spikes in Nashville were directly linked to weather patterns like drought or to events like wildfires, which are likely to increase because of climate change and high emissions from wood-burning devices.
While the report examined data from 2014-2016, this 19th annual report provides online information on air pollution trends back to the first report covering 1996-1998.
Learn more about Nashville rankings, as well as air quality across Tennessee and the nation, in the 2018 "State of the Air" report at Lung.org/sota.