The 50 U.S. Cities With the Worst Air Quality

More than half of all Americans -- 166 million people -- live in places where they are exposed to unhealthy levels of year-round particle and ozone pollution, according to the American Lung Association. Every year the association produces the State of the Air report, which details pollution levels at official monitoring sites. The best and worst cities in the United States are ranked under three categories: short-term particle pollution, year-round particle pollution and ozone pollution. Acute effects caused by high ozone levels are generally reversible, whereas “long-term exposure to air polluted by particulate matter” can exacerbate chronic disorders like heart disease and diabetes. If you’re curious about the air you’re breathing, here’s the ALA’s list of the 50 U.S. cities with the worst year-round pollution.

50. Charleston, West Virginia

Charleston is the capital city of West Virginia, making it a metropolis of business and culture. Throughout the year, Charleston hosts FestivALL Fall, a citywide celebration of visual art, music, dance, theater and more. It includes more than 130 events and 360 performances. Unfortunately, the Charleston-Huntington-Ashland metropolitan area also hosts a high concentration of dangerous air pollutants, due to its proximity to gas fields and industrial plants, according to West Virginia Public Broadcasting. Deborah Brown, president and CEO of the American Lung Association of the Mid-Atlantic, tells the Charleston Gazette-Mail that the area needs “stronger air-quality standards” in order to continue improving its air.

44. Rome, Georgia

The 15 Most Deadly Countries for Air Pollution

Learn More

Rome, Georgia, sits on seven foothills of the Appalachian Mountains surrounding three rivers that meet in the downtown area. The Oak Hill/Martha Berry Museum illuminates the story of Appalachia, while the Chieftains Museum provides a glimpse into Cherokee history. The city also is also home to Berry College, which ranks 7th among colleges in its region, according to the U.S. News and World Report. Coastal Georgia benefits from air currents from the Atlantic that help to clear the air. Unfortunately, Rome is about as far from the coast as you can get in Georgia. Growing population and traffic congestion contribute to the poor air quality there, according to the Rome News-Tribune.

44. Raleigh, North Carolina

Raleigh is North Carolina’s capital city. It’s nicknamed the “City of Oaks” for the oak trees that beautify the city. Locals call Raleigh-Durham-Capital Hill the Research Triangle because those three cities house North Carolina State University, Duke University and the University of North Carolina, respectively. The triangle made the ALA’s list for having some of the highest levels of year-round particle pollution in the United States. Tom Mather, spokesperson for the North Carolina Department of Air Quality, tells ABC-11 that since the Clean Smokestack Act passed in 2002, power plants have cut their emissions by about 75 percent. ALA director Melissa Forde says that the area still has a long way to go.

44. Milwaukee, Wisconsin

What Are Top 10 Worst States for Allergies?

Learn More

With more than 17 museums and 150 state and county parks, Milwaukee is Wisconsin’s largest city. For 11 days every year, it hosts Summerfest, the world’s largest music festival. If that’s not enough, visitors and locals can enjoy a variety of cultural celebrations throughout the year, including Mexican Fiesta, Polish Fest, Bastille Days, Indian Summer Festival, German Fest and Irish Fest. Milwaukee borders 22,300 miles of Lake Michigan. Research found that 31,961 square miles of the Great Lakes are contaminated with mercury from industrial plant emissions, according to Environment Michigan. Those emissions end up not only in the water, but also in the air the locals and visitors have to breathe.

44. Columbus, Ohio

Columbus, Ohio’s capital and largest city, bustles with activity and culture. It ranked 32nd on Bloomberg’s list of America’s 50 Best Cities. It’s home to Ohio State University, which is among the top universities in the nation. While Columbus finds itself in the top 50 U.S. cities with the worst year-round particle pollution, Shelly Kiser, advocacy director for the ALA in Ohio, says that the federal Clean Air Act standards are working. “We’ve cleaned up our federal coal-fired power plants. We’ve moved toward gas-fired power plants. We’ve moved toward more renewable energy. We’ve cleaned up our diesel. Those things are all working,” she tells The Columbus Dispatch. According to them, Ohio legislators are currently working against policies that would help to clean the air, such as those requiring more of the state’s energy to come from renewable sources and President Barack Obama’s Clean Power Plan.

44. Chattanooga, Tennessee

Several bodies of water surround Chattanooga, including Chickamauga Lake and Nickajack Lake, which are part of the Tennessee River. Expansive bridges radiate out across rivers from its central downtown area. The city is home to the Chattanooga Choo Choo, a museum of railroad history and model trains. The city’s fleet of zero-emission electric buses provides transportation for commuters and visitors, but it could stand to expand this fleet to further improve air quality.

Related: Learn more about visiting Chattanooga, Tennessee.

44. Atlanta, Georgia

The birthplace of Martin Luther King Jr., Atlanta is a busy metropolis packed with lofty skyscrapers. Its dome-topped Georgia State Capitol building was constructed in 1889, and its metropolitan area is the eighth-largest economy in America and 17th-largest in the world. It’s also home to the global headquarters for The Coca-Cola Company, UPS, Home Depot, AT&T and Newell-Rubbermaid. It’s no wonder that pollution is a problem in such a populated area. Michael Halicki of the Clean Air Campaign advises Atlanta residents to “run errands consecutively instead of separately … and skip the drive-through.”

43. Baltimore, Maryland

Baltimore is located in central Maryland along the Patapsco River and the Chesapeake Bay. It is home to a large seaport, and the downtown area is centered on the gorgeous Inner Harbor. However, the Washington-Baltimore-Arlington area creates difficult geographic challenges “from air pollution from power plants, animal waste and fertilizer and pollutions washed off hard surfaces by runoff,” according to a CBS Baltimore report. The metropolitan area should begin by strengthening laws for power plant emissions.

Related: Learn more about visiting Atlanta, Georgia.

41. Youngstown, Ohio

Youngstown is situated on the Mahoning River southeast of Cleveland. Originally a steel-manufacturing locus, today Youngstown is the only city in the United States with a population that has decreased more than 2 percent in recent years. Youngstown can reduce pollution by strengthening emissions controls, and Ohio is already well on its way: The U.S. Environmental Defense Fund Report recently named Ohio as a leader in reducing air emissions and creating jobs.

Related: Learn more about visiting Youngstown, Ohio.

39. South Bend, Indiana

South Bend is home to the prestigious University of Notre Dame. The campus is famous for the awe-inspiring Basilica of the Sacred Heart, which features beautiful high ceilings and stained-glass windows. Visitors can also peruse the Grotto of Our Lady of Lourdes, a small replica of a French shrine, where students light candles and pray. Despite improvements in other counties throughout Indiana, South Bend experienced an increase in short-term particle pollution. It also ranked higher on the year-round particle pollution list than ever before this year, according to an ALA press release.

39. Missoula, Montana

According to University of Montana chemistry professor Tony Ward and Missoulian, 55 to 80 percent of outdoor air pollution in Missoula comes from wood smoke sources. These sources include smoke from woodstoves, prescribed burning and forest fires, which are exacerbated by climate change causing hotter and drier summers. “Particles that size are not just causing coughs or bronchitis or lung cancer,” former director of women’s health at St. Patrick Hospital Dr. Georgia Milan tells Missoulian. “They’re getting absorbed into the bloodstream and causing heart attacks, strokes and immune system dysfunction.” Factors that are helping to improve the Missoula air quality include improvements in automobile engine exhaust, traffic reduction and the growing usage of woodstoves that burn cleaner, according to Missoula City-County air-quality specialist Ben Schmidt.

39. Hattiesburg, Mississippi

In the late 19th century, Captain William Harris Hardy planned railroads from Meridian to New Orleans and from the Gulf Coast to Jackson. At their intersection he established Hattiesburg, named for his wife. Present-day Hattiesburg’s population is more than 148,000. The city’s African American Military History Museum is the only public World War II-era United Service Organization club in the U.S. that’s built for African-American soldiers. Animal lovers can stop by the Hattiesburg Zoo, which has added more than 20 new facilities since 2010.

36. Terre Haute, Indiana

One of the smaller communities on the ALA’s list, Terre Haute was a quarter-finalist in this year’s America’s Best Communities prize competition, which provides grants toward community revitalization. The Coca-Cola bottle was created there in 1915, and it’s home to the world’s first pay toilet. According to television station WTHR, the largest sources of air pollution in Indiana are power plants. “Here in Indiana, we are under assault by thousands of megawatts of coal-fired electricity, and coal-fired power plants are the biggest polluters on the planet,” ValleyWatch founder John Blair tells WTHR. Coal-fired power plants release arsenic, lead and mercury along with millions of pounds of carbon dioxide, nitrogen oxide and sulfur dioxide into the air. Locals can help by using less electricity to burn less coal and driving less to reduce gasoline use.

36. San Diego, California

San Diego’s hilly downtown area descends to its oceanfront boardwalk in a charming display of “city meets nature.” The city stretches north to the quaint surfing town of Encinitas and south to the border of Mexico. According to Fox 5 News, climate change is largely to blame. The prolonged drought and frequent heat waves in the San Diego-Carlsbad area have made it difficult to clean the air. The American Lung Association’s Debra Kelley advises San Diegans to “create more communities where walking and biking are encouraged. More public transportation would help too.”

Related: Learn more about visiting San Diego, California.

36. New York, New York

New York, the city that never sleeps, is home to some of the most iconic landmarks of the United States. The Statue of Liberty, Ellis Island, Central Park, the Empire State Building, the Guggenheim Museum and the Metropolitan Museum of Art are all notable landmarks of the Big Apple. The city is making great strides to reduce pollution by setting forth a number of municipal codes. Still, air quality in the New York-Newark area can be further improved through large-scale environmental development plans like the recent Staten Island Bluebelt, an ecologically sound storm-water management program.

Related: Learn more about visiting New York, New York.

33. Owensboro, Kentucky

According to its website, Owensboro is the “industrial, medical, retail and cultural hub of western Kentucky.” It borders the Ohio River, making Smothers Park a beautiful outdoor destination for visitors. Unfortunately, the Ohio River leads the nation in industrial pollution, according to the Courier-Journal. While Owensboro has poor air quality when it comes to year-round particle pollution, it actually made the ALA’s “cleanest” list in the short-term particle pollution category. “If we can do more to save lives, we should and we can,” Heather Wehrheim, director of advocacy for the ALA, says in a press release. “The Lung Association calls on Kentucky’s leaders to develop a strong strategy for implementing the Clean Power Plan and reinstating our state’s renewable energy and energy efficiency standards to reduce harmful emissions from power plants that worsen climate change and immediately harm health.”

33. Dallas, Texas

Dallas was historically a center for the oil and cotton industries. The arterial Trinity River is surrounded by the lush Greenbelt Park bordering downtown, providing stunning views of the city skyline reflected in the river. Sadly, the Dallas-Fort Worth area has had “little traction in improving air quality,” according to the Texas Tribune. The city can further reduce pollution by strengthening regulations on coal plant emissions.

Related: Learn more about visiting Dallas, Texas.

33. Columbus, Georgia

Columbus developed along the Chattahoochee River, which spans 434 miles down to the Georgia-Florida border. Visitors and residents enjoy the RiverWalk, a 15-mile path that ambles along the river. For anyone looking for daring adventure, the Chattahoochee River also lodges the longest urban whitewater rafting in the world. While the Columbus-Auburn-Opelika metropolitan area ranked poorly in the year-round particle pollution category, it received an “A” grade from the ALA when it came to ozone pollution levels.

31. Medford, Oregon

For anyone who loves pears and trains, Medford is the place to be. It’s the birthplace of Harry & David, the gift-basket company that specializes in the luxurious Comice pear. Visitors can also stop by the Medford Railroad Park, built on a 49-acre former sewage-treatment plant. It features miniature built-to-scale steam trains (that you can ride for free), full-size cars and locomotives and a working telegraph system. Wildfires are a major air pollutant in the Medford-Grants Pass area of Oregon. Climate Central found that air quality in cities within 50 to 100 miles of a wildfire experience air quality five to 15 times worse than normal. According to them, the Douglas Complex and Big Windy fires made the air quality in Grants Pass unhealthy for people to be outside for nine days in the summer of 2013.

31. Kansas City, Missouri

Known as the City of Fountains, visitors can see more than 200 water features that dapple the city. The J.C. Nichols Memorial Fountain was built in Paris in 1910 and salvaged from a scrapyard. It features four horsemen representing the four rivers of the world. And, purchased in 1920 in Venice, Italy, the Meyer Circle Sea Horse Fountain features three mythological sea horses. Unfortunately, Kansas City experiences high levels of sulfur dioxide. James Turner of the Sierra Club tells KCTV 5 that coal-burning factories are to blame for the high levels of air pollution in Kansas City. This year a chemical spill at a distilling plant in nearby Atchison released a noxious cloud into the air that sent 34 people to the hospital, according to KRQE News 13. Wind conditions helped to disperse the cloud.

28. Shreveport, Louisiana

The Red River divides Shreveport from Bossier City, which together earned a 28th spot on the ALA’s list of the worst U.S. cities for year-round particle pollution. Marylee Orr, director of Louisiana Environmental Action Network, tells the Shreveport Times that there are a number of factors that contribute daily to air pollution there. These include “Calumet Specialty Products emissions, the hydraulic fracturing process that follows oil and gas well drilling throughout the Haynesville Shale area, lignite mining and burning at the AEP-SWEPCO/CLECO plant near Mansfield, paper and pulp mills like International Paper Co. and even routine open burning of hardwoods and pine forests for vegetation control.” Orr urges the community to “be aware and participate” in air quality control.

28. Macon, Georgia

Just southeast of Atlanta, Macon houses North America’s only reconstructed earth lodge, a type of Native American dwelling. William Butler Johnston, ignobly known as the keeper of the Confederate treasury, left behind the Hay House, an 18,000-square-foot Italian Renaissance Revival mansion, which is open to visitors. Like much of the nation, the Macon-Warner Robins metropolitan area saw its air quality improve this year. The city can thank improvements in transportation and power plant emissions, June Deen of the American Lung Association of the Southeast tells Georgia Health News. The implementation of “green” locomotives, which WABE (Atlanta’s National Public Radio station) reports would use one diesel engine to run two trains, could further progress toward cleaner air.

28. Evansville, Indiana

According to Jamie Smith Hopkins from the Center for Public Integrity, there are seven coal-fired power plants within 30 miles of Evansville. “A third of the toxic air releases in 2014 from power plants, factories and other facilities came from just 100 complexes out of more than 20,000 reporting to the U.S. Environmental Protection Agency,” she writes in USA Today. Academics call these plants “super polluters.” Mary B. Collins, a State University of New York College of Environmental Science and Forestry researcher, found that low-income communities and people of color are disproportionately exposed to poor air quality created by super polluters. And although Indiana is one of the biggest coal-burning states, it has no renewable-energy requirements and no contingency plan regarding climate change.

26. Phoenix, Arizona

As with many of the cities on this list, Phoenix’s geography is detrimental to the city’s air quality. The central valley forms a concave region that traps pollutants. Although the city is surrounded by the natural beauty of the mountains and desert landscapes with blooming saguaro, poor air quality discourages enjoyment of that splendor. At dusk, the Cholla Trail on Camelback Mountain features sweeping views of the glittering valley to one side and the Scottsdale foothills on another -- if you can see past the pollution. The city currently displays large signs above freeways reading, “HIGH POLLUTION ADVISORY. CARPOOL -- USE BUS,” but more proactive steps are necessary for air-quality improvement. The Phoenix-Mesa-Scottsdale area of Arizona can improve air quality by further developing public transportation to support its growing population.

Related: Learn more about visiting Phoenix, Arizona.

26. El Paso, Texas

El Paso has a rich cultural heritage, mapping a past of political turmoil and transition. Visitors can learn about Native American culture at the Tigua Indian Cultural Center of the Ysleta de Sur Pueblo, which “celebrates over 300 years of tribal history in El Paso,” according to the Visit El Paso website. According to Environmental Health News, more than 80 percent of residents identify as Hispanic, and the city’s poverty rate is 6 percent higher than the state average. Trucks traveling along the U.S.-Mexico border, railways, the El Paso International airport and Fort Bliss, the second largest military base in the country, all contribute to air pollution in the El Paso-Las Cruces metropolitan area. According to ABC-7, the city’s air-quality manager, whose name is omitted from the article, says that officials have no current plans to reduce emissions.

25. Little Rock, Arkansas

Little Rock is a Midwestern town situated on the banks of the Arkansas River and serves as the capital of Arkansas. And there’s no shortage of trees or natural beauty: The edge of the city is nestled in foothills of the Ouachita Mountains. Its state capitol building is a replica of the White House and was built with Arkansas granite and features Tiffany chandeliers and a dome with a 24-karat gold-plated cupola. But investing in advertising to encourage commuter rideshares would reduce emissions and improve air quality.

Related: Learn more about visiting Little Rock, Arkansas.

23. Wheeling, West Virginia

Wheeling’s Grand Vue Park is a beautiful destination for anyone who loves the outdoors. If that’s not enough, there’s the Centre Market, the Eckhart House, the Good Zoo, Grave Creek Mound and more. Annual year-round particle levels have been improving since 2010, according to the Charleston Gazette-Mail. Fred Durham, director of the Division of Air Quality for the state Department of Environmental Protection, tells the Gazette “the reductions in ground-level ozone and particulate matter across the country can be attributed to efforts to reduce emissions, particularly nitrogen oxide.” Kevin Steward, American Lung Associations director of environmental health for the mid-Atlantic region, suggests that air-quality standards need to be stricter to combat pollution.

23. Fairbanks, Alaska

Pollution from wood burning -- in stoves and backyard furnaces -- is a major problem in Fairbanks. “Most people think of Alaska as one of the last great escapes from urban pollution,” Kim Murphy writes for the Los Angeles Times. “But they have not spent a winter in Fairbanks or the nearby town of North Pole, where air-quality readings in November [2013] were twice as bad as Beijing’s.” Wood and coal burning is a hard habit to break for the city’s residents, who live in one of the world’s coldest inhabited regions, especially since they have limited access to natural gas. The area’s first-ever burn ban was issued in November of 2015. Environmental groups are currently suing the EPA for their failure to change the Fairbanks North Star Borough designation from moderate to serious. The change would force the region to enact stricter measures, “such as requiring power plants to place additional filters in their smokestacks,” the Associated Press reports. “Old wood and coal stoves would also need to be removed before a home can be sold.”

22. Birmingham, Alabama

Birmingham was founded in 1871 as a center for railroad transportation and mining. Little has changed: Coal mining and manufacturing remain central to the city’s economy. Birmingham’s picturesque skyline rises to views of the Appalachian Mountains in the distance. Birmingham boasts more green space per capita than any other American city and is home to the 19-acre Railroad Park, with lakefront biking trails, sculptured gardens and fountains. This wealth of natural beauty should be protected, and the city’s active Metropolitan Planning Organization is taking good measures to clear the air in the Birmingham-Hoover-Talladega area of Alabama by planning to improve public transportation, maintain strict emissions standards and promote rideshares.

Related: Learn more about visiting Birmingham, Alabama.

21. Erie, Pennsylvania

Erie is located (you may have guessed) on the coast of Lake Erie, where industrial plants are major contributors to air pollution. The production of coke, a fuel made from coal, has been an issue in Erie for some time. The Environmental Protection Agency is currently suing Erie Coke because it claims that “the company has failed to fix leaks of the chemical benzene, excessive exposure to which can cause cancer,” explains. Kevin Stewart, director of environmental health for the ALA, tells the Allegheny Front that the implementation of the Cross State Air Pollution rule -- an EPA standard aimed at improving air quality -- will help to clean the air. “Once that happens, that will help us meet the air-quality standard and spread the burden of meeting that air-quality standard out more equitably according to the sources where that pollution originates,” he says.

20. Detroit, Michigan

In River Rouge, a town just outside Detroit, there are 52 sites of heavy industry within a three-mile radius, according to Newsweek. The area has also been “out of compliance” with federal restrictions on sulfur dioxide for years. State officials finalized a plan this year that requires four industrial operations in the Detroit area to reduce their sulfur dioxide emissions. “We keep spending more and more money on these plants that just are marginally performing units,” James Clift, policy director of the Michigan Environmental Council, tells the Detroit News. “If you look at the pollution and the public health impacts and calculated that against the cost of replacing those plants, it would be a simple answer that we should not continue operating them.”

16. Johnstown, Pennsylvania

Johnstown, Pennsylvania (aka “Flood City”), has been a canal port, railroad center, steelmaking center and coal mine. Visitors can check out the Johnstown Inclined Plane, the steepest vehicular incline in the world, which connects downtown to the higher grounds of Westmont Borough. On a quieter day, visit the Johnstown Flood National Memorial, which honors the 2,209 citizens who died when the South Fork Dam failed in 1889. The city winds along the Conemaugh River, which could explain why it has some of the worst year-round particle pollution in the country. Carnegie Mellon University professor Albert Presto charted air pollution in Allegheny County, just 70 miles west of Johnstown, and found that the river valleys had the most heavily concentrated air pollution. “The emissions can get trapped down there,” he tells WESA, Pittsburgh’s NPR news station.

16. Lancaster, Pennsylvania

The heart of “Dutch Country,” Lancaster is located in central Pennsylvania and is the oldest Amish settlement in America. An Amish community still thrives here, relying on horse-drawn carriages for transportation and eschewing electricity. Perhaps non-Amish residents can learn from the low carbon footprints of their neighbors: “Lancaster’s air still stinks,” reports Lancaster Online. Deb Brown, CEO of the American Lung Association of the Mid-Atlantic, recommends that to improve Lancaster’s air quality, “We must set stronger health standards for pollutants and clean up sources of pollution in the York region to protect the health of our citizens.”

Related: Learn more about visiting Lancaster, Pennsylvania.

16. Houston, Texas

Houston is the fourth largest city in the United States after New York, Los Angeles and Chicago. The city is known for the Sam Houston monument erected in honor of General Sam Houston, the president of the Republic of Texas. With such a booming population, the city’s Green Houston initiative recommends carpooling, walking, biking and using mass transit to reduce carbon emissions.

Related: Learn more about visiting Houston, Texas.

16. San Luis Obispo, California

Called America’s Happiest Town on “The Oprah Winfrey Show,” San Luis Obispo is lauded for its beautiful location and laid-back culture. “The Central California Coast is wine country unspoiled, where vineyards still border cattle ranches, big-city tastes mix with simple pleasures, and you can’t tell the billionaires from the beachcombers,” Conde Nast Traveler reports. Although California’s statewide emissions of smog-forming pollutants have decreased by more than 50 percent since 1990, the ongoing drought threatens to undo the state’s progress, according to the 2015 report California’s Progress Toward Clean Air that was released by the California Air Pollution Control Officers Association. The association calls for tougher federal standards.

14. Altoona, Pennsylvania

Altoona developed around the railroad industry. As such, many of its main attractions honor its history with the Pennsylvania Railroad, including the world-famous Horseshoe Curve. Drive along this feat of engineering at the base of the Allegheny Mountains, accomplished by the toil of about 450 workers. Visitors can also see the aptly named Altoona Curve baseball team play at the Peoples Natural Gas Field. Unfortunately, the city came in 14th place on the ALA’s list of cities with the worst year-round particle pollution and 39th on its list for short-term particle pollution.

14. Cincinnati, Ohio

The Great American Ball Park, home of the Cincinnati Reds, is a major attraction for locals and visitors alike. Tourists can also stop by the Cincinnati Zoo, where tickets start at $16 for adults and $12 for children. Unfortunately, outdoor activities may not always be an option for the 213,812 locals with asthma. Major factors include traffic emissions and topography. “Similar to California’s Central Valley, high traffic volumes in the Cincinnati area contribute to high pollution levels,” 247 Wall St. writes. “In addition, the city is located in a valley, which, like the mountains surrounding the Central Valley, helps trap emissions.”

13. Indianapolis, Indiana

Indiana’s capital city is known for sporting events, such as the annual Indianapolis 500, the NHRA U.S. Nationals, the Big Ten Conference football championship and the NCAA basketball tournament. Forbes ranked the city as one of the nation’s best downtown areas, lauding the Fountain Square district for its “growing and productive bohemian vibe that is a big part of the city’s identity.” It’s no surprise that pollution is a problem in Indianapolis because it’s a locus for manufacturing and industry as well as a distribution center for companies like Target, FedEx Express, Amazon and CVS. The key to reducing particle pollution in the Indianapolis-Carmel-Muncie area of Indiana involves passing laws regulating power plant pollution.

Related: Learn more about visiting Indianapolis, Indiana.

12. Philadelphia, Pennsylvania

Historically, Philadelphia played a major role in the American Revolution: The Founding Fathers met in Philadelphia to sign the Declaration of Independence in 1776 and the Constitution in 1787. The city is rich in history as well as greenery. The gorgeous Fairmount Park is the largest landscaped urban park in the world. Unfortunately, the air quality in the Philadelphia, Reading and Camden area of Pennsylvania, New Jersey, Delaware and Maryland ranks among the worst in the nation. To improve air quality, Joyce Epps of the Pennsylvania Department of Environmental Protection Bureau of Air Quality recommends “the retirement, deactivation or shutdown of certain coal-fired power plants.”

Related: Learn more about visiting Philadelphia, Pennsylvania.

11. Cleveland, Ohio

Cleveland’s picturesque downtown is situated on the banks of Lake Erie in northern Ohio. The city is known for the Rock and Roll Hall of Fame and a robust economy owing to such diverse industries as manufacturing, financial services, biomedical and health care. All of this has left the air in the Cleveland, Akron and Canton area of Ohio polluted. The Ohio EPA says, “We want to keep our environment clean, but we enjoy modern conveniences that create pollution, like air emissions from electric plants and automobiles and hazardous waste like leftover paint and cleaning chemicals.” Many coal plants in the area support the economy, and the state is currently considering how to reduce coal plant emissions while maintaining profitability.

Related: Learn more about visiting Cleveland, Ohio.

10. Louisville, Kentucky

Louisville, one of the oldest American cities west of the Appalachian Mountains and situated adjacent to the Falls of the Ohio River rapids, is home to the Kentucky Derby and headquarters of Kentucky Fried Chicken. The city has more than 120 parks and the nation’s largest urban forest. About a third of the country’s bourbon is manufactured in Louisville. While the liquor-derived economic boon is certain, manufacturing taxes the ecology of the Louisville, Jefferson, Elizabethtown and Madison area of Kentucky and Indiana. How can Louisville improve air quality? According to Louisville’s Courier-Journal, “Louisville needs a strong regulatory agency to lead the way. Whether [they] have one, however, remains uncertain. The Louisville Metro Air Pollution Control District was rocked last year by state and federal audits that found its air-monitoring data could not be trusted.”

Related: Learn more about visiting Louisville, Kentucky.

9. Harrisburg, Pennsylvania

As Pennsylvania’s capital, Harrisburg is a manufacturing powerhouse. The steel, coal and food industries are booming in the city, along with the nearby Hershey’s chocolate manufacturing center. Harrisburg is sadly known for the Three Mile Island accident, a partial nuclear meltdown in 1979 that was the worst disaster in American nuclear history. The toxic problems continue, as the city is often covered in brown-tinged smog. Local news site PennLive says of the issues: “Much of the area’s problem is attributed to its high concentration of trucking businesses and the presence of Interstate 81 and the Pennsylvania Turnpike and the traffic they bring. There’s also a coal-fired power plant near York Haven in York County. Local experts have also said the region is greatly impacted by power plants in other areas.” It seems that regulating the manufacturing industry is key to improving air quality in the Harrisburg, York and Lebanon area of Pennsylvania.

Related: Learn more about visiting Harrisburg, Pennsylvania.

8. Pittsburgh, Pennsylvania

With miles of riverfront trails, Pittsburgh residents and visitors enjoy running and walking along the city’s Allegheny and Monongahela Rivers. These converge near central downtown at Point State Park, a gorgeous spot to take in the reflections of the high-rise buildings’ lights on the water at sunset. The Pittsburgh, Newcastle and Weirton area of Pennsylvania, Ohio and West Virginia can thank emissions for their high rank on this list. According to WESA, Pittsburgh’s NPR news station, pollution rolls into Pennsylvania “from nearly 300 coal-fired power plants in 15 states and the District of Columbia.” However, the air quality is the best it’s been in the past 17 years, ever since the report has been published. National Senior Vice President of Advocacy Paul Billings tells WESA that this is due to the continued improvement of “transit use, regulation of pollution-causing industries and public awareness.”

Related: Learn more about visiting Pittsburgh, Pennsylvania.

7. San Francisco, California

San Francisco is the cultural and financial hub of Northern California. It’s famous for sites like Alcatraz, the Golden Gate Bridge, Coit Tower, Fisherman’s Wharf and the Painted Ladies. It’s also known for its bohemian, provocative counterculture in which beatniks and hippies flourished. Unfortunately, extensive mountain ranges surround San Francisco, trapping air pollution. Despite its high rank on ALA’s list of worst cities for year-round particle pollution, San Francisco has been striving toward cleaner air for more than 40 years, according to China Dialogue. Recently, it has raised California motor vehicle-emissions standards, adopted specifications for lower pollutant-emitting fuels and implemented “measures to improve traffic flow” and “promote carpooling and more transit use,” the publication writes.

6. Modesto, California

Despite Modesto’s motto claiming it as the city of “water, wealth, contentment and health,” the city’s San Joaquin Valley location creates environmental challenges because pollutants stagnate between its surrounding mountains. While there’s no shortage of things to do in Modesto -- golf courses, public parks, antique malls and museums abound -- the lack of clean air puts a damper on these outdoor activities. Modesto also inspired the film “American Graffiti” and hosts an annual “American Graffiti” car show. But because the Modesto-Merced area is beset with geographical and weather-related challenges, there’s little strategy available to improve air quality. According to the Huffington Post, “Air-pollution officials say the technology doesn’t yet exist to lessen the valley’s pollution and bring the region into compliance, though the district is investing in research and giving grants for things such as the new generation of battery-powered leaf blowers and lawn mowers.”

Related: Learn more about visiting Modesto, California.

5. El Centro, California

El Centro perches just north of the U.S.-Mexico border. According to Desert U.S.A., it’s the largest city in the country that’s below sea level, and it typically receives less than about three inches of rain every year. It maintains temperatures in the 70s and 80s throughout the winter, making it a great holiday destination. Sadly, the city’s climate exacerbates any air-quality issues. CNN Money reports that the city covers any dirt roads and farm drives with water or crushed asphalt to prevent flying dust. Traffic from Mexico also contributes to air pollution there. Furthermore, Mexico, its neighbor, has more lenient air-quality laws than the U.S., leaving El Centro vulnerable to any polluted air that drifts in.

4. Los Angeles, California

Los Angeles. The City of Angels. Home to Hollywood, the Walk of Fame and Universal Studios. The city’s history in the entertainment industry is well known. What many people don’t know about Los Angeles, however, is that it had a robust streetcar and public transportation system in the 1940s. The city was swindled during the “great American streetcar scandal,” in which a shell company made up of General Motors, Firestone Tire, Standard Oil and other corporate interests purchased existing streetcar systems and converted them into bus operations. It is surmised that the companies had forecasted a growing population and realized that a great deal of money could be made on oil and tires if Los Angeles remained dependent on oil -- and it has. According to ABC News, the American Lung Association urges people living in the Los Angeles-Long Beach area to reduce pollution by driving less, reducing electricity use and not burning wood or trash.

3. Fresno, California

Fresno is known as the “Asthma Capital of California.” Along with Bakersfield and Modesto, the city’s Central Valley geography makes pollution an ongoing problem. Tourists often pass through the city on their way to Yosemite to enjoy such attractions as the 4.5-acre historical Forestiere Underground Gardens that are reminiscent of catacombs. While the Fresno-Madera area’s natural beauty is augmented by its proximity to famous natural parks, air quality remains a threat. It seems that there’s little that Fresno can do to improve air quality, unless the city is willing to shell out advertising dollars promoting car shares and burn bans during the drought months.

2. Visalia, California

Nicknamed “America’s Salad Bowl,” the Visalia-Porterville-Hanford area of California houses a fertile agricultural valley in which farming is a major industry. According to its travel website, Visit Visalia, it’s the gateway to the Sequoia and Kings Canyon National Parks. It’s an outdoor destination, tempting visitors to hike, bike, raft and snowshoe. Unfortunately, its bowl-like topography makes it a trap for air pollutants arising from farming, oil drilling and traffic on Highway 99 and Interstate 5, according to The Guardian. Bonnie Holmes-Gen recently told Visalia Times-Delta that the transportation sector needs to “move away from internal combustion engines” in order to improve the air quality there.

1. Bakersfield, California

Bakersfield is situated in California’s Central Valley area just south of the pristine Sierra Nevada Mountain range. The area contributes greatly to California’s economy: It generates 76 percent of the state’s oil supply as well as a large amount of agriculture. The Hart Memorial Park features a family of peacocks roaming in vibrant display and hosts outdoor music events each Thursday. However, the geography of Bakersfield makes keeping the air free of pollutants a challenge because its valley “creates a bowl that traps air pollution,” reports Time magazine. According to a press release from the Sierra Club, Bakersfield can further improve air quality by reducing pollution and passing laws to discourage “a polluting, publicly subsidized, coal-fueled fertilizer and chemical plant.”

Related: Learn more about visiting Bakersfield, California.

What Do YOU Think?

Do you live in one of these cities? What do you do to stay active while avoiding the poor air quality? What have you noticed your city do to improve conditions, and what would you like to see them do?

And make sure you check out the 50 U.S. cities ranked as having the best air quality.

Related: The 50 Best Cities Ranked by Air Quality