The most polluted cities in the world, ranked

  • According to the World Health Organization, the air in these 50 cities was found to be the most polluted in 2018. 

    Air-quality monitoring devices worldwide tracked levels of dangerous particulates. The most harmful kind, called PM2.5, contains tiny particles small enough to enter the bloodstream through the lungs—a problem that contributes to an estimated 7 million premature deaths every year.

    We’ve ranked the cities here, from least to most polluted.

    Credit: Aly Song/Reuters

  • Twelve years ago, Linfen was the most polluted city in the world, but even then, Beijing was making efforts to curb the city’s coal-burning addiction. 

    Nearly 200 coal-fired boilers were decommissioned, and natural gas heaters replaced coal ones in local homes.

    Credit: Peter Parks/AFP/Getty Images

  • Emissions from oil refineries and dust from the desert both contribute to the poor air quality in Yanbu.

    Credit: Google Street View

  • This city in eastern China is one of the country’s biggest coal producers.

    Credit: Getty Images

  • In 2018, the annual mean for fine particulate matter in Weinan was 76 micrograms per cubic meter, more than seven times the World Health Organization’s target value.

    Credit: / Getty Images

  • Shangqiu is 179 miles east of Pingdingshan in China’s Henan province. 

    It is traditionally a farming city, but some modern industry, like this textile factory, has been developed in Shangqiu since the 1990s.

    Credit: Str / AFP/Getty Images

  • This city is a manufacturing hub. Paper, leather, textiles, cigarettes and electronics are all produced here. The city is most famous for its massive ham-processing plant.

    Credit: VCG

  • Credit: VCG / Getty Images

  • Shouguang is an agricultural hub in China’s Shandong province. 

    Credit: Fred Dufour/AFP/Getty Images

  • This photo shows smoke from a fire at a local oil refinery. Oil production and processing plants can release greenhouse gases and dangerous particulate pollutants.

    Credit: Yasser Al-zayyat / AFP/Getty Images

  • Teams compete during the Dragon Boat Festival in Luoyang. The city’s skyline is shrouded in smog.

    Credit: Str / AFP/Getty Images

  • This photo shows a damaged oil rig off the coast of Dongying in Shandong province. In 2017, Beijing shut down 30 oil refineries in the province to decrease industrial air pollution.

    Credit: Str / AFP/Getty Images

  • The Health Effects Institutes’ State of Global Air survey showed that the entire population of Bangladesh — around 168 million people — has been consistently exposed to unhealthy levels of fine particulates in the air since 1990.

    Credit: Afp / AFP/Getty Images

  • A traffic policeman directs drivers on a heavy smog day in Zaozhuang.

    Credit: VCG / Getty Images

  • A farmer rides a bike down a country road on a hazy day in Dezhou. In 2007, Himin Solar Energy Group began to develop Dezhou into a hub for renewable-energy tech companies.

    Credit: Frederic J. Brown/AFP/Getty Images

  • A train emerges from the haze during the annual Bishwa Ijterna gathering of Muslim devotees.

    Credit: Allison Joyce / Getty Images

  • This aerial photo shows the weather in a residential area in nearby Xian.

    Credit: Fred Dufour/AFP/Getty Images

  • Jining borders two other cities on this list, Zaozhuang and Heze.

    Credit: Google Street View

  • This city in northeastern China has the Yellow River as its northern border.

    Credit: Str/AFP/Getty Images

  • These workers are testing a dust-suppression truck. This water cannon purports to suppress smog and promote clear, healthy air.

    Credit: ChinaFotoPress/VCG/Getty Images

  • Nagpur, home to the Marbat festival, is the most polluted city in the Indian state of Maharashtra.

    Credit: Str/AFP/Getty Images

  • The Xinxiang Environmental Protection Volunteers Association helped to close more than 100 factories in the area between 2001 and 2009. The effort was an attempt to clean up the air and water in central China.

    Credit: Peter Parks/AFP/Getty Images

  • The sun is barely visible through the smog in this photo of Bangladeshi laborers working at a brick factory in Khulna.

    Credit: Munir Uz Zaman/AFP/Getty Images

  • Workers from the Longfeng leather and fur factory cart material through the streets of Jiaozuo.

    Credit: Getty Images

  • An orange alert for heavy smog was issued on this hazy December day in Liaocheng.

    Credit: VCG/VCG via Getty Images

  • Onlookers watch as a plane performs tricks at the Anyang International Aviation Sports Tourism Festival.

    Credit: VCG / Getty Images

  • In 2016, the industrial steel city of Xingtai ranked as China’s most polluted.

    Credit: Ed Jones/AFP/Getty Images

  • This chemical factory in Hengshui might feed Hebei province’s booming economy, but it also contributes to the region’s air problems, according to pollution researchers.

    Credit: Fred Dufour/AFP/Getty Images

  • Karachi is home to a large percentage of Pakistan’s manufacturing industry.

    Credit: Rizwan Tabassum/AFP/Getty Images

  • Some schools have snow days, but schools in Shijiazhuang have the occasional smog day.

    Credit: Greg Baker/AFP/Getty Images

  • Young students wear face masks on a red-alert smog day in Jinan.

    Credit: Str / AFP/Getty Images

  • As recently as 2019, children have been evacuated from Mongolia’s capital due to the toxic air conditions. 

    Grandparents and other family members take vulnerable young people to rural Mongolia — or to nearby countries — to escape the negative health impacts of breathing the air in Ulaanbaatar.

    Credit: Byambasuren Byamba-ochir/AFP/Getty Images

  • Chimneys cloud the skyline of Baoding. Coal is used to power the city and surrounding villages. It ranks as China’s most polluted city.

    Credit: Ed Jones/AFP/Getty Images

  • Bangladeshi travelers cross the Shitalakhya River. The banks in the distance are obscured by pollution from the bustling brick-manufacturing industry.

    Credit: MUNIR UZ ZAMAN/AFP/Getty Images

  • The old Blue City of Jodhpur is a popular tourist destination. But a lack of rain contributes to its poor air quality.

    Credit: Emmanuel Dunand/AFP/Getty Images

  • Laborers harvest wheat in this city in the Indian state of Punjab.

    Credit: Str/AFP/Getty Images

  • Ugandan military police patrol a street in Kampala in 2016. Pollution researchers have cited vehicle emissions as a leading cause of air pollution in Kampala.

    Credit: Isaac Kasamani/AFP/Getty Images

  • Monkeys admire their reflections atop a motorcycle. The smog shrouds the city in the distance.

    Credit: Dominique Faget/AFP/Getty Images

  • This area of Pakistan is home to steel-rolling mills, leather tanning facilities, marble factories and oil refineries. All of these industries can, under certain conditions, negatively impact air quality. In this picture, a laborer is seen working at a brick kiln.

    Credit: Nicolas Asfouri/AFP/Getty Images

  • Another black cloud rises from a brick factory.

    Credit: A Majeed/AFP/Getty Images

  • According to a 2017 study by the British medical journal Lancet, more than 33 percent of deaths in the Indian state of Bihar, where Muzaffarpur is located, were caused by pollution-related diseases during the previous calendar year.

    Credit: Strdel/AFP/Getty Images

  • Many Fortune 500 companies, including Google and Intel, have offices in Gurugram, just southwest of New Delhi.

    Despite its position as a wealthy, white-collar business hub, the air quality in the city is still very poor. The annual mean for dangerous PM2.5 pollution is 12 times the World Health Organization’s recommended levels.

    Credit: Dominique Faget/AFP/Getty Images

  • Pollution haze is visible in this photo of the Taj Mahal. The particulate matter in Agra is caused primarily by the practice of burning of scrap tires to extract iron.

    Credit: Strdel/AFP/Getty Images

  • Unlike many of the world’s most polluted cities, deforestation and changing weather patterns are the primary explanation for this city’s poor air quality. It is the most polluted city outside of India.

    Credit: Rbairdpccam/Flickr

  • In response to growing pollution from vehicle emissions, Lucknow built a metro rail service. This photo shows the fanfare of the train’s inaugural run.

    Credit: Rajesh Kumar Singh/AP

  • The Indian capital was once the most polluted city in the world. The city still struggles with pollution from the burning of nearby rice paddies, burning municipal waste, and vehicle exhaust emissions.

    Credit: Sajjad Hussain/AFP/Getty Images

  • Hindu devotees return from a ceremony during Chhath Puja, a fall Hindu festival thanking the Sun God for sustaining life on earth. Thick smog obscures the sunset.

    Credit: Aftab Alam Siddiqui/AP

  • Varanasi is considered to be the spiritual capital of India. Dust from construction contributes to the poor air quality in the city.

    Credit: Prakash Singh/AFP/Getty Images

  • A train shines a light through heavy smog at a railway station in Gaya, a holy city in the Indian state of Bihar.

    Credit: Suman / AFP/Getty Images

  • The smog levels in Faridabad spike during winter, when cold temperatures trap pollutants close to the ground.

    Credit: Money Sharma/AFP/Getty Images

  • Workers pile buffalo hides to be made into leather at a tannery in Kanpur. Leather tanneries can release dangerous chromium into the air.

    Credit: Sanjay Kanojia/AFP/Getty Images

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