World's most polluted cities 2019 (PM2.5)
The most polluted cities according to data aggregated from over 60,000 data points.
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2019
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2019 Report - English
2019 World air quality report
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PM2.5 Legend 
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Unit: µg/m³
| Rank | City | 2019 AVG | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | 2018 AVG | 2017 AVG |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  Nakhon Ratchasima, Thailand | 42.2 | 42.1 | 67.9 | 68 | 41.4 | 28.3 | 17.1 | 15.7 | - | - | - | - | 32.6 | 37.6 | - |
| 2 | Saraphi, Thailand | 41.3 | 45.5 | 57.4 | 116.9 | 84.4 | 38.1 | 13 | 12.5 | 12.7 | 20.2 | 22.7 | 31.5 | 44.8 | - | - |
| 3 | Pai, Thailand | 38.9 | 24.8 | 65.3 | 141.4 | 120.3 | 34.8 | 6.1 | 5.4 | 5.4 | 11.9 | 12.1 | 16.3 | 27 | 29.4 | - |
| 4 | Hang Dong, Thailand | 38 | 41.8 | 63.4 | 99.4 | 78.7 | 37 | 8.7 | 8.8 | 9.9 | 17.1 | 19.5 | 28.3 | 45.4 | - | - |
| 5 | Chiang Rai, Thailand | 37 | 28 | 40.5 | 113.8 | 99.3 | 57.7 | 10.4 | 7.6 | 7.2 | 14.5 | 15.7 | 20.1 | 29.9 | - | - |
| 6 | Mae Rim, Thailand | 36.9 | 25 | 46.7 | 100.4 | 71.6 | 39.3 | 14.7 | 15.2 | 14.6 | 19.7 | 19 | 26.1 | 37.2 | - | - |
| 7 | Mueang Lamphun, Thailand | 36.9 | 56.6 | 57.6 | 76.7 | 64.8 | 34.2 | 11.6 | 11.1 | 12.2 | 21.2 | 22.5 | 28.1 | 49.7 | - | - |
| 8 | Khon Kaen, Thailand | 36.4 | 51.6 | 67.2 | 68.6 | 41.5 | 29.2 | 17.4 | 16.9 | 15.8 | 29.6 | 26.3 | 31.4 | 42.6 | - | - |
| 9 | Mueang Mae Hong Son, Thailand | 35.3 | 29.4 | 46.8 | 116.1 | 99.7 | 21.3 | 11.5 | 5.9 | 4.7 | 10.1 | 9.5 | 13.1 | 24.6 | - | - |
| 10 | Si Samrong, Thailand | 34.6 | - | - | 93.4 | 58.9 | 25.5 | 10.2 | 11.2 | 9.6 | 24.5 | 27.8 | 36.4 | 62.1 | - | - |
| 11 | Chaloem Phra Kiat, Thailand | 34.4 | 65.9 | 50.6 | 42.5 | 27.2 | 24.6 | 20.6 | 17.7 | 16.3 | 30.2 | 35.5 | 42.8 | 51.3 | - | - |
| 12 | Ban Pong, Thailand | 33.6 | 27.5 | 46.9 | 100.5 | 79.3 | 40.7 | 7.4 | 7.2 | 6.9 | 14.3 | 15.6 | 21.4 | 34.6 | - | - |
| 13 | Lampang, Thailand | 33.1 | 75.6 | 62.1 | 78.1 | 58.2 | 27.8 | 11.2 | 11.2 | 9 | 18.7 | 20.8 | 25.5 | 43.6 | 23.3 | 19.5 |
| 14 | Tron, Thailand | 33 | - | - | 99.8 | 57.3 | 33.9 | 10.3 | 10 | 8.1 | 18.4 | 20.8 | 31.1 | 64.8 | - | - |
| 15 | Chaloem Phra Kiat, Thailand | 32.8 | 17.5 | 37.6 | 93.2 | 92.7 | 39.1 | 10.3 | 7.2 | 4.9 | 17.1 | 12.4 | 13.6 | 24.9 | - | - |
| 16 | Chiang Mai, Thailand | 32.3 | 24.4 | 47.2 | 98.7 | 74.1 | 33.6 | 7.8 | 6.8 | 7.9 | 15.8 | 16.8 | 23 | 33.1 | 24.5 | 22.7 |
| 17 | Phrae, Thailand | 31.3 | 46.2 | 62.9 | 73.1 | 47.4 | 31.2 | 8.3 | 7.1 | 7.5 | 16.3 | 16.7 | 23.3 | 42.9 | - | - |
| 18 | Mueang Nan, Thailand | 30.9 | 27.3 | 47.6 | 80.6 | 59 | 33.4 | 11.6 | 11.3 | 7.3 | 16.9 | 13.9 | 17.8 | 30.6 | - | - |
| 19 | Phutthamonthon, Thailand | 30.3 | - | - | 37.8 | 25.4 | 26.3 | 15.4 | 15.2 | 11.1 | 28.4 | 35.5 | 51.8 | 58.6 | - | - |
| 20 | Mae Mo, Thailand | 30.2 | 37.2 | 59 | 72.5 | 57.5 | 35.5 | 9.8 | 9 | 7.8 | 14.2 | 12.9 | 15.9 | 33.6 | - | - |
| 21 | Krathum Baen, Thailand | 29.7 | 64.2 | 28.2 | 29.1 | 22.3 | 27.5 | 21.4 | 18.7 | 18.2 | 27.4 | 31.5 | 41.5 | 47.3 | - | - |
| 22 | Ratchaburi, Thailand | 29.5 | 78.5 | 34.1 | 32.4 | 19 | 23.8 | 20.2 | 17.2 | 10.2 | 15.1 | 24.2 | 40.7 | 53.8 | 32.2 | 22.4 |
| 23 | Bang Khonthi, Thailand | 28.4 | - | - | 34.3 | 23.9 | 22.5 | 11.8 | 11.9 | 9.4 | 23.2 | 32.7 | 54.8 | 62.5 | - | - |
| 24 | Mae Sot, Thailand | 27.6 | 59.4 | 51.4 | 53.1 | 48.6 | 22.4 | 9.1 | 7.9 | 7.3 | 14.9 | 15 | 22 | 46.9 | 32.2 | 23.2 |
| 25 | Phra Pradaeng, Thailand | 27.1 | 61.6 | 29.4 | 32 | 24.6 | 26.4 | 17.2 | 16.5 | 13.2 | 24.9 | 26.8 | 33.3 | 37.2 | - | - |
| 26 | Na Wang, Thailand | 26.8 | - | - | 96.4 | 42.1 | 24.6 | 11.5 | 9.4 | 7.8 | 21.6 | 20.2 | 21.2 | 33.6 | - | - |
| 27 | Samut Songkhram, Thailand | 26.3 | - | 27.2 | 34.9 | 23.7 | 20 | 9.5 | 10.5 | 7.5 | 21.2 | 28.5 | 48 | 58.7 | - | - |
| 28 | Pathum Thani, Thailand | 26.2 | - | 32.3 | 32.5 | 22.9 | 24.6 | 12.9 | 11.6 | 9 | 24.3 | 29.2 | 38.6 | 50.9 | - | - |
| 29 | Tha Bo, Thailand | 25.4 | 44.5 | 78.5 | 36.2 | 21.9 | 7.9 | 5.5 | 5 | 4.4 | - | - | - | - | 37.2 | - |
| 30 | Kanchanaburi, Thailand | 25.2 | 74.4 | 44.7 | 43.6 | 29.4 | 16 | 6.3 | 7.4 | 6.2 | 15.8 | 19.1 | 30.1 | 49.2 | 24.9 | - |
| 31 | Thanyaburi, Thailand | 24.9 | - | - | 37.7 | 24.5 | 24.4 | 13.7 | 10.6 | 8.5 | 24.5 | 28.4 | 37.4 | 49 | - | - |
| 32 | Si Maha Phot, Thailand | 24.8 | 55.6 | 35.4 | 32.7 | 22.6 | 22.8 | 15.1 | 15.6 | 13.1 | 17.9 | 20.4 | 26.4 | 36.6 | 30.9 | 30.1 |
| 33 | Phra Nakhon Si Ayutthaya, Thailand | 24.6 | 54.9 | 32 | 31.6 | 23 | 20.3 | 11.9 | 11.8 | 10.3 | 19.8 | 22.3 | 30.3 | 41.7 | - | - |
| 34 | Chiang Saen, Thailand | 24.4 | - | - | - | 88.2 | 71.2 | 11.3 | 7.4 | 7.6 | 18.3 | 18.3 | 19.5 | 28.4 | - | - |
| 35 | Pak Kret, Thailand | 24.2 | 35.4 | 23 | 27.2 | 25.1 | 21.5 | 11.9 | 11.2 | 8.6 | 21.2 | 25.5 | 35.5 | 47.1 | - | - |
| 36 | Tha Yang, Thailand | 24.2 | - | - | 37 | 24.7 | 18.1 | 9.8 | 10.1 | 7.8 | 18.2 | 26.6 | 42.7 | 50.3 | - | - |
| 37 | Bang Phli, Thailand | 24.2 | 54.2 | 19.8 | 27.3 | 19.4 | 21.6 | 9.2 | 10.3 | 7.5 | 21.7 | 25 | 34.1 | 39.8 | - | - |
| 38 | Samut Sakhon, Thailand | 24.1 | 102.9 | 21.1 | 22.8 | 18.1 | 21 | 9.3 | 10.4 | 6.8 | 23.6 | 28.2 | 41.9 | 44.2 | 39.8 | 26.9 |
| 39 | Nakhon Sawan, Thailand | 23.9 | 53.4 | 43.3 | 50.6 | 32.1 | 20.2 | 9.7 | 10 | 8.4 | 16.1 | 19 | 21 | 28.4 | - | - |
| 40 | Kamphaeng Phet, Thailand | 23.6 | - | - | - | 49.3 | 20.8 | 7.9 | 7.8 | 7.1 | 17.6 | 18.7 | 25.5 | 60.5 | - | - |
| 41 | Udon Thani, Thailand | 23.4 | - | - | - | 44.9 | 27.1 | 12 | 10.2 | 7 | 22 | 23.9 | 28.4 | 40.5 | - | - |
| 42 | Nonthaburi, Thailand | 23.2 | 70.6 | 29.4 | 29.4 | 19.1 | 19.2 | 9.5 | 10.1 | 7.6 | 21.2 | 25.1 | 32.9 | 38.9 | - | - |
| 43 | Lam Luk Ka, Thailand | 23.2 | - | 28.6 | 34.5 | 25 | 22.8 | 14.1 | 11.7 | 8.7 | 21.3 | 23.5 | 29.5 | 39.1 | - | - |
| 44 | Bang Lamung, Thailand | 23 | - | - | 29.9 | 20.4 | 22.3 | 10.2 | 10.2 | 8.1 | 19.1 | 26.6 | 40.5 | 42.8 | - | - |
| 45 | Bang Kruai, Thailand | 23 | 55.6 | 23 | 24.3 | 20 | 19.5 | 12.2 | 13.9 | 11 | 22.9 | 23.4 | 29 | 37.2 | - | - |
| 46 | Khlong Luang, Thailand | 23 | 85.4 | 30 | 30.5 | 24 | 22.4 | 12.9 | 11.2 | 9.1 | 20.4 | 23.9 | 33.1 | 36.8 | - | - |
| 47 | Samut Prakan, Thailand | 22.9 | 60 | 21.8 | 25.5 | 19.3 | 21.6 | 10.2 | 11.7 | 8.9 | 24.1 | 27 | 32.9 | 37.7 | 32.2 | 33.2 |
| 48 | Bangkok, Thailand | 22.8 | 47.4 | 24.1 | 27.7 | 19 | 19.6 | 9.4 | 10.2 | 7.6 | 20.4 | 23.2 | 30.2 | 34.2 | 25.2 | 27.6 |
| 49 | Saraburi, Thailand | 22.7 | 51.9 | 35.2 | 32.9 | 22 | 20.8 | 10.8 | 11.2 | 8.9 | 18.8 | 19.1 | 20.3 | 42.7 | - | - |
| 50 | Bang Sao Thong, Thailand | 22.6 | 61.2 | 23.3 | 22.3 | 17.2 | 19 | 13.5 | 15.3 | 12.9 | 22.7 | 26.9 | 32.5 | 28 | - | - |
