SmogRank / History / September 18, 2023

Most polluted cities on September 18, 2023

1,895 cities ranked by their average PM2.5 over the day; the worst was Piedras Negras, Mexico, at 986.0 µg/m³. Each city's own local calendar day.

← Piedras Negras 986.0 µg/m³ 900 µg/m³15 WHO 24-hour guideline
Every city ranked for September 18, 2023, one column each, worst on the left and cleanest on the right; height is PM2.5 in µg/m³. Point at it to read a city; tap to open it.
  1. 1Piedras NegrasCoahuila, Mexico
    500+65.7×
  2. 2Tha BoNong Khai, Thailand
    500+50.8×
  3. 3Fort McMurrayAlberta, Canada
    1715.6×
  4. 4Puerto VarasLos Lagos Region, Chile
    1665.1×
  5. 5SaskatoonSaskatchewan, Canada
    1655.0×
  6. 6EdmontonAlberta, Canada
    1634.8×
  7. 7OsornoLos Lagos Region, Chile
    1554.1×
  8. 8Prince AlbertSaskatchewan, Canada
    1543.9×
  9. 9Puerto MonttLos Lagos Region, Chile
    1513.7×
  10. 10La UniónLos Ríos Region, Chile
    1443.5×
  11. 11Red DeerAlberta, Canada
    1383.4×
  12. 12ReginaSaskatchewan, Canada
    1343.3×
  13. 13NacimientoBiobio, Chile
    1273.1×
  14. 14St. AlbertAlberta, Canada
    1222.9×
  15. 15LimaLima Province, Peru
    1202.9×
  16. 16DushanbeDushanbe, Tajikistan
    1162.8×
  17. 17CoyhaiqueAysén, Chile
    1142.7×
  18. 18AstanaAstana, Kazakhstan
    1132.7×
  19. 19Dhakalow-cost sensorsDhaka Division, Bangladesh
    1102.6×
  20. 20Sherwood ParkAlberta, Canada
    1092.6×
  21. 20Santa Anita - Los FicusLima region, Peru
    1092.6×
  22. 22Puente AltoSantiago Metropolitan, Chile
    1052.5×
  23. 23TemucoAraucania, Chile
    1032.4×
  24. 23RedmondOregon, United States
    1032.4×
  25. 25San Salvador TizatlalliMéxico, Mexico
    1022.4×
  26. 26MexicaliBaja California, Mexico
    1012.4×
  27. 27Şabāḩ as SālimMubārak al Kabīr, Kuwait
    1012.4×
  28. 28SantiagoSantiago Metropolitan, Chile
    1002.4×
  29. 29RengoO'Higgins Region, Chile
    992.3×
  30. 30XonacatlánMéxico, Mexico
    972.2×
  31. 31Puerto AysénAysén, Chile
    952.2×
  32. 32TolucaMéxico, Mexico
    942.2×
  33. 33HanoiHanoi, Vietnam
    942.1×
  34. 34Villa Poeta José Gálvez BarrenecheaLima region, Peru
    932.1×
  35. 35ValdiviaLos Ríos Region, Chile
    922.1×
  36. 36Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    912.0×
  37. 37PristinaPristina, Kosovo
    902.0×
  38. 38RancaguaO'Higgins Region, Chile
    902.0×
  39. 39CoronelBiobio, Chile
    892.0×
  40. 40BamakoBamako, Mali
    881.9×
  41. 41Kansas CityKansas, United States
    881.9×
  42. 42San Francisco TlalcilalcalpanMéxico, Mexico
    871.9×
  43. 42ToméBiobio, Chile
    871.9×
  44. 44San Francisco De BorjaLima region, Peru
    861.9×
  45. 45HualquiBiobio, Chile
    861.9×
  46. 46Little RockArkansas, United States
    861.8×
  47. 47TalaganteSantiago Metropolitan, Chile
    851.8×
  48. 48BeijingBeijing, China
    851.8×
  49. 49Addis AbabaAddis Ababa, Ethiopia
    841.8×
  50. 50OlatheKansas, United States
    841.8×
  51. 50BendOregon, United States
    841.8×
  52. 52TalcahuanoBiobio, Chile
    841.8×
  53. 52CuranilahueBiobio, Chile
    841.8×
  54. 54Swift CurrentSaskatchewan, Canada
    831.8×
  55. 55SarajevoFederation of B&H, Bosnia and Herzegovina
    821.7×
  56. 56San CarlosÑuble, Chile
    821.7×
  57. 57NairobiNairobi County, Kenya
    811.7×
  58. 58QuillotaValparaiso, Chile
    811.7×
  59. 59QuinteroValparaiso, Chile
    811.7×
  60. 59TopekaKansas, United States
    811.7×
  61. 61ShenyangLiaoning, China
    801.6×
  62. 62CoquimboCoquimbo Region, Chile
    791.6×
  63. 63Lahorelow-cost sensorsPunjab, Pakistan
    791.6×
  64. 64AntananarivoAnalamanga, Madagascar
    791.6×
  65. 65KolkataWest Bengal, India
    791.6×
  66. 65TrnavaTrnava Region, Slovakia
    791.6×
  67. 67Samut SakhonSamut Sakhon, Thailand
    781.6×
  68. 67ConcepciónBiobio, Chile
    781.6×
  69. 69Saint JosephMissouri, United States
    781.6×
  70. 70AricaArica y Parinacota Region, Chile
    781.6×
  71. 71NaplesCampania, Italy
    771.6×
  72. 71BirminghamAlabama, United States
    771.6×
  73. 73Prince GeorgeBritish Columbia, Canada
    771.5×
  74. 74ChiguayanteBiobio, Chile
    761.5×
  75. 74AntofagastaAntofagasta, Chile
    761.5×
  76. 76OmahaNebraska, United States
    761.5×
  77. 77ArlesProvence-Alpes-Côte d'Azur, France
    751.5×
  78. 78Grande PrairieAlberta, Canada
    751.5×
  79. 79Kaseda-shirakameKagoshima, Japan
    751.5×
  80. 79AlgiersAlgiers, Algeria
    751.5×
  81. 81MarseilleProvence-Alpes-Côte d'Azur, France
    741.4×
  82. 81Los ÁngelesBiobio, Chile
    741.4×
  83. 83NagaiYamagata, Japan
    741.4×
  84. 83Fos-sur-MerProvence-Alpes-Côte d'Azur, France
    741.4×
  85. 83TalcaMaule Region, Chile
    741.4×
  86. 83West MemphisArkansas, United States
    741.4×
  87. 87Salon-de-ProvenceProvence-Alpes-Côte d'Azur, France
    741.4×
  88. 87GuadalajaraJalisco, Mexico
    741.4×
  89. 89SalorTashkent Region, Uzbekistan
    731.4×
  90. 89CuernavacaMorelos, Mexico
    731.4×
  91. 89ConcónValparaiso, Chile
    731.4×
  92. 89ChillánÑuble, Chile
    731.4×
  93. 93BartlettTennessee, United States
    731.4×
  94. 94Kansas CityMissouri, United States
    721.4×
  95. 94CalgaryAlberta, Canada
    721.4×
  96. 96CuricóMaule Region, Chile
    721.4×
  97. 97CopiapóAtacama, Chile
    721.4×
  98. 97IndioCalifornia, United States
    721.4×
  99. 99KushikinoKagoshima, Japan
    711.3×
  100. 99NiceProvence-Alpes-Côte d'Azur, France
    711.3×
  101. 99SpringfieldMissouri, United States
    711.3×
  102. 102SendaiKagoshima, Japan
    711.3×
  103. 103KaliszGreater Poland, Poland
    711.3×
  104. 103DerbyKansas, United States
    711.3×
  105. 105GuangzhouGuangdong, China
    701.3×
  106. 105BellevueNebraska, United States
    701.3×
  107. 107SpringdaleArkansas, United States
    701.3×
  108. 107San Pedro de la PazBiobio, Chile
    701.3×
  109. 109SenicaTrnava Region, Slovakia
    701.3×
  110. 109GdyniaPomerania, Poland
    701.3×
  111. 111Ciudad NezahualcoyotlMéxico, Mexico
    701.3×
  112. 111CauquenesMaule Region, Chile
    701.3×
  113. 113Ciudad ApodacaNuevo León, Mexico
    701.3×
  114. 114OlomoucOlomouc Region, Czechia
    691.3×
  115. 114GdańskPomerania, Poland
    691.3×
  116. 114BydgoszczKujawsko-Pomorskie, Poland
    691.3×
  117. 114AnconaThe Marches, Italy
    691.3×
  118. 114LibertyMissouri, United States
    691.3×
  119. 119OstravaMoravian-Silesian Region, Czechia
    691.3×
  120. 120N'DjamenaN’Djaména, Chad
    691.3×
  121. 120MinamikyushuKagoshima, Japan
    691.3×
  122. 122OlsztynWarmia-Masuria, Poland
    691.2×
  123. 122Falconara MarittimaThe Marches, Italy
    691.2×
  124. 122HernandoMississippi, United States
    691.2×
  125. 125HonmachiKumamoto, Japan
    691.2×
  126. 126La SerenaCoquimbo Region, Chile
    691.2×
  127. 127Karachilow-cost sensorsSindh, Pakistan
    681.2×
  128. 127VeszprémVeszprém, Hungary
    681.2×
  129. 127RadomskoŁódź Voivodeship, Poland
    681.2×
  130. 127Alto HospicioTarapacá, Chile
    681.2×
  131. 127WichitaKansas, United States
    681.2×
  132. 132NakatsuOita, Japan
    681.2×
  133. 133Almatylow-cost sensorsAlmaty, Kazakhstan
    681.2×
  134. 133LunelOccitanie, France
    681.2×
  135. 133KutnoŁódź Voivodeship, Poland
    681.2×
  136. 136NîmesOccitanie, France
    681.2×
  137. 136MontpellierOccitanie, France
    681.2×
  138. 136AvignonProvence-Alpes-Côte d'Azur, France
    681.2×
  139. 136RaymoreMissouri, United States
    681.2×
  140. 140RacibórzSilesia, Poland
    671.2×
  141. 140AberdeenSouth Dakota, United States
    671.2×
  142. 140KirishimaKagoshima, Japan
    671.2×
  143. 143TakasakiGunma, Japan
    671.2×
  144. 143GapProvence-Alpes-Côte d'Azur, France
    671.2×
  145. 143PardubicePardubice Region, Czechia
    671.2×
  146. 143JesiThe Marches, Italy
    671.2×
  147. 143LotaBiobio, Chile
    671.2×
  148. 148HyderabadTelangana, India
    671.2×
  149. 148CannesProvence-Alpes-Côte d'Azur, France
    671.2×
  150. 150Mexico CityMexico City, Mexico
    671.2×
  151. 151Islamabadlow-cost sensorsIslamabad, Pakistan
    671.2×
  152. 151Aix-en-ProvenceProvence-Alpes-Côte d'Azur, France
    671.2×
  153. 151PoznańGreater Poland, Poland
    671.2×
  154. 151East Saint LouisIllinois, United States
    671.2×
  155. 155MonacoMunicipality of Monaco, Monaco
    661.2×
  156. 155Hradec KrálovéHradec Králové Region, Czechia
    661.2×
  157. 155KrakówLesser Poland, Poland
    661.2×
  158. 155Naucalpan de JuárezMéxico, Mexico
    661.2×
  159. 159Fort SmithArkansas, United States
    661.2×
  160. 160ŁaskŁódź Voivodeship, Poland
    661.1×
  161. 161ŽideniceSouth Moravian, Czechia
    661.1×
  162. 161ToruńKujawsko-Pomorskie, Poland
    661.1×
  163. 161TlaquepaqueJalisco, Mexico
    661.1×
  164. 161SalamancaGuanajuato, Mexico
    661.1×
  165. 165VitrollesProvence-Alpes-Côte d'Azur, France
    661.1×
  166. 165SalernoCampania, Italy
    661.1×
  167. 165BolzanoTrentino-Alto Adige, Italy
    661.1×
  168. 165TocopillaAntofagasta, Chile
    661.1×
  169. 169MartinŽilina Region, Slovakia
    661.1×
  170. 169BeneventoCampania, Italy
    661.1×
  171. 171MinamataKumamoto, Japan
    651.1×
  172. 172KagoshimaKagoshima, Japan
    651.1×
  173. 172Valašské MeziříčíZlín, Czechia
    651.1×
  174. 174PřerovOlomouc Region, Czechia
    651.1×
  175. 174Canvey IslandEngland, United Kingdom
    651.1×
  176. 176DębicaSubcarpathia, Poland
    651.1×
  177. 176ChennaiTamil Nadu, India
    651.1×
  178. 176MiyakonojōMiyazaki, Japan
    651.1×
  179. 176KłodzkoLower Silesia, Poland
    651.1×
  180. 176KatowiceSilesia, Poland
    651.1×
  181. 176Ponca CityOklahoma, United States
    651.1×
  182. 182BiałystokPodlasie, Poland
    651.1×
  183. 182ToulonProvence-Alpes-Côte d'Azur, France
    651.1×
  184. 182TrentoTrentino-Alto Adige, Italy
    651.1×
  185. 185Bishkeklow-cost sensorsBishkek, Kyrgyzstan
    641.1×
  186. 185NitraNitra Region, Slovakia
    641.1×
  187. 185FlorenceTuscany, Italy
    641.1×
  188. 185CapannoriTuscany, Italy
    641.1×
  189. 185Viña del MarValparaiso, Chile
    641.1×
  190. 190KobayashiMiyazaki, Japan
    641.1×
  191. 190PécsBaranya, Hungary
    641.1×
  192. 190Ciudad Benito JuárezNuevo León, Mexico
    641.1×
  193. 190BrunswickGeorgia, United States
    641.1×
  194. 194ThessaloníkiCentral Macedonia, Greece
    641.1×
  195. 194KandaFukuoka, Japan
    641.1×
  196. 194West FargoNorth Dakota, United States
    641.1×
  197. 194BrookingsSouth Dakota, United States
    641.1×
  198. 198EsztergomKomárom-Esztergom, Hungary
    641.1×
  199. 198São PauloSão Paulo, Brazil
    641.1×
  200. 200TarnówLesser Poland, Poland
    631.1×

Top 200 of 1,895 shown.

Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

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SmogRank, most polluted cities, PM2.5, September 18, 2023, smogrank.com/history/2023-09-18 (accessed 2 Oct 2026).

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