SmogRank / History / April 18, 2023

Most polluted cities on April 18, 2023

1,227 cities ranked by their average PM2.5 over the day; the worst was Piedras Negras, Mexico, at 351.0 µg/m³. Each city's own local calendar day.

Bad-air episodes during April 18, 2023. All episodes.

← Piedras Negras 351.0 µg/m³ 300 µg/m³15 WHO 24-hour guideline
Every city ranked for April 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+23.4×
  2. 2Kathmandulow-cost sensorsBagmati Province, Nepal
    1907.4×
  3. 3Dhakalow-cost sensorsDhaka Division, Bangladesh
    1836.7×
  4. 4San Mateo AtencoMéxico, Mexico
    1695.4×
  5. 5DushanbeDushanbe, Tajikistan
    1695.4×
  6. 6BeijingBeijing, China
    1634.8×
  7. 7DelhiDelhi, India
    1604.5×
  8. 8Bang Khun ThianBangkok, Thailand
    1594.5×
  9. 9HyderabadTelangana, India
    1584.4×
  10. 10BamakoBamako, Mali
    1564.1×
  11. 11TlaquepaqueJalisco, Mexico
    1413.5×
  12. 12Nong KhaemBangkok, Thailand
    1383.4×
  13. 13YangonYangon, Myanmar
    1363.3×
  14. 14BangkokBangkok, Thailand
    1333.2×
  15. 15Nakhon PathomNakhon Pathom, Thailand
    1323.2×
  16. 16Samut PrakanSamut Prakan, Thailand
    1253.0×
  17. 17Khlong LuangPathum Thani, Thailand
    1243.0×
  18. 18HanoiHanoi, Vietnam
    1212.9×
  19. 19Samut SakhonSamut Sakhon, Thailand
    1202.9×
  20. 20Phra PradaengSamut Prakan, Thailand
    1172.8×
  21. 21BaghdadBaghdad, Iraq
    1152.8×
  22. 21CholulaPuebla, Mexico
    1152.8×
  23. 23Mueang NonthaburiNonthaburi, Thailand
    1152.7×
  24. 24Bang KapiBangkok, Thailand
    1142.7×
  25. 25ManamaManama, Bahrain
    1112.6×
  26. 26Bang Bo DistrictSamut Prakan, Thailand
    1072.5×
  27. 27CelayaGuanajuato, Mexico
    1062.5×
  28. 28Puerto VarasLos Lagos Region, Chile
    1042.5×
  29. 29Tepeji del Río de OcampoHidalgo, Mexico
    1042.4×
  30. 30MumbaiMaharashtra, India
    1002.4×
  31. 31ShenyangLiaoning, China
    992.3×
  32. 31MexicaliBaja California, Mexico
    992.3×
  33. 33Puerto MonttLos Lagos Region, Chile
    962.2×
  34. 34DreuxCentre-Val de Loire, France
    952.2×
  35. 35Şabāḩ as SālimMubārak al Kabīr, Kuwait
    952.2×
  36. 36Ciudad Benito JuárezNuevo León, Mexico
    942.2×
  37. 37RouenNormandy, France
    942.1×
  38. 38EvergemFlanders, Belgium
    942.1×
  39. 39BeauvaisHauts-de-France, France
    932.1×
  40. 39HualpénBiobio, Chile
    932.1×
  41. 41GuangzhouGuangdong, China
    922.1×
  42. 41CuernavacaMorelos, Mexico
    922.1×
  43. 43JakartaJakarta, Indonesia
    922.1×
  44. 44ChartresCentre-Val de Loire, France
    922.1×
  45. 44CuranilahueBiobio, Chile
    922.1×
  46. 46LisieuxNormandy, France
    922.1×
  47. 47TolucaMéxico, Mexico
    912.1×
  48. 48NacimientoBiobio, Chile
    902.0×
  49. 49Le MansPays de la Loire, France
    902.0×
  50. 50RambouilletÎle-de-France, France
    902.0×
  51. 51LinaresMaule Region, Chile
    892.0×
  52. 52MenenFlanders, Belgium
    881.9×
  53. 52AngersPays de la Loire, France
    881.9×
  54. 54IzegemFlanders, Belgium
    881.9×
  55. 55ÉvreuxNormandy, France
    881.9×
  56. 55DieppeNormandy, France
    881.9×
  57. 55San Francisco TlalcilalcalpanMéxico, Mexico
    881.9×
  58. 58RoeselareFlanders, Belgium
    881.9×
  59. 59KortrijkFlanders, Belgium
    871.9×
  60. 59AlençonNormandy, France
    871.9×
  61. 59SantiagoSantiago Metropolitan, Chile
    871.9×
  62. 62ConakryConakry, Guinea
    871.9×
  63. 63Peshawarlow-cost sensorsKhyber Pakhtunkhwa, Pakistan
    861.9×
  64. 64RancaguaO'Higgins Region, Chile
    861.9×
  65. 65HualquiBiobio, Chile
    861.9×
  66. 66TournaiWallonia, Belgium
    861.8×
  67. 67ParisÎle-de-France, France
    851.8×
  68. 67TocopillaAntofagasta, Chile
    851.8×
  69. 69Le HavreNormandy, France
    851.8×
  70. 69Puente AltoSantiago Metropolitan, Chile
    851.8×
  71. 71La UniónLos Ríos Region, Chile
    851.8×
  72. 72TemucoAraucania, Chile
    851.8×
  73. 72QuinteroValparaiso, Chile
    851.8×
  74. 74ValdiviaLos Ríos Region, Chile
    851.8×
  75. 75ValenciennesHauts-de-France, France
    851.8×
  76. 75RennesBrittany, France
    851.8×
  77. 75CaenNormandy, France
    851.8×
  78. 78RoubaixHauts-de-France, France
    841.8×
  79. 79ToméBiobio, Chile
    841.8×
  80. 80TalcahuanoBiobio, Chile
    841.8×
  81. 81Sainte-Geneviève-des-BoisÎle-de-France, France
    831.8×
  82. 82KhartoumKhartoum, Sudan
    831.8×
  83. 82BakuBaki, Azerbaijan
    831.8×
  84. 84San CarlosÑuble, Chile
    831.8×
  85. 85XonacatlánMéxico, Mexico
    831.7×
  86. 86PueblaPuebla, Mexico
    831.7×
  87. 87Saint-QuentinHauts-de-France, France
    821.7×
  88. 87LilleHauts-de-France, France
    821.7×
  89. 89ColomboWestern Province, Sri Lanka
    821.7×
  90. 90Kinshasalow-cost sensorsKinshasa, Democratic Republic of the Congo
    821.7×
  91. 90ÉtampesÎle-de-France, France
    821.7×
  92. 90AmiensHauts-de-France, France
    821.7×
  93. 93Kampalalow-cost sensorsCentral Region, Uganda
    821.7×
  94. 94CoronelBiobio, Chile
    811.7×
  95. 95Ciudad NezahualcoyotlMéxico, Mexico
    811.7×
  96. 95OsornoLos Lagos Region, Chile
    811.7×
  97. 97CuricóMaule Region, Chile
    801.6×
  98. 97CopiapóAtacama, Chile
    801.6×
  99. 99MonsWallonia, Belgium
    801.6×
  100. 100BloisCentre-Val de Loire, France
    791.6×
  101. 101VannesBrittany, France
    791.6×
  102. 101RengoO'Higgins Region, Chile
    791.6×
  103. 101QuillotaValparaiso, Chile
    791.6×
  104. 104ChillánÑuble, Chile
    791.6×
  105. 105La SerenaCoquimbo Region, Chile
    791.6×
  106. 106Saint-BrieucBrittany, France
    781.6×
  107. 107AntofagastaAntofagasta, Chile
    781.6×
  108. 108ConcónValparaiso, Chile
    781.6×
  109. 109GentFlanders, Belgium
    771.6×
  110. 110Joué-lès-ToursCentre-Val de Loire, France
    771.5×
  111. 110San Andrés TuxtlaVeracruz, Mexico
    771.5×
  112. 112ZapopanJalisco, Mexico
    771.5×
  113. 113KoksijdeFlanders, Belgium
    771.5×
  114. 113NantesPays de la Loire, France
    771.5×
  115. 113GuadalajaraJalisco, Mexico
    771.5×
  116. 116TlaxcalaTlaxcala, Mexico
    761.5×
  117. 116CoquimboCoquimbo Region, Chile
    761.5×
  118. 118MaldegemFlanders, Belgium
    761.5×
  119. 118KrefeldNorth Rhine-Westphalia, Germany
    761.5×
  120. 120LorientBrittany, France
    751.5×
  121. 121BeverenFlanders, Belgium
    751.5×
  122. 122CoyhaiqueAysén, Chile
    751.5×
  123. 123La Roche-sur-YonPays de la Loire, France
    741.4×
  124. 124CharleroiWallonia, Belgium
    741.4×
  125. 125Silao de la VictoriaGuanajuato, Mexico
    741.4×
  126. 126PristinaPristina, Kosovo
    741.4×
  127. 127Haskovolow-cost sensorsHaskovo, Bulgaria
    741.4×
  128. 127MonterreyNuevo León, Mexico
    741.4×
  129. 129AntwerpFlanders, Belgium
    731.4×
  130. 129CouëronPays de la Loire, France
    731.4×
  131. 129ChiguayanteBiobio, Chile
    731.4×
  132. 132Santa CatarinaNuevo León, Mexico
    731.4×
  133. 133AntananarivoAnalamanga, Madagascar
    731.4×
  134. 134Viña del MarValparaiso, Chile
    721.4×
  135. 135AndenneWallonia, Belgium
    721.4×
  136. 135San Pedro de la PazBiobio, Chile
    721.4×
  137. 137AshgabatAshgabat, Turkmenistan
    721.4×
  138. 137ZwijndrechtFlanders, Belgium
    721.4×
  139. 137AricaArica y Parinacota Region, Chile
    721.4×
  140. 140LochristiFlanders, Belgium
    721.3×
  141. 140ToursCentre-Val de Loire, France
    721.3×
  142. 142Ciudad ApodacaNuevo León, Mexico
    711.3×
  143. 143Ulu BedokSingapore
    711.3×
  144. 143TallahasseeFlorida, United States
    711.3×
  145. 145OlivetCentre-Val de Loire, France
    711.3×
  146. 145TalcaMaule Region, Chile
    711.3×
  147. 147Naucalpan de JuárezMéxico, Mexico
    701.3×
  148. 148GraysEngland, United Kingdom
    701.3×
  149. 148Dún LaoghaireLeinster, Ireland
    701.3×
  150. 148Puerto AysénAysén, Chile
    701.3×
  151. 151SalamancaGuanajuato, Mexico
    701.3×
  152. 151CalexicoCalifornia, United States
    701.3×
  153. 153Mexico CityMexico City, Mexico
    691.3×
  154. 154AarschotFlanders, Belgium
    691.2×
  155. 155KapellenFlanders, Belgium
    691.2×
  156. 156IrapuatoGuanajuato, Mexico
    691.2×
  157. 156HueytownAlabama, United States
    691.2×
  158. 158Pachuca de SotoHidalgo, Mexico
    681.2×
  159. 158ConcepciónBiobio, Chile
    681.2×
  160. 158Santiago de QuerétaroQuerétaro, Mexico
    681.2×
  161. 158BrawleyCalifornia, United States
    681.2×
  162. 162SalorTashkent Region, Uzbekistan
    681.2×
  163. 162Los ÁngelesBiobio, Chile
    681.2×
  164. 164StabroekFlanders, Belgium
    681.2×
  165. 165Bishkeklow-cost sensorsBishkek, Kyrgyzstan
    681.2×
  166. 165BexleyEngland, United Kingdom
    681.2×
  167. 165DublinLeinster, Ireland
    681.2×
  168. 168MolFlanders, Belgium
    681.2×
  169. 168LiègeWallonia, Belgium
    681.2×
  170. 170CoulommiersÎle-de-France, France
    671.2×
  171. 170Falconara MarittimaThe Marches, Italy
    671.2×
  172. 172RabinalBaja Verapaz, Guatemala
    671.2×
  173. 172Guatemala CityGuatemala, Guatemala
    671.2×
  174. 174BirminghamAlabama, United States
    671.2×
  175. 175BrusselsBrussels Capital, Belgium
    661.2×
  176. 175Victoria de DurangoDurango, Mexico
    661.2×
  177. 177BanbridgeNorthern Ireland, United Kingdom
    661.2×
  178. 177CalaisHauts-de-France, France
    661.2×
  179. 179Ang Mo Kio New TownSingapore
    661.1×
  180. 179CauquenesMaule Region, Chile
    661.1×
  181. 179AguascalientesAguascalientes, Mexico
    661.1×
  182. 182Abujalow-cost sensorsFCT, Nigeria
    661.1×
  183. 183GaryIndiana, United States
    661.1×
  184. 184TijuanaBaja California, Mexico
    661.1×
  185. 185Queenstown Estatelow-cost sensorsSingapore
    651.1×
  186. 185CalamaAntofagasta, Chile
    651.1×
  187. 187JülichNorth Rhine-Westphalia, Germany
    651.1×
  188. 187AachenNorth Rhine-Westphalia, Germany
    651.1×
  189. 189ReimsGrand Est, France
    651.1×
  190. 189PoitiersNew Aquitaine, France
    651.1×
  191. 191Kuala LumpurKuala Lumpur, Malaysia
    651.1×
  192. 191LotaBiobio, Chile
    651.1×
  193. 193León de los AldamaGuanajuato, Mexico
    651.1×
  194. 193GuanajuatoGuanajuato, Mexico
    651.1×
  195. 195Addis AbabaAddis Ababa, Ethiopia
    641.1×
  196. 195BastiaCorsica, France
    641.1×
  197. 195Little RockArkansas, United States
    641.1×
  198. 198Las Palmas de Gran CanariaCanary Islands, Spain
    641.1×
  199. 198LondonEngland, United Kingdom
    641.1×
  200. 198ChâteaurouxCentre-Val de Loire, France
    641.1×

Top 200 of 1,227 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, April 18, 2023, smogrank.com/history/2023-04-18 (accessed 2 Oct 2026).

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