Samut Sakhon’s Mueang district ranked most polluted city in Thailand

Samut Sakhon’s Mueang district topped the most polluted cities in Thailand on Tuesday, according to the IQAir website.

The air quality index (AQI) in Samut Sakhon was measured as unsafe for everyone at 177 as of 9am, which is higher than the safe standard of 51-100 AQI.

AQI was measured from six air pollutants, including PM2.5, PM10, ozone (O3), carbon monoxide (CO), nitrogen oxide (NO2) and sulfur dioxide (SO2).

The nine most polluted cities following Samut Sakhon included: 


Rayong’s Pluak Daeng district (173)
Nakhon Pathom’s Mueang district (165)
Samut Songkhram’s Mueang district (163)
Sa Kaeo’s Aranyaprathet district (163)
Samut Prakan’s Phra Pradaeng district (148)
Rayong’s Mueang district (144)
Saraburi’s Mueang district (134)
Chiang Mai’s Hang Dong district (133)
Phetchabun’s Mueang district (132)


Bangkok was ranked 11th with AQI measured as unsafe for vulnerable people at 131.

However, the Bangkok Air Quality Information Centre reported the PM2.5 situation in the capital with an average concentration of 28.1 micrograms per cubic metre (mcg) as of 7am.

Only two districts where the air quality reached unsafe levels: Lat Krabang (39.6 mcg) and Nong Chok (39.0 mcg)



PM2.5 refers to fine particulate matter with a diameter of 2.5 micrometres or less, which can penetrate deep into the lungs and bloodstream, posing health risks such as respiratory and cardiovascular diseases.

Major sources of PM2.5 include traffic emissions, factories, forest fires and burning of harvest leftovers.

(2025/02/11-00:00)