IQAir data shows that South Tangerang had the worst air quality among ASEAN cities in 2024.
Its average air quality was 61.1 micrograms per cubic meter (µg/m³), far exceeding the World Health Organization (WHO) safe limit of under 5 µg/m³ for PM2.5 concentration.
Besides South Tangerang, several other Indonesian cities also ranked among the top 10 worst polluted cities.
These include Tangerang at 55.6 µg/m³ (second place), and Cikarang at 52.8 µg/m³ (third place).
Thanh Pho Phu Ly, Vietnam, ranked fourth with an average air quality of 50.9 µg/m³, followed by Depok in fifth place at 50.3 µg/m³.
The remaining cities in the top ten were Hanoi, Tay Ho, Banting, Luong Son, and Bekasi, as shown in the graph.
(Read also: Only 12 Areas Met WHO Air Quality Standards in 2024)
Indonesia's Condition
IQAir stated that the average PM2.5 concentration in Indonesia in 2024 decreased by 4% compared to 2023, reaching 35.5 µg/m³. This value is ten times higher than the WHO guideline.
"Despite a slight improvement, Indonesia remains the most polluted country in Southeast Asia and ranks 15th among the world's most polluted countries," wrote the Swiss air quality monitoring company, as quoted on Thursday (March 13, 2025).
In Jakarta, IQAir added, PM2.5 levels dropped by almost 5% from 2023, with an annual average of 41.7 µg/m³.
IQAir assessed that the abatement of El Niño, a dry climate pattern that intensified forest fires in 2023, likely contributed to a 60% decrease in hotspots in Indonesia in 2024, leading to a reduction in emissions from biomass burning.
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