IQAir World Air Quality Report 2025
Context:
The Swiss air quality technology company IQAir recently released its World Air Quality Report 2025.
The report highlights a worsening global air quality scenario, noting that despite policy efforts and funding, severe pollution hotspots persist, particularly in Central and South Asia
Global Findings:
WHO Compliance Deficit:
Approximately 91% of countries (130 out of 143) recorded PM2.5 levels exceeding the World Health Organization's (WHO) safe annual guideline of 5 µg/m³.
Only 14% of global cities met the standard in 2025, a decline from 17% in 2024.
Most Polluted Nations:
Pakistan ranked as the world's most polluted country in 2025 (with a PM2.5 concentration of 67.3 µg/m³).
It was followed by Bangladesh, Tajikistan, Chad, and the Democratic Republic of the Congo.
India's Position and Regional Hotspots:
National Ranking:
India continues to face a severe air quality crisis, ranking as the sixth most polluted country globally.
Its national average PM2.5 concentration stood at 48.9 µg/m³, which is nearly 10 times higher than the WHO limit.
The Most Polluted City:
India is home to the most polluted city in the world.
Loni (in Ghaziabad, Uttar Pradesh) topped the global list with an annual average PM2.5 concentration of 112.5 µg/m³ (more than 22 times the WHO limit).
Byrnihat (Meghalaya) ranked third globally.
Most Polluted Capital:
New Delhi continues to be the world’s most polluted capital city for the eighth time, ranking fourth overall among all global cities.
The NCR Hotspot:
The report flags the National Capital Region (NCR) as a severe regional pollution hotspot.
The toxic air here is driven by shared, overlapping sources like industrial smog, vehicular emissions, construction dust, and stagnant winter air.
Key Concept:
PM2.5:
Fine particulate matter with a diameter of 2.5 micrometres or less.
Due to its microscopic size, it can easily penetrate deep into the human respiratory system and enter the bloodstream, causing severe cardiovascular and respiratory issues.