Shillong, Mar 12: Byrnihat, an industrial town on the Assam-Meghalaya border, has been identified as the world’s most polluted city in 2024, surpassing New Delhi, according to the World Air Quality Report 2024 published by Swiss firm IQAir. The report, released on Tuesday, also ranked India as the fifth most polluted country, improving from its third position in 2023.

Byrnihat recorded an annual average PM2.5 concentration of 128.2 µg/m3, making it the most polluted metropolitan area globally. The town, located near Guwahati, is home to numerous small-scale industrial units producing ferroalloys, tyres, cement, and polythene, which significantly contribute to hazardous air pollution levels. Additionally, heavy interstate truck movement further worsens air quality.

India continues to be a major contributor to global pollution, with six of its cities among the ten most polluted worldwide. While New Delhi remains the world’s most polluted capital, Gangtok recorded an AQI of 13, making it one of India’s least polluted cities.

The Central Pollution Control Board (CPCB) has repeatedly flagged Byrnihat’s deteriorating air quality, while the Meghalaya State Pollution Control Board (MSPCB) last year issued closure notices to several ferroalloy manufacturing units for failing to comply with environmental norms.

IQAir’s analysis examined data from over 40,000 air quality monitoring stations across 8,954 locations in 138 countries. The report highlighted that only seven countries—Australia, Bahamas, Barbados, Estonia, Grenada, Iceland, and New Zealand—meet the World Health Organization’s (WHO) annual PM2.5 guideline of 5 µg/m3.

The five most polluted countries in 2024 were Chad (91.8 µg/m3), Bangladesh (78.0 µg/m3), Pakistan (73.7 µg/m3), the Democratic Republic of the Congo (58.2 µg/m3), and India (50.6 µg/m3). Honokaʻa in Hawaii recorded the world’s lowest AQI at just 1.