SHILLONG, March 12: Byrnihat, an industrial town on the Assam-Meghalaya border, has been identified as the world’s most polluted city in 2024, according to the World Air Quality Report 2024 published by Swiss air quality technology firm IQAir. The report, released on Tuesday, also highlighted India’s improvement, as it ranked as the fifth most polluted country in the world, down from its third position in 2023.
Byrnihat recorded an annual average PM2.5 concentration of 128.2 µg/m3, surpassing New Delhi, which has long held the title of the world’s most polluted capital. The town, located near Guwahati, is home to numerous small-scale industrial units producing ferroalloys, tyres, cement, and polythene, all of which significantly contribute to hazardous levels of air pollution. Additionally, the heavy movement of interstate trucks exacerbates the already deteriorating air quality in the area.
India continues to be a major contributor to global air pollution, with six of its cities among the ten most polluted worldwide. Despite this, Gangtok was identified as one of India’s least polluted cities, with an AQI of just 13. Meanwhile, New Delhi remains the most polluted capital in the world.
The Central Pollution Control Board (CPCB) and the Meghalaya State Pollution Control Board (MSPCB) have repeatedly flagged Byrnihat’s deteriorating air quality. The MSPCB issued closure notices to several ferroalloy manufacturing units last year for failing to meet environmental norms.
IQAir’s analysis, which included data from over 40,000 air quality monitoring stations across 8,954 locations in 138 countries, also pointed out that only seven countries—Australia, Bahamas, Barbados, Estonia, Grenada, Iceland, and New Zealand—currently meet the World Health Organization’s (WHO) annual PM2.5 guideline of 5 µg/m3.
In terms of global pollution, 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). Meanwhile, Honokaʻa in Hawaii recorded the world’s lowest AQI at just 1.
