The 'World Air Quality Report, 2020', prepared by Swiss organisation IQAir, shows Bangladesh, China, India, and Pakistan account for 49 of the 50 of the most polluted cities worldwide.

 

In country rankings, Bangladesh has the worst air, followed by Pakistan and India. In the world capital city ranking, Delhi fares the worst, followed by Dhaka and Ulaanbaatar.

 

Notably, India showed an overall improvement in several cities, with 63 per cent reporting direct improvements over 2019 averages, the report stated.

 

It added that the progress is only marginally attributable to India's flagship National Clean Air Programme (NCAP) introduced in January 2019, which targets PM2.5 reductions between 20-30 per cent in 122 selected cities by 2024 from a 2017 baseline.

 

According to the report, despite widespread air quality improvements during 2019 and 2020, air pollution in India is still dangerously high.

 

India continues to dominate annual PM2.5 rankings by city - 22 of the top 30 most polluted cities globally are located in India.

 

Major sources of India's air pollution include transportation, biomass burning for cooking, electricity generation, industry, construction, waste burning, and episodic agricultural burning.

 

Transportation constitutes one of India's leading PM2.5 emission sources, responsible for emitting pollutants and re-suspending road dust.

 

Biomass cookstoves are the main source of indoor pollution nationally, particularly affecting women and children, the report stated.

 

"Delhi, the world's second most populous city, is located southeast of India's agricultural breadbasket, where open burning is common," it added.

 

It is estimated that as much as 20 to 40 per cent of Delhi's air pollution originates from Punjab farm fires During peak burning season, Delhi experienced average PM2.5 levels in November and in December, which exceed the WHO's annual exposure guideline by more than 14 times.