India 6th most polluted country in the world: World Air Quality Report

India’s particulate matter (PM2.5) concentrations were at a three-year low, although it remains the sixth most polluted country in the world, according to the World Air Quality Report, an annual compilation of global air quality by IQAir, a Swiss company that manufactures air filtration devices.

India’s population-weighted annual average PM2.5 concentration in 2025 is 48.9 µg/m³, a decrease of 3% compared to 2024 (50.6 µg/m³) and 10% compared to 2023 (54.4 µg/m³). The 2025 figures were part of a report that is now in its eighth edition and was made public on Tuesday, March 24, 2026.

The population-weighted figures IQAir calculates give greater weight to particulate matter counts in cities with higher populations; This is a measurement intended to highlight the air quality to which the majority of a country’s population is exposed.

In 2023, India ranked 3rd globally after Bangladesh and Pakistan. In 2024, it fell to 5th place as Chad and the Democratic Republic of Congo entered the rankings with higher concentrations. While India ranked 6th in the 2025 report, it is now behind Tajikistan. In the 2025 edition, more countries with high pollution loads that were not monitored until now entered the IQAir compilation. In 2025, there were 143 countries (covering 9,446 cities), while in 2023 there were 134 countries (covering 7,812 cities).

New Delhi’s annual PM2.5 concentration increased from 92.7 µg/m³ in 2023 to 108.3 µg/m³ in 2024 (up 6%, its highest level since 2019) and then decreased to 82.2 µg/m³ in 2025; This is the lowest level in three years and is down 8% from the previous year. Yet New Delhi remains the world’s most polluted capital.

In 2023, Begusarai in Bihar was the most polluted metropolitan area in India and the world. In 2024, it was Byrnihat on the Assam-Meghalaya border (128.2 µg/m³). In 2025, Loni achieved pole position in Ghaziabad district of Uttar Pradesh with 112.5 µg/m³. “Only PM10 concentrations were targeted instead of the more harmful PM2.5. Weak enforcement of vehicular and industrial emission norms, coupled with relaxed sulfur rules for coal power plants, likely affected air quality,” a section of the report on India said. The report relies on publicly disclosed data from countries’ monitoring networks for its analysis. These are highly variable and poorer cities and countries have fewer monitors per unit of population and often fail to give a representative picture of their air quality.

The 2025 report notes that India’s National Clean Air Program has directed 64 percent of its funding towards reducing road dust, which mainly consists of watering and sweeping roads, with only 15 percent going to biomass burning, 13 percent to vehicle emissions, and only 1 percent to industrial pollution. It also noted public protests at India Gate in New Delhi in November 2025 following increases in air pollution.

In 2024, 74 of the 100 most polluted cities worldwide were in India; this figure was a slight improvement from 83 in 2023. The 2025 report states that 17 of the world’s 20 most polluted cities are in the Central and South Asia region, with the “majority” in India and Pakistan.

Only thirteen countries/territories worldwide met the WHO annual average PM2.5 guideline: French Polynesia, Puerto Rico, US Virgin Islands, Barbados, New Caledonia, Iceland, Bermuda, Réunion, Andorra, Australia, Grenada, Panama and Estonia.