Delhi sees lower air pollution levels this October

Levels of major air pollutants in the capital during October this year have remained lower than in most previous years, with a private Delhi-based think tank’s dashboard showing declining concentrations of particulate matter, nitrogen dioxide and ozone.

The public-access dashboard, tabulating Central Pollution Control Board (CPCB) and Commission for Air Quality Management (CAQM) data on various air pollution parameters, has been prepared by Envirocatalysts.

The data, based on averages recorded till October 25 this year against full-month averages for 2015-2025, showed that the average PM2.5 concentration stood at 67 micrograms per cubic metre (µg/m³) in October 2026, compared with 108 µg/m³ in October last year and 147 µg/m³ in 2016 — the highest during the period under observation.

The data showed that average PM2.5 concentration in Delhi stood at 111 µg/m³ in 2024, 103 µg/m³ in 2023, 105 µg/m³ in 2022, 75 µg/m³ in 2021, 133 µg/m³ in 2020, 123 µg/m³ in 2019, 134 µg/m³ in 2018, 115 µg/m³ in 2017, and 121 µg/m³ in 2015 — all of which are higher than this year’s reading.

PM10 levels also declined this year, with the average concentration at 172 µg/m³, compared with 217 µg/m³ in 2025 and 345 µg/m³ in 2016.

Nitrogen dioxide (NO2) levels averaged 36 µg/m³ from October to date, lower than 48 µg/m³ in 2025 and 79 µg/m³ in 2016, according to the data. Ozone concentrations stood at 55 µg/m³, compared with 78 µg/m³ last year and 101 µg/m³ in 2015. However, the October average was marginally higher than the 54 µg/m³ recorded in 2023 and 2021.

Carbon monoxide (CO) levels averaged 1.80 milligrams per cubic metre (mg/m³), the same as in 2025 and lower than 2.10 mg/m³ in 2024 and 4.70 mg/m³ in 2016.

The data showed that concentrations of all five pollutants till October 25 this year were lower than their October averages in 2020, when PM2.5 stood at 133 µg/m³, PM10 at 284 µg/m³, NO2 at 59 µg/m³, ozone at 81 µg/m³ and CO at 2.30 mg/m³.

The figures compare pollution levels in October, although meteorological conditions, including wind speed, temperature, humidity, and rainfall, also influence pollutant concentrations and their dispersion.