Kolkata, twin city Howrah breathe murky air on both sides of the Hooghly

Giving the lie to much touting of ‘clean air despite crackers’ on social media by assorted citizens (some of whom might be suspected of sharing doctored screenshots from near an air purifier, or passing off old ones as current), West Bengal’s biggest twin cities on either side of the Hooghly-Ganga — Kolkata and Howrah — woke up to ‘poor’ air quality on 22 October, Wednesday.

West Bengal capital Kolkata saw AQI values ranging from 128 to 242 (PM2.5) across monitoring stations this morning. Specifically, readings included 200 at Jadavpur, 141 at Ballygunge, 142 at Rabindra Bharati University (Sinthi), 165 at New Town and 150 at Fort William, while the Victoria Memorial station touched a notable high of 242. Most areas hovered in the ‘poor‘ (151–200) range, some edging into ‘very poor’ and a few moments the previous day saw spikes into ‘severe’ (over 300). On the other side of the river, Howrah echoed Kolkata, with Belur at 213 and Ghusuri at 179.​

Environmentalists blamed Diwali and Kali Puja celebrations, noting persistent particulate matter after widespread fireworks, with some areas reporting illegal high-decibel firecracker use into the midnight hours.

Residents reported lingering smog and discomfort for pets, children and elderly citizens.

“Pollutants hung in the air till Wednesday noon after the frenzied celebrations, with pets and newborns shaken by loud sounds. High-decibel firecrackers were burst everywhere in the city,” said Somendra Mohan Ghosh.

Naba Dutta of the citizens’ environmental advocacy group Sabuj Manch claimed that “monitoring teams found fireworks bursting in silence zone areas like R.G. Kar Hospital surroundings throughout the Kali Puja–Diwali nights”.

Both environmentalists attributed the consequences to lax enforcement by police and pollution authorities.

Officials from the West Bengal Pollution Control Board acknowledged the elevated AQI, but claimed, “Worsening of AQI cannot be directly linked to bursting of firecrackers, which was less than last year. Also, green fireworks ratified by NEERI were used mostly.”

They cited stagnant weather — hot, humid and windless — as a key factor, adding, “Any worsening of AQI can be attributed to the weather, with pollutants hanging in the air amid hot and humid conditions in the absence of rain or southerly winds…”

But Delhi is still far (ahead)...

Along the same lines as the WBPCB — and opposing the cohort claiming very clean air after extensive application of ‘green crackers’ — were those of our netizens who took, among others, Trinamool Congress MP Sagarika Ghose to task for complaining about capital city Delhi’s venomous air quality when things ‘back home’ were equally dire.

But then, that required some quality cherry-picking. For Kolkata’s moderate-to-bad areas equated to Delhi’s ‘cleaner’ zones (such as Panchsheel, cited by one user on X).

For overall, Delhi has grappled with even worse air quality post-Diwali, with no signs of relief until Chhath Puja (27 October) is done and dusted.

The capital’s AQI soared as high as 447 at peak hours, placing it solidly in the ‘severe’ category — making it the most polluted metro in India this week. Most Delhi monitoring stations registered 275–350, with ‘very poor’ and ‘severe’ health warnings throughout the city. On Wednesday, PM2.5 concentrations in New Delhi exceeded World Health Organization guidelines by over 40 times, with smog visibly blanketing the city.

Yet while this is bad enough, it is a supposed ‘vast improvement’ on the immediate post-Diwali numbers, where some places in the NCR crossed ‘999’ on personal air quality monitors and several officially recognised monitoring stations approached 1,000 (the meters can’t register a reading beyond 999, however, since they use 3-digit displays).

While Kolkata and Howrah’s AQI primarily reflected post-firework conditions and meteorological stagnation, Delhi’s crisis is aggravated by stubble burning in nearby agricultural districts, recurring winter inversion and routine breaches of firecracker bans.

Health experts have recommended limiting outdoor activities, noting that breathing air in Delhi during peak pollution is akin to smoking 8.5 cigarettes a day.

Southern metros such as Chennai, Bengaluru and Hyderabad, in contrast, reported AQIs under 100 (‘satisfactory’ range).​

Summary of AQI readings 21–22 October 2025

City AQI PM2.5 Air quality Main contributors

Kolkata 128–242 ~50–190 poor–very poor fireworks, stagnant weather

Howrah 179–213 ~60–180 poor–very poor fireworks, industrial, weather

Delhi 275–447 194 (avg) v. poor–severe stubble burning, firecrackers,

weather inversion

Chennai 52 30 (avg) satisfactory low emissions, better

weather

Bengaluru 64 27 (avg) satisfactory low emissions, favourable

winds

Despite regional and seasonal improvements being attributed to green fireworks and stricter controls (even Delhi was worse last year), both Kolkata and Delhi face persistent air pollution spikes around major festivals, however — with their challenges compounded by meteorological conditions and incomplete enforcement of public health measures.

But in terms of damage done, they are almost orders of magnitude apart.