The air quality in Kolkata was worse than that in Delhi in the past one week, with an unprecedented spike in AQI between 6 and 12 December.
Source: AQI.in
For seven consecutive days, city residents choked under toxic smog as AQI stayed higher than that in the national capital, reaching the ‘severe’ — and sometimes ‘hazardous’ — category.
The numbers are alarming and speak for themselves. Between 6 December and 12 December, according to AQI.in, Kolkata’s AQI fluctuated between 184 and a staggering 439. The peak came on 11 December at 6.04 pm, placing the city firmly in the severe danger zone.
Source: AQI.in
Delhi, despite its long-standing reputation for toxic winter smog, recorded a lower AQI — between 172 on 10 December and 345 on 11 December. In the last 24 hours alone, Kolkata hit an even more shocking 558 AQI at 11.04 pm on 11 December, higher than Delhi’s worst reading of 477 recorded at 4.04 am on 12 December.
The West Bengal Pollution Control Board is yet to issue an official statement regarding the worsening air quality in Kolkata. Representatives of the pollution watchdog did not respond to calls from My Kolkata on Friday.
A previous analysis by My Kolkata in late November showed Kolkata’s air steadily deteriorating even as Delhi battled its annual smog. Now, the concern has escalated into an alert.
Understanding the numbers is key to understanding the danger. AQI between 51 and 100 is generally safe, though mildly discomforting to sensitive groups. Between 101 and 200, people with respiratory issues may find it difficult to breathe. The 201 to 300 range, categorised as poor, is when the irritation becomes widespread. Throat itching, burning eyes and breathlessness become common. The very poor category between 301 and 400 is linked to reduced lung capacity, inflamed airways and frequent asthma attacks. Anything above 400 is severe, harmful to everyone, and can trigger chest tightness, coughing fits and severe complications for those with heart disease or chronic lung conditions.
Source: AQI.in
According to the cigarette-equivalent exposure metric, simply breathing the city’s air in the last 24 hours is as harmful as smoking 11.2 cigarettes a day. That adds up to more than 78 cigarettes a week and over 330 a month.
Doctors say the danger goes far beyond the immediate symptoms. The real damage builds over time. Arup Halder, pulmonologist at CMRI Kolkata, said, “Air pollution is not just a public health issue, it is a threat that begins harming a child even before they take their first breath. The latest evidence shows that chronic exposure to particulate pollution in pregnant women increases the risk of babies being born too small or too early. These newborns are far more vulnerable and face lifelong health risks.”
With Kolkata’s AQI shooting past 500 in parts of the city, the situation has become serious enough for doctors to advise reduced outdoor exposure, especially for children, pregnant women, the elderly, and those with existing respiratory or cardiac conditions. Masks and air purifiers, once seen as precautionary tools, are increasingly becoming essential winter gear.
As winter sets in and wind speeds drop, experts warn that the pollutants trapped close to the ground may not disperse quickly. This means Kolkata may continue to gasp for breath unless conditions change sharply. For now, the city finds itself in a worrying and unfamiliar position as it grapples with rising air pollution.