Mumbai's high AQI explained: Why the air got suddenly worse and what needs to be done?

Mumbai AQI (Credit: X)

Mumbai’s air quality has hit hazardous levels recently. As per the Sameer App, the AQI during the late hours of Wednesday went all the way up to 198, with two suburbs, Malad West with an AQI of 308 and Borivali East at 303, both breaching the 300 mark. However, the AQI readings on Thursday morning stood at 182.

Key pollutants such as PM2.5 and PM10, which are tiny particulate matters harmful to lungs and heart, have surged drastically. PM2.5 levels are around 176, and PM10 over 150 at many monitoring stations, pushing AQI into the “hazardous” range.

What's behind Mumbai air crisis?

Mumbai’s worsening air quality is the result of a layered mix of local pollution sources and seasonal weather shifts that have collectively pushed the city into an alarming zone.

According to the environmental experts, both human-made emissions and natural atmospheric conditions are working together to trap pollutants over the metropolis.

Mumbai air pollution: Construction dust adds to woes

A major contributor is the surge in construction across Mumbai, which has been continuously sending dust and coarse particles into the air.

Mumbai toxic air: Road dust and vehicular emissions

The roadwork activity after end of the rainy season has increased road dust across the city. These emissions are further compounded by the city’s ever-growing vehicular load and the frequent use of diesel generators, particularly in industrial hubs like Mahul.

Industrial fumes in eastern Mumbai

Heavy industries and refineries along the eastern corridor add to the toxic mix by releasing industrial fumes round the clock. Also, open burning also majorly contributes to air pollution in Mumbai, especially in the areas with maximum slum settlements. Last winter, maximum violators for open burning were found in Deonar.

Mumbai's high power demand and diesel generators 

Another emerging factor is the soaring electricity demand from Mumbai’s rapidly expanding data centre ecosystem. To meet this rising need, fossil-fuel power plants and large diesel generators have been operating for longer hours, which significantly worsens the city’s pollution burden.

La Nina and other meteorological factors

Mumbai typically benefits from a regular sea breeze off the Arabian Sea that helps flush out pollutants. However, this natural ventilation has been notably absent due to an early onset of La Niña, which alters usual wind patterns and suppresses the sea breeze.

Along with warm atmospheric conditions and high humidity, this results in a ‘lid’ effect that traps polluted air near the surface. The cessation of the monsoon rains has also stopped the natural wet cleaning of the atmosphere, allowing pollutants to accumulate over time without dispersal or washout.

These combined pressures are leading to rising cases of respiratory irritation in the city. Children, senior citizens, and individuals with pre-existing conditions are particularly vulnerable to the health impact of prolonged exposure.

What needs to be done to combat high Mumbai AQI?

The spike in pollutants results increased hospitalisation for asthma and cardiac diseases. Experts urge urgent curbs on construction activities, promotion of clean energy alternatives, and strict pollution control in industrial and traffic-heavy areas to mitigate this crisis.

Mumbai has already launched an emergency anti-pollution offensive, authorising a complete halt to construction work and other polluting activities if the city’s air quality continues to deteriorate.

Also, to discourage people from open garbage burning and lighting warming fires, the BMC's enviornment department is planning to increase the penalty against open burning to Rs 5000.

According to reports, last year, the fine for open burning was only Rs 100, which is increased to Rs 500 this year. Officials believe if this amount is increased further, the violators will start taking the matter seriously.