Hold your breath: Transport sector is now the biggest source of Mumbai’s air pollution

Tiny, deadly particles in Mumbai’s air from the transport sector have nearly doubled over the past five years, making it now the biggest contributor to the city’s already deteriorating air quality.

A 2019-20 source estimation analysis for PM2.5 pollutant by the System of Air Quality Weather Forecasting And Research (SAFAR), under the Indian Institute of Tropical Meteorology (IITM) Pune, has revealed that the share of PM2.5 emissions coming from the transport sector was 30.5% in 2019-20 as compared to 16% in 2016-17.

Air has suspended particulate matter (PM) of different sizes. Many of these are a complex mixture of dust, pollen, soot, and smoke, and they are hazardous. Of this, PM 2.5 is the smaller kind, with a diameter, not more than 2.5 micrometers (fine particles). PM2.5 is considered to have a very significant health impact as it can stay in the air for days or weeks, and is small enough to invade the lung airways.

Read | People residing in highly polluted areas of Maharashtra prone to Covid-19 infection: Study

As per SAFAR, the contribution to PM2.5 emission from different sectors, between 2019-20, was 30.5% from the transport sector, 18% from industries and power sector, 15% from residential burnings, which includes residential cooking in households and slums, trash burning, cow dung burning, emission from street vendors, and wood burning.

The remaining sources polluting Mumbai’s air with more PM2.5 particles include wind-blown dust (15%) and other sources (21.5%) including municipal solid waste (MSW) plants, MSW open burning, crematories, aviation sector, incense, brick kilns, etc.

Read | Climate Change: Scientific approaches required

Dr Gufran Beig, Senior Scientist and Founder Project Director, System of SAFAR, said, “Transport sector has shown a drastic increase over five years as a sector contributing to PM2.5 pollution in Mumbai. This is a combination of both an increase in the number of vehicles in Mumbai and more stagnation at traffic junctions leading to congestion.”

Pulmonologist Dr Sanjeev Mehta, said, “Vehicles are literally blowing poison into our lungs. Emissions from the transport sector, especially diesel and petrol vehicles, have a noxious mixture of suspended particles of all sizes that causes damage to the upper, middle and lower airways or nose, throat and lungs.”