There’s something in the Mumbai air
Shabnam Abdul Gaffar Shah, 35, is wheezing. The air around her in the slums of Mumbai’s Mankhurd, a few hundred metres from an under-construction metro project, smells of soot and dust. “Everyone in the house – my three children, husband, and I – has been ill for the past month. We went to the doctor. He said, ‘Hawa kharab hai(The air is bad).’ The cough and cold wouldn’t go,” she says, sitting just outside her single-room home on a road down which rush schoolchildren, honking two-wheelers, BEST buses trying to navigate dug-up peripheries, and streetside vendors jostling for space in the same chaos. Medical expenses have become a challenge, she says. “Kitni dawa-daru karenge? (How much will we spend on medicines?)”
Around 15 km away, in Matunga, an area dotted with several top ranking colleges, including Podar and Ruia, professors of Khalsa College are worried about their students who commute by public transport and walk down dusty roads to reach the campus. The construction of high-rise structures to replace old four-storeyed ones is in full swing in the area.
A study by the Maharashtra Pollution Control Board (MPCB) in 2023 to find out the sources of air pollution in 10 cities in the State showed that dust contributed to 30% of PM10 pollution in Mumbai. PM is a reference to particulate matter, which can be inhaled, defined by its diameter: 10 micrometres and 2.5 micrometres, for instance. These can enter the lungs and have an adverse effect on health, both immediate and in the long-term, if exposure is constant.
Mumbai’s air quality over the past three years has frequently ranged from ‘moderate’ to ‘severe’, with PM2.5 and PM10 levels often exceeding safe limits, driven up by vehicular emissions, dust, and winter conditions that lead to stagnation of air.
Thick blanket of smog over the city skyline as seen from Bandra on December 5, 2025.
| Photo Credit:
Emmanual Yogini
Respirer Living Sciences, a climate tech start-up, released a report this year that stated that Mumbai saw a 2.6% increase in PM2.5 levels from 35.2 g/m³ in 2019 to 36.1 g/m³ in 2024, reflecting a persisting air quality issue for India’s financial capital. It added that Mumbai witnessed remarkable improvement in the number of ‘good’ days, increasing from 164 in 2021 to 184 in 2024. However, the persistence of ‘moderate’ and ‘poor’ days in 2022 and 2023 highlighted the presence of localised pollution sources, particularly during construction-heavy periods, it stated.
Barely 3 km away, advocate Shweta Mehta stays in a neighbourhood touted to be the next big connectivity hub of coastal Mumbai: Wadala. Located less than 2 km from the upcoming New Cuffe Parade area, where metro, monorail, and key infrastructure projects are coming up, the dust in the area is thick.
Mehta, who lives in an apartment block, says, “Due to poor air quality over the past few months, I have been restricting my parents from stepping out. They have lung-related ailments and I have asked them to stay indoors.” She is aware that her ageing parents are beginning to feel frustrated and lonely, with their social life disrupted, but for Mehta, it’s a difficult choice.
Doctors and lawyers speak out
Dr. Asmita Mahajan, consultant and head of the Department of Paediatrics and Neonatology at Mahim’s Fortis Raheja Hospital, feels there should be a pollution lockdown in the city. “When did you last see clear skies?” she says.
Until a few years ago, she would see a seasonal spike in the number of children coming to the hospital with allergic respiratory conditions. “Allergic coughs take months to go away. Children with asthma see an exacerbation of symptoms.”
Until last year, Mahajan says, she used to see two children per week with respiratory problems. It has now gone up to six per week. “There are repeat hospital admissions, especially of children with asthma. Some need hospitalisation and ICU admission too,” she says.
Dr. Samir Garde, a pulmonologist in Mumbai, says 25 years ago, the leading cause of lung cancer was smoking. Now, many non-smokers contract serious lung diseases, including cancer.
He attributes one of the reasons to air pollution. He hopes the government will prioritise public health.
Looking at the persistent air quality problem, the Bombay High Court tooksuo motucognisance of the matter in 2023. It initiated a public interest litigation plea to address deteriorating air quality levels and rising pollution from construction dust. In October 2023, the court issued detailed orders, including 28 guidelines to be implemented by the Brihanmumbai Municipal Corporation (BMC) at construction sites. These included mandatory installation of air quality sensors and water sprinklers, and placing covers on vehicles transporting construction material.
On November 27 this year, the court flagged the sharp decline in the air quality index (AQI) (up to 270, classified as ‘poor’) and rejected the ‘volcanic ash from Ethiopia’ theory.
Amicus curiaeand senior advocate Darius Khambata highlighted the worsening of air quality since 2023 and non-compliance at construction sites. Of nearly 1,000 construction sites in the city, only 400 have installed sensors mandated by the court’s earlier order, and 117 of those are non-functional. Moreover, these sensors are yet to be linked to a central monitoring system, he pointed out.
The court stressed that Mumbai needed a sustained plan to combat rising pollution and ordered the formation of a committee to ensure strict compliance with existing guidelines for construction sites. It also noted that earlier committees had failed to submit weekly compliance reports since March 2025.
The new committee is expected to submit its findings within a week, after which the matter will be heard again on December 15.
Data points
This month, BMC Commissioner Bhushan Gagrani announced Project MANAS, in collaboration with IIT Kanpur, to instal a hyperlocal sensor-based ambient air quality monitoring system.
“What will you do even when monitors are installed? Do we not have enough air quality data already?” says Rakesh Kumar, president of the non-profit Society for Indoor Environment, and former director of the Council of Scientific & Industrial Research’s National Environmental Engineering Research Institute (CSIR-NEERI). He says the real problem is not the unavailability of data for measuring ambient air quality, but translating that data into action.
He also points out that the data is generic. “Let’s talk about the transportation sector. You have a mix of vehicles of different vintages. Of the 100 vehicles that are on the road, 50-60 are regularly on the road. Some are there for construction activities: vehicles carrying material and debris. They go to different construction sites. That is the data we need,” he says.
He adds that it is necessary to go into granular data on road movement. Banning all construction activities suddenly and implementing curbs under Stages III and IV of the Graded Response Action Plan overnight are knee-jerk reactions, he feels. “We are missing some piece of information. That will not come from ambient air quality measurement,” he says.
Tuhin Banerji, former scientist at CSIR-NEERI and current coordinator of the non-profit International Center for Climate and Sustainability Action, feels the government knows the solutions but isn’t willing to invest in them. “Everyone is only talking about monitoring. Nobody is doing anything about removing these pollutants. There are molecular filters that can selectively remove pollutants from the atmosphere,” he says.
He gives a list of interventions like electrostatic precipitators to remove particulate matter; WAYU (wind augmentation purifying unit), an outdoor air purifying device developed by the CSIR-NEERI to combat air pollution in high-traffic zones; and Techno Green Yuka Yantra, a patented solution for air quality. He, too, laments “the lack of bureaucratic will” to implement them.
People walk at Girgaon Chowpatty as city skyline is seen engulfed in smog on December 5, 2025.
| Photo Credit:
Emmanual Yogini
Environmentalists have accused authorities of obfuscating crucial data on air quality. Sumaira Abdulali has been tracking air quality for years. As part of her awareness campaign, she used to put out PM2.5 level data every day for over a year. Then, suddenly, in May this year, PM2.5 data was not available on the Central Pollution Control Board’s (CPCB) Sameer app, which gives real-time updates on AQI and other parameters.
“Till May 2025, all the readings were in red. In fact, in April this year, the PM2.5 level in Kandivali [a Mumbai suburb] was 434, way above the red zone,” she says. Abdulali raised the issue of data unavailability with authorities, asked questions for a while, but says she got no answers.
“We know that PM2.5 is more dangerous. The structure of your nose can stop PM10. But PM2.5 particles go into your lungs. They can cause all sorts of problems: coughing, wheezing. Long-term exposure can cause cancer,” Banerji says.
Asked why PM2.5 data was no longer available on the Sameer app, MPCB officials say the data was controlled by the CPCB. “You will have to ask them,” says MPCB Joint Director (Air) Satish Padwal. “There has to be one monitoring centre per 10 lakh population. There are excess stations in Mumbai at present,” he adds. The Sameer app shows that 23 of the 30 stations were active.
Gagrani admits that air quality is a critical public health and governance priority.
“Stop-work notices have been issued to 321 sites. We are carrying out road watering, mist spraying, site-wise visits, and urging bakeries to switch to clean fuel,” he says.
However, experts say mist spraying does not work to curb air pollution. The BMC has deployed 94 flying squads to ensure strict adherence to the 28 guidelines formulated for construction sites. Show-cause notices were issued to the bullet train project and Dharavi redevelopment project, says Ashwini Joshi, Additional Municipal Commissioner of BMC.
vinaya.deshpande@thehindu.co.in
