Mint Explainer | Why Delhi's recurring air pollution crisis is a health concern

Delhi's recurring pollution crisis is sending more people to hospitals, with exposure to toxic air posing risks that extend beyond respiratory illness. Why seasonal curbs offer only temporary relief, and what it will take to break the cycle.

Every year, as temperatures fall, Delhi's air turns hazardous and hospitals see a surge in patients struggling to breathe. Schools close and emergency curbs kick in, but the respite is temporary. Then the cycle begins again.

The health toll, meanwhile, is mounting. Fine particulate matter, particularly PM2.5, penetrates deep into the lungs and can enter the bloodstream, putting even healthy people at risk of harm beyond the respiratory system.

The concern is what repeated exposure to toxic air is doing to a generation growing up in Delhi. Mint explains.

Pulmonologists across the National Capital Region (NCR) have reported a surge in hospital visits as air quality worsens. Outpatient departments (OPDs) are treating persistent dry coughs, sinus pain, throat irritation, nasal discharge and burning eyes. Patients with asthma and chronic bronchitis are arriving with acute breathing attacks and chest tightness.

Doctors are also seeing people in their 20s and children with no prior medical history reporting throat distress and breathlessness after hours of outdoor exposure.

Dr. Bobby Bhalotra, senior consultant pulmonologist at Apollo Hospitals, Gurugram, said rising pollution had sharply increased OPD and emergency visits for respiratory distress, persistent coughing, watery eyes and bronchospasm-induced chest pain. “It is not just vulnerable groups, even individuals with no prior history of breathing ailments are suffering, while young children and patients with asthma or interstitial lung disease are bearing the brunt.”

Why is exposure to toxic air a health concern?

PM2.5 particles, measuring less than 2.5 micrometres in diameter, penetrate deep into the lungs and can enter the bloodstream, triggering inflammation and raising the risk of heart attacks, strokes and hypertension, besides respiratory damage, health experts said.

Prolonged exposure can impair lung development in children, increase chronic disease risks in adults and reduce life expectancy, including among non-smokers, they added.

“Prolonged exposure to air laden with carcinogens triggers immediate risks like heart attacks and low oxygen saturation, alongside lasting systemic damage. People must understand the social responsibility they carry; bursting firecrackers inflicts severe harm on future generations. Right now, vulnerable individuals and children should avoid stepping outdoors, run air purifiers indoors, and use N95 masks whenever transit is unavoidable,” Dr. Bhalotra said.

The potential consequences extend to reproductive health, too.

“This can lead to increased DNA fragmentation, free radical injury and oxidative damage, directly affecting male fertility. Therefore, air pollution and high AQI levels do not just affect the lungs; they can have a wider impact on various organs and systems of the body," said Dr. Vineet Malhotra, urologist, andrologist and sexologist at VNA Hospital.

Are fireworks solely responsible, or do winter weather patterns worsen the crisis?

Diwali fireworks and post-harvest crop burning add to pollution spikes, but the crisis has deeper, year-round sources: vehicle exhaust, road and soil dust, construction, industrial boilers, and the burning of municipal waste and biomass for heating, according to experts.

Winter weather compounds the problem. While warmer air helps disperse pollutants in summer, lower temperatures and slower winds in winter trap cold air beneath a warmer layer above. This inversion prevents pollutants from dispersing, keeping smoke, dust and toxic gases close to the ground. Seasonal fires thus aggravate an existing emissions burden, which remains trapped in the air people breathe.

What measures are in place to tackle the problem?

The government has introduced healthcare and pollution-control measures. All public hospitals are running dedicated CHEST (Cardio-respiratory Health Effects Screening and Treatment) clinics to diagnose and manage pollution-related illnesses, Mint reported earlier this month. Operating daily from September to February under National Centre for Disease Control (NCDC) guidelines, the clinics screen high-risk patients and track respiratory cases. They complement specialized pollution OPDs, including one at Ram Manohar Lohia (RML) Hospital.

The environmental response centres on the Graded Response Action Plan (GRAP), which triggers restrictions at specified air-quality thresholds. Measures include halting non-essential construction and demolition, restricting older diesel commercial vehicles, spraying water on roads and deploying mechanised sweepers to control dust. Authorities also shift primary classes to hybrid learning or close schools, advise remote work and inspect industrial units for the use of unauthorized fuels during severe pollution episodes.

But these interventions largely contain pollution after air quality deteriorates; they do little to eliminate the emissions accumulating through the year.

What will it take to break the cycle?

A lasting solution will require coordinated action across the entire airshed, not just Delhi's municipal boundaries, experts said. Priorities include replacing fossil-fuel buses and delivery fleets with electric vehicles, strengthening public transport to reduce private car use, and establishing mechanized agricultural residue collection systems. Industrial fuel monitoring must extend to small manufacturing clusters in neighbouring states, while paving road shoulders can help prevent loose dust from recirculating.

Dr. Soumya Swaminathan, former WHO chief scientist and former director general of the Indian Council of Medical Research, called for urgent and sustained action, including air purifiers in schools to protect children and N95 masks for high-risk groups outdoors.

“Delhi alone cannot solve this crisis; interventions must span the entire Indo-Gangetic airshed. While states have initiated plans with World Bank support, lasting improvement requires strict, multi-year enforcement across transport, industry, road dust, waste, and stubble burning.”

About the Author

Priyanka Sharma is a journalist at Mint, where she covers the Union Ministry of Health and the pharmaceutical industry. Her work focuses on explaining government policies and how they impact healthcare and the medicine market in India. With 12 years of experience in journalism, she has built a reputation for providing clear and honest news on important health topics that affect the entire country.<br><br>Her educational background includes a journalism degree from the prestigious Indian Institute of Mass Communication (IIMC) and specialized training in public health from the Public Health Foundation of India. Before her current role at Mint, Priyanka worked with India Today, The Pioneer, and ANI. She also served as a lead consultant for the National Health Authority, which gave her firsthand knowledge of how the government manages large-scale health programmes.<br><br>Priyanka is based in New Delhi and is an avid traveller who loves visiting the mountains. She has a great interest in regional flavours, particularly South Indian food.