Delhi AQI plunges to ‘severe’ post-Diwali, doctors warn breathing air now is as harmful as smoking dozens of cigarettes

A thick blanket of smog engulfed Delhi-NCR on Tuesday morning, with the Air Quality Index (AQI) once again slipping into the “hazardous” category after Diwali celebrations. According to real-time monitoring, India’s PM2.5 level stood at 81 µg/m³ and PM10 at 142 µg/m³, putting air quality firmly in the hazardous zone.

Doctors and environmentalists are calling it a “wake-up call” for residents, warning that even short exposure can cause harmful effects, particularly for children, the elderly and those with existing health conditions.

What Are PM2.5 and PM10 — And Why They Are Dangerous

Particulate matter (PM) refers to fine inhalable particles present in polluted air. PM10 includes larger coarse particles, while PM2.5 represents tiny, microscopic particles that can penetrate deep into the lungs and enter the bloodstream. Prolonged exposure has been linked to respiratory illnesses, cardiovascular disease, strokes and even cancer.

Early warning signs include:

• Coughing, wheezing and chest tightness
• Sore or scratchy throat
• Shortness of breath
• Irritated eyes and skin
• Increased phlegm or worsening asthma symptoms

Experts Sound Alarm

Dr Harish Chafle, Senior Consultant, Gleneagles Hospitals, told LiveMint: “High AQI exposure can affect respiratory or cardiovascular health within hours. Studies show that breathing Delhi’s toxic air can be as harmful as smoking multiple cigarettes a day.”

Environmentalist Bhavreen Kandhari told PTI, “With nearly every monitoring station in Delhi now in the red zone and AQI soaring past 300, this is a wake-up call. Today’s smog isn’t just clouding the sky; it is choking our children’s lungs.”

Respiratory medicine specialist Dr Nikhil Modi of Apollo Hospitals explained why the crisis worsens in winter: “As the air cools, wind speed decreases and cold air traps pollutants at lower levels. After Diwali, pollution always spikes. We are already seeing patients with coughing, watery eyes and breathing difficulties. Children and elderly people should avoid stepping outdoors and wear masks if they must.”

Why Even A Morning Walk Can Be Harmful

Doctors strongly advise against outdoor exercise during high AQI days:

• Increased inhalation: During physical activity, breathing rate increases up to five times, pulling in more pollutants.
• Deeper penetration: Exercise often involves mouth breathing, bypassing the nose’s natural filters.
• Intensified damage: Exercise heightens oxidative stress and inflammation, which pollution amplifies further.

This means that a simple morning jog or brisk walk can significantly increase the dose of pollutants inhaled, causing irritation, triggering asthma or raising cardiovascular risks.

Who Is Most At Risk?

• People with heart and lung disease: Air pollution worsens asthma, COPD, arrhythmia and can trigger heart attacks.
• Older adults: Reduced lung function, weaker immunity and chronic illnesses make them highly vulnerable.
• Children and infants: Developing lungs and higher breathing rates mean greater exposure per body weight.

What Happens Inside Your Lungs

When toxic particles are inhaled, they cause inflammation, swelling and excess mucus production in the airways. Over time, this weakens lung function and increases the risk of chronic conditions like asthma, COPD and emphysema. The smallest particles bypass the lungs and enter the bloodstream, causing systemic issues including heart disease, stroke and dementia.

Doctors’ Advice To Residents

• Avoid outdoor activities, especially in the early morning.
• Wear N95 or N99 masks if stepping out is unavoidable.
• Use air purifiers indoors.
• Keep medications for asthma or allergies ready.
• Children, the elderly and those with chronic illnesses should stay indoors.

Advice for senior citizens

Dr Chafle says, "When the Air Quality Index (AQI) is high, senior citizens can take specific steps to minimise their exposure to air pollution from home. These measures focus on improving indoor air quality, reducing pollutant sources, and supporting overall health.

• Controlling indoor air: Use an air purifier. Invest in a high-efficiency particulate air (HEPA) air purifier to filter out fine particulate matter (PM2.5) and other pollutants. Keep windows and doors closed. When the AQI is high, close all windows and doors to prevent polluted outdoor air from entering your home.
• Maintain and use your HVAC system. Run your air conditioning continuously on the recirculation setting to filter indoor air. If possible, install a high-efficiency filter rated MERV 13 or higher.
• Clean and change filters regularly. To ensure proper function, regularly replace the air filters in your heating, ventilation, and air conditioning (HVAC) system.
• Create a clean room. If you cannot filter your entire home's air, designate one room as a "clean room" for sleeping and resting.

For senior citizens who must go outside during high air quality index (AQI) conditions, Dr Chafle suggests that combining a high-quality mask with strategic timing and travel can significantly reduce exposure.

Advice for parents

Dr Chafle advised, “Parents can protect children from air pollution by monitoring the Air Quality Index (AQI) and limiting outdoor time on high-pollution days, advocating for cleaner indoor environments with air purifiers and proper ventilation, and ensuring children wear well-fitting N95 or certified masks when they must be outside. It's also crucial to choose routes away from heavy traffic, take shortcuts for walks and encourage a healthy lifestyle with good nutrition to boost immunity. ”