Every year, the night sky becomes a canvas of colours, and within hours, the air becomes heavy. Fireworks release a dense mix of fine dust, metal particles, and gases. We see the sparkle, but not the storm of chemicals that follows.

According to a 2020 study in the Atmospheric Environment, air pollution during Diwali nights in Delhi spikes up to 16 times higher than normal. These aren’t just numbers; they represent the toxic air your lungs are forced to take in.

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What happens inside your lungs

The smoke from firecrackers contains PM2.5, tiny particles smaller than a red blood cell. When you inhale them, they bypass your nose and throat, settling deep in your lungs where they can’t easily escape. A review published in Frontiers in Public Health (2014) found that exposure to fireworks increases coughing, wheezing, and asthma attacks, particularly among children and the elderly.

Another Indian study measured personal exposure during Diwali and found PM2.5 levels between 1,800 and 39,000 µg/m³, thousands of times higher than WHO’s safe limit. Even a few hours of exposure can irritate the airways, trigger inflammation, and lower lung function for days. For people with asthma or bronchitis, that means breathing trouble long after the celebration ends.

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The hidden hit to your heart

The heart isn’t immune. Once those fine particles enter your bloodstream, they can damage blood vessels, raise blood pressure, and affect heart rhythm.

Research in Environmental Health Perspectives (2021) showed that short-term spikes in particulate matter increase the risk of heart attacks and arrhythmias. The American Lung Association also warns that firework smoke can worsen existing lung diseases and trigger cardiac events. In simple terms, what you breathe doesn’t stay in your lungs; it travels through your blood, and your heart ends up paying for it.

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Who’s most at risk

• Children, because their lungs are still developing, and they breathe faster.
• Elderly adults, whose heart and lung capacity are already reduced.
• People with asthma, COPD, or cardiac disease, for whom even brief exposure can cause complications.
• Outdoor workers and street vendors, who stay in polluted air longer.

Infants are especially vulnerable since their immune systems aren’t mature enough to fight air toxins.

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The chemistry behind the colours

Those vibrant firework hues come from metals like barium (green), copper (blue), strontium (red), and aluminium (white). They make the sky beautiful, but the air toxic. Once inhaled, these metals don’t leave easily. Barium strains the lungs, copper causes cell damage, lead harms the heart and brain, and strontium settles in bones. Our bodies can’t effectively flush them out, so they slowly build up. A 2025 study in Atmosphere found that levels of heavy metals, such as barium, copper, and lead, increased significantly during fireworks shows in California.

Even green crackers, often promoted as safer, still emit harmful gases and fine particles. As IIT Bombay scientists clarified, green means less pollution, not no pollution.

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Air pollution already causes over 1.6 million deaths annually in India, according to The Lancet Planetary Health (2018). Firecracker smoke adds an intense, avoidable layer to that problem. Clean air isn’t about being anti-fun; it’s about protecting what’s most basic: the ability to breathe without pain. Celebrating mindfully ensures the joy lasts longer than the smoke.

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Take your first step with a health check that helps you choose the plan that best suits you.