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Air pollution is truly a public health emergency in India and especially its national capital. Breathing polluted air is causing 16 times more deaths annually nationwide than deaths recorded during the COVID-19 pandemic, pediatrician Sanjeev Bagai revealed during a session at the ongoing Anil Agarwal Dialogue 2026 in Nimli, Rajasthan.
During the four years of COVID-19, about 600,000 deaths were recorded in India. However, annual deaths due to air pollution are 16 times higher than the average annual deaths during the COVID-19 period, said Bagai. Despite this, Indian hospitals do not have a specific diagnosis coding for air pollution in either inpatient or outpatient department records.
The national capital is faring worse. Just five winter months each year in the sprawling metropolis steadily shorten life expectancy. Exposure to air pollution during these five winter months in Delhi is estimated to be equivalent to smoking 9,000 cigarettes. This results in a loss of 129 days, or about 4.3 months, of life expectancy each year. Over a period of 30 years in Delhi, this could translate into a total loss of nearly 11 years of life, according to Bagai.
He said deaths caused by air pollution continue to be significantly underreported worldwide. Available data suggest that between 5 million and 8.1 million deaths globally each year are linked to air pollution. Citing the State Global Health Report 2020, he noted that in India alone, 2 to 3 million deaths annually have been recorded due to air pollution.
According to Bagai, based on The Lancet 2021 and Indian Council of Medical Research 2019 data, between 18 and 25 per cent of all deaths are attributable to air pollution. Referring to research from the University of Chicago, he said air pollution reduces adult life expectancy by 8 to 10 years per person. Citing the Lung Foundation of India, he added that 30 per cent of children in Delhi have been found to suffer from irreversible lung damage.
Bagai asked, “Does anyone know what India’s health budget is? It is just a little over Rs 1 lakh crore. Do you know how much productivity India loses every year due to air pollution? Around Rs 24 lakh crore, which is about 8 per cent of Gross Domestic Product. Would it not be wiser, more cost-effective and more humane to tackle air pollution instead of ignoring it? This annual loss is nearly 24 times the total health budget.”
In many regions, there is neither an adequate hospital system nor proper IT infrastructure or documentation. “How will we collect data? We simply write ‘respiratory failure’ and move on. I can confidently say that the figure of 2 to 3 million deaths in India will double or triple once we begin properly documenting conditions like asthma and cancer that are actually caused by air pollution,” said Bagai.
Speaking about exposure, he said pollution levels increase with rising relative humidity, especially in the morning when children go to school. Citing a survey, he said many children either avoid going to school or wish to leave Delhi because of pollution.
Referring to a November 2022 report in The Lancet, he said the duration of exposure is crucial. More than 15 minutes in highly polluted air can trigger respiratory distress. Continuous exposure for one to two days can cause myocardial infarction (heart attack) and stroke. Three to five days of sustained exposure can even lead to sudden cardiac arrest.
The pediatrician noted that municipal corporations still follow outdated road-cleaning methods. Dust is first settled and then swept back into the air, where it remains suspended for hours, affecting everyone.
Particulate matter 2.5 (PM2.5) particles are about one-fourth the size of a strand of hair and are extremely small and dangerous. Studies suggest that underreporting may be as high as 20 per cent. Bagai emphasised the direct link between PM2.5 exposure and mortality.
According to him, every 10 per cent rise in PM2.5 levels can double mortality risk. An increase of 5 micrograms per cubic meter in PM2.5 concentration raises mortality by 4 per cent; 10 micrograms per cubic meter increases it by 8 per cent; and 35 micrograms per cubic meter can raise mortality by up to 24 per cent.
Citing research published in Nature, he said every 1 microgram per cubic meter increase in PM2.5 is associated with 12,000 additional deaths annually. A 1 per cent increase in carbon monoxide (CO), nitrogen oxides (NOx), and sulphur oxides (SOx) doubles the risk of heart attack and stroke.
He added that the duration of pollution exposure is associated with a 0.003 to 0.08 per cent rise in mortality, and a one-unit increase in pollution corresponds to 1,200-1,600 additional deaths. A 1 microgram per cubic meter increase in PM2.5 is linked to a 0.073 per cent rise in mortality. Increasing tree cover has been shown to reduce black carbon levels by 48 to 57 per cent. Pollution has been associated with 10.65 times higher disease burden, and a one-unit rise in PM2.5 leads to 8.4 per cent more recorded illnesses.
“Do not link air pollution only to the lungs,” Dr Bagai said. “It affects the immune system, increases infections and impacts almost every organ system. It causes anemia, insomnia and heightened vulnerability in children. Children have limited immunity and inhale more pollutants relative to their body weight.”
According to data from the Indian Institute of Technology Delhi, PM2.5 causes cardiac inflammation, activates platelets and leads to thrombosis and arrhythmias, said Bagai. It affects the lungs, causes asthma, damages children’s respiratory systems and contributes to Alzheimer’s disease, dementia, depression, mood swings, cognitive decline, autism in children, stroke, Parkinson’s disease and neurodegeneration.
Displaying images of two lungs during the session, Bagai explained that in polluted lungs, alveoli are damaged. Reactive cytokines are released, causing inflammation and oxidative stress. The lungs attempt to compensate, but eventually the heart, kidneys, brain and metabolic systems are affected.
A July 2024 report in The Lancet, said Bagai, noted that 11 per cent of total deaths in Delhi are attributable to PM2.5. Every 10 microgram per cubic meter increase in PM2.5 raises mortality by approximately 3.6 per cent.
He stressed that ample data are available linking air pollution to deaths and disease.
Some studies equate specific increases in AQI with cigarette smoke exposure. During Delhi’s winter months, cumulative exposure is extremely high. Referring to research by Berkeley Earth, Bagai said a full-day exposure to 22 micrograms per cubic meter of PM2.5 carries a health risk equivalent to smoking one cigarette. For instance, eight hours of exposure at 60 micrograms per cubic meter equals one cigarette, while at 511 micrograms per cubic meter it is equivalent to eight cigarettes.
In Beijing, China, average exposure of 120 micrograms per cubic meter for eight hours equals four to five cigarettes, and at higher levels, this may rise to 25 to 60 cigarettes. According to the Canadian Air Quality Health Index (AQHI), 24-hour exposure at level 1 (10 micrograms per cubic meter) equals 0.5 cigarettes; level 6 (60 micrograms per cubic meter) equals 2.7 cigarettes; and level 10 (100 micrograms per cubic meter) equals 23.2 cigarettes.
Bagai said air pollution also affects pregnancy, damaging fetal organs. It is linked to preterm birth, autism spectrum disorders, infertility, maternal hypertension, placental complications and increased premature mortality. Even after birth, lung development in children can remain impaired for years.
Exposure to pollution increases the risk of congenital heart disease. Stillbirths may rise by about 14 per cent. Structural abnormalities such as cleft lip, absent ears, microcephaly or macrocephaly, spinal deformities, single kidney or absent bladder have been observed.
If a woman has been exposed to pollutants 12 months before conception, genetic changes may already have begun. Moving to cleaner air during pregnancy may not fully reverse earlier exposure.
He said air pollution is neurotoxic due to oxidative stress. It increases the risk of motor neuron disease, dementia and memory loss. It affects the heart, blood pressure, type 2 diabetes risk, kidneys (including chronic kidney disease and higher dialysis risk) and bone density, leading to osteoporosis and fractures.
Alongside air pollution, the microplastic crisis is rapidly emerging. Microplastics are now being found deposited in heart arteries. Citing Toxicology Science 2024, he said microplastics have reached the brain, liver, placenta, kidneys and coronary arteries. They have been detected in 40-60 per cent of people. A 2.1-fold increase in cancer and heart attack cases is projected over the next three years. Between 2016 and 2024, microplastic levels in the human body have increased by 20 per cent.
In 2019, global microplastic production was estimated at 6 billion tonnes per year. These particles can take up to 500 years to fully degrade. About 84 per cent originate from waste dumps. Air samples show filament fibers 1-5 micrometers thick, with concentrations ranging between 25 and 5,000 micrograms per cubic meter. An average person inhales approximately 75,000 to 120,000 microplastic fibers annually. These enter the body through inhalation, ingestion and skin contact and persist for generations in the environment.
“The plastic waste we release into the air first settles into soil and eventually into water. The cycle continues,” Bagai said. Micro and nano plastics have increased dramatically over decades. They are not biodegradable and can remain in the body for decades.
Plastic waste persists in the environment for centuries and can remain in arteries for years. Microplastics have been found in heart attack patients and are linked to hypertension and other cardiovascular problems. Plastic bottles, especially when exposed to heat and sunlight, release microplastics into liquids. Indoor air also contains micro and nano plastics. Heavy metals can bind to microplastics, forming positively charged particles that adhere to negatively charged cell membranes and persist in the body.
Common chemicals in plastics include bisphenol A (BPA) and phthalates. BPA mimics estrogen by binding to estrogen receptors and has been linked to miscarriage, stillbirth and structural abnormalities in newborns.
Plastic exposure can damage the gut lining, increasing permeability. The gut, often referred to as the “second brain,” is severely affected. Thick plastic bottles and prolonged storage increase chemical leaching. Many bottles are exposed to heat before sale, further increasing contamination.
Bagai warned that children are being born with severe abnormalities, including hydrocephalus and other congenital defects, requiring multiple surgeries and lifelong care. Projections for the coming years are alarming. As pollution levels rise sharply, strong policy measures, a clear public agenda and firm financial commitment are urgently needed.
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