Not just organs, pollution can cause cellular damage too: Experts

The journal Chest, the official publication of the American College of Chest Physicians, highlighted in its review earlier this year that exposure to fine particulate matter (PM) 2.5 or less is the fifth leading risk factor for death in the world.

Breathing in high volumes of heavily polluted air for a prolonged period adversely affects not just the organs in your body but also causes damage at the cellular level, say experts.

Tourists, with their faces covered with masks, at Delhi’s Red Fort on November 2, 2019, as the national capital’s air quality continued to be in the ‘severe’ zone. (Sonu Mehta / Ht Photo)

The journal Chest, the official publication of the American College of Chest Physicians, highlighted in its review earlier this year that exposure to fine particulate matter (PM) 2.5 or less is the fifth leading risk factor for death in the world.

In the recent Global Burden of Disease data analysis as well, more than one million premature deaths were attributable to ambient air pollution in 2015 in India. Your lungs, heart and the brain are worst sufferers when pollution levels peak as very fine PM particles can find their way into the circulatory system and damage the organs.

Chokes the lungs

The respiratory system comprises nose, throat, respiratory tubes and the lungs. The PM 2.5 and 10 microns are considered dangerous as they are of respirable size and can travel down to the lowest part of the lungs where gas exchange takes place.

“When we say PM 2.5 or 10, it is only the size of the particle we are talking about and the kind of damage afflicted depends on the source of these particles, such as firecrackers, fuel combustion, stubble burning, etc. PM formed due to diesel or kerosene burning can cause lung cancer,” says Dr GC Khilnani, former head of pulmonology department, All India Institute of Medical Sciences (AIIMS).

The damage starts with inflammation of the airway, and finer the particulate matter the deeper it penetrates. “What nobody talks much about but who do the maximum damage are ultrafine particles of 0.1 micron or less. These penetrate the lungs and reach the blood stream. Once they are in your blood, these can go anywhere – the brain, the heart, kidneys, etc.,” said Dr Khilnani,

Harms the heart

Breathing in heavily polluted air can cause irreversible damage to the arteries as well.

“When these fine particles that lungs aren’t able to filter reach the blood stream, these get attached to the blood vessel walls – the arteries. Over a period of time, there can be a clot formation inside the vessel that can lead to blockage. There can be a sudden narrowing of the blood vessels that can eventually lead to a heart attack,” said Dr Upendra Kaul, senior cardiologist, Batra Hospital & Medical Research Centre.

It can lead to an unstable angina – not enough blood and oxygen flow to the heart causing a heart attack. In patients who already have blockages, exposure to pollutants tends to accelerate the process.

Respiratory diseases can also cause damage to the heart.

“Chronic bronchitis also leads to heart disease, though of a different kind. It’s called cor pulmonale, or enlargement of the heart,” adds Dr Kaul.

Brain damage

The brain is also not spared from the adverse effects of pollution. “When the heart malfunctions, it automatically affects the brain functioning as well, as blood or oxygen flow to the brain becomes restricted, which can lead to a stroke. Also, inhaling pollutants emits certain chemical responses within the body which can also cause a stroke over a period of time,” says Dr Deepak Aggarwal, professor, neurosurgery, AIIMS.

Since pollutants affect a person’s immunity, it can also cause autoimmune disorders.

“Exposure to pollutants can also lead to a condition called vasculitis, which is inflammation of blood vessels that leads to thickening, weakening, narrowing or scarring of the vessels. This could also lead to a stroke,” he added.