Major Indian metropolitan cities are reeling under the effects of severe air pollution, euphemistically called ‘smog’, this phenomenon occurs every year during winter. This has deleterious effects not only on the respiratory system, but as recent studies show, also on the cardiovascular health of people living in urban areas.
Excessive air pollution is associated not only with respiratory diseases like bronchitis, asthma and lung cancer, but also cardiovascular diseases. Recent studies show that air pollution behaves akin to cigarette smoke and can cause plaque rupture and precipitation of acute coronary syndromes including myocardial infarction.
In addition, air pollution is also associated with chronic lifestyle disease like hypertension and diabetes.
In winter, the phenomenon of ‘Temperature Inversion’ intensifies air pollution. Burning of coal, kerosene, wood, and garbage, along with vehicular exhaust fumes gives rise to suspended particulate matter. These particles are responsible for these pollutants being dispersed in the air.
An index of these pollutants is at PM 2.5, which refers to the size (2.5 microns or smaller) of the particulate matter suspended in air. These are microscopic “respirable” particles, i.e. they are so small that they cannot be filtered by the respiratory defence mechanisms like vibrissae (nasal hair) or cilia.
These can damage the small air sacs in the lungs called alveoli, and are then absorbed into the blood stream. These are responsible for the most toxic and adverse effects of air pollution.
A safe level of PM 2.5 is lower than 50. Indeed, most busy metropolitan cities are able to keep these values low even though they are densely populated using a combination of Anti-Pollution legislation and other methods. Metros like Beijing, New York, London have their PM 2.5 lower than 50.
If you take a look at the PM 2.5 in India though, New Delhi, Mumbai and other metros they contain these values beyond the safety limit. Mumbai, for example, has PM 2.5 value at 194 today, which falls in the dangerous category.
So how can we protect ourselves from the deleterious effects of atmospheric pollution?
Here are three simple ways.
- Monitor PM 2.5 levels in the atmosphere. Many Apps, including Google Weather gives these values dynamically.
- Avoid outdoor activities when PM 2.5 levels are high.
- Use air conditioning and air purifiers to combat air pollution.
The author is an interventional cardiologist and heart failure specialist.