It’s in the air!

The deteriorating air quality in Indian cities is contributing to the early onset of respiratory disease, cardiovascular disease and lung cancer in non-smokers according to a study published in The Lancet. In warmer climates, the impact of air pollution is exacerbated.

Dr Hari Kishan Boorugu, a consultant general physician at Apollo Hospitals, explains that at higher temperatures, sunlight interacts with the chemicals in exhaust gases to produce ground-level ozone, a common pollutant and powerful lung irritant.

Q.How does air pollution affect the human body?
Air pollution can cause several conditions that affect the respiratory system. High pollution levels increase the risk of chronic obstructive pulmonary disease independent of smoking history, and airway reactivity to allergens in patients with atopic asthma. Pollutants inhaled by a pregnant woman can affect the growth of the foetus and result in low birth weight, pre-term labour and other perinatal issues.

Q.How does particulate matter affect the body?
Particulate matter in the air can cause cardiovascular diseases. The pollutants with the strongest evidence for being health concerns include particulate matter (PM), ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2).

The health risks associated with particulate matter of less than 10 and less than 2.5 microns in diameter (PM10 and PM2.5 respectively) have been scientifically documented. These particles are capable of penetrating deep into the lung passageways and entering the bloodstream, thus causing cardiovascular, cerebrovascular and respiratory disorders. In 2013, such particles were classified as a cause of lung cancer by the World Health Organisation’s International Agency for Research on Cancer (IARC).

People who spend most of their time outdoors, including drivers, shopkeepers having establishments on the roadside, street vendors, children playing in parks close to vehicular traffic, and those whose jobs demand a lot of travel are at the highest risk of being affected by air pollutants.

Q.How do pollutants affect the vascular system?
Scientific evidence and experimental trials have shown that long-term exposure to air pollutants increases the risk of brain stroke and heart problems. It also creates a pre-existing condition for the development of heart diseases. While there is symptomatic evidence to support these observations, the exact mechanism remains unclear. More studies are required to understand how pollutants affect the vascular system.

Q.Does air pollution contribute to mental illness?
A recent study has shown that anxiety disorders may be related to exposure to air pollutants. Fine particulate matter in the air can affect people’s mental health. This is especially true in places where there is constant and continuous movement of vehicles, and places close to industrial zones.

Q.Why is it that some people are more prone to suffer from these diseases than others?
The tendency to be affected by air pollutants depends on the duration and intensity of exposure, the patient’s characteristics such as general health, age, immunity, and diseases, as well as pre-existing risk factors. In smokers and those whose health is already compromised due to diabetes or other metabolic disorders, the impact of exposure to pollutants is exaggerated.

Q.What are some preventive measures that people can implement?
At an individual level, you can reduce outdoor activity in areas of high pollution. Try to limit your outdoor activities to times when less vehicular movement is less. At a community level, you can reduce fuel consumption, improve public transport systems, and practice carpooling. The government should also implement strict industrial emission control measures.

Q.How can commuters protect themselves from vehicular pollution?
Wearing a mask can help filter particulate matter to some extent. If you’re on the road for long periods of time, you must work towards strengthening your immunity by ensuring you get enough sleep and maintaining a balanced diet. When you don’t get enough sleep, your immune system is compromised, which makes you more susceptible to diseases.