The air quality in Delhi-NCR has again deteriorated to ‘severe’ and ‘hazardous’ levels. The reason is the frequent dust storms that the capital has been facing recently. This ground level dust storm has increased suspended particulate matter in the air, particularly PM10, with levels higher than 500 and even crossing 800. Levels of PM 2.5 are not so high at less than 100.

AQI ranging between 0-50 is considered good, 51-100 satisfactory, 101-200 moderate, 201-300 poor, 301-400 very poor and 401-500 severe.

This picture is typically seen in construction sites, which generate high levels of dust. Dry sweeping also produces a significant amount of dust. Total VOCs may be normal in conditions of high dust levels.

Particulate matter or suspended particles less than 10 micrometer in diameter are called PM-10. When inhaled, they remain in the lungs and can damage the lining of the respiratory tract and lung alveoli and reduce lung capacity and exercise capacity causing asthma and COPD. Later on they may permanently damage the lungs.

PM2.5, on the other hand, is absorbed, enters the circulation and affects mainly the heart. It increases blood pressure and may cause heart attack and stroke.

Dust particles irritate the eye and also the airways and cause coughing, wheezing. The public should avoid exposure to such high levels of pollution. Patients of asthma and COPD in particular should take caution. They may need to increase the dose of their medications.

Dr KK Aggarwal

Padma Shri Awardee

Vice President CMAAO

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Immediate Past National President IMA