As temperatures in the city have begun to fall, there has been a significant rise in the amount of dust and other suspended particles in the air in the past two weeks.
According to last week’s continuous air monitoring data of the state pollution control board, the concentration of dust or respiratory suspended particulate matter (RSPM) at Sion, Bandra and Worli has been between 150 micrograms per cubic metre (ug/m3) and 300 ug/m3 as against the permissible limit of 100 ug/m3. Similarly, levels of nitrogen oxide emitted largely from vehicles at these three locations were between 100 ug/m3 and 200ug/m3.
“Weather plays an important role in the concentration of pollutants. In winter, the level of pollutants rises because of the inversion phenomenon,” said Rakesh Kumar, National Environment Engineering Research Institute (NEERI), Worli.
According to Kumar, air near the Earth’s surface is warmer as compared to the upper atmosphere. “But during inversion, cold air present near the Earth’s surface gets trapped under warmer air. As a result, hot and cold air does not mix easily in the upper atmosphere and pollutants get trapped in the lower atmosphere,” said Kumar.
Doctors said an increase in pollution levels also leads to a rise in the number of patients suffering from bronchitis and respiratory disorders. “In winters, approximately 40% to 60% of patients come with upper and lower respiratory infections, asthma and chronic obstructive pulmonary disease (COPD),” said Dr Jaydeep Trivedi, a consultant.
The most common diseases affecting people in the city are cold, cough, sore throat, viral infections and respiratory disorders such as sinus and asthma. “It’s because the influenza virus is very active in winter,” said Dr Vimal Pahuja, general physician at Dr LH Hiranandani Hospital, Powai.
Dr Pahuja added that people are prone to stroke and pneumonia in winter. “Blood gets thicker as the temperature falls, increasing chances of stroke, chest pain and heart attack.”