NEW DELHI : A thick blanket of smog continues to envelop Delhi as the city recorded the highest level of pollution this season, with air quality in ‘severe’ category for the third consecutive day.
According to System of Air Quality Weather Forecasting and Research (SAFAR) of the Union ministry of earth sciences, the Air quality index (AQI) remained above ‘400’ on Wednesday, considered to be ‘severe’ when experts recommend even healthy people to avoid any outdoor physical activity, which could otherwise lead to itchy throats, dry cough or difficulty in breathing. The effects can be more pronounced on those already vulnerable children and older adults, or those with respiratory problems.
The visibility remained poor during the early hours on Wednesday, as thick haze shrouded the city. The AQI was recorded at ‘423’ for Delhi around noon, with the highest level of ‘462’ recorded for the monitoring station at Delhi University. The air quality remained ‘very poor’ in neighboring Gurugram at ‘391’, but the worst for Noida, where it breached the ‘500’ mark, and hovered around ‘515’.
“The wind speed had dropped significantly since last few days and its not favouring the dispersion of pollutants accumulated in the air during Diwali. The impact of stubble burning incidents is also being seen quite prominently. The situation may improve slightly if wind gain speed but even that does not bring any relief as it is still likely to remain ‘very poor’ which is a matter of concern,” said Vijay Soni, senior scientist at India Meteorological Department (IMD).
According to the weather department, no major change in temperatures is expected over the next two days, after which they could dip by at least 2 °C. Any lowering of temperature would only worsen the situation.
The average concentration of PM2.5 was recorded at a hazardous level of ‘273’, while it was ‘421’ for PM10. Several published studies have established a strong correlation between ambient PM concentrations and increase in mortality and hospitalizations due to respiratory diseases.
PM2.5 (smaller than 2.5 micrometres) is of specific concern because it contains a high proportion of various toxic metals and acids, and can penetrate deeper into the respiratory tract. Long-term exposure to PM10 is linked to effects on breathing, respiratory symptoms, decrease in pulmonary function and damage to lung tissue and cancer.