Air pollution in Delhi, which is already at levels harmful for health, is likely to worsen after Diwali.
PM 2.5, minuscule particles that make the air hazy and can have an adverse effect on health, will be seven times its safe limit. The air pollution forecast issued by System of Air Quality and Weather Forecast (SAFAR) of the ministry of earth sciences, also issued a health warning, saying that there is serious risk of respiratory problems among the people after prolonged exposure.
On Thursday, the day after Diwali, PM 2.5 levels will increase from the average of the last 10 days by 148%, and PM 10 (bigger at 10 microns) levels are going to increase by 170%, according to SAFAR. While PM 2.5 will be 430µg per cubic metre, which is more than seven times the safe limit of 60µg per cubic metre, PM10 will be 956µg/m3, which is more than nine times the safe limit of 100 µg/m.
“There is enough moisture in the air and atmospheric holding capacity is quite high for particles emitted from firecrackers. In all likelihood, air quality during this year’s Diwali is going to be inferior to that of last year owing to cooler temperature and downward shift of inversion layer,” said Gufran Beig, chief project scientist at SAFAR.
This year, Diwali is expected to be colder than last year. Beig said that particles from fireworks will sit on water droplets, resulting in more particles in suspended air. It would mean a dense haze.
The peak hours of pollution are expected to be 10pm to 2am and 7 am to 9 am on Wednesday and Thursday, respectively. While Noida on the outskirts of Delhi and the north campus of Delhi University are expected to be the most polluted areas in the national capital region, Lodhi Road and Mathura Road would be the least polluted.
In 2014, a World Health Organization study in May and a Yale study in February found the air in New Delhi to be the most polluted in the world. There were 12 other cities in the top 20 most polluted cities among 1,600 cities studied.
The health effects of particulate matter exposure range from respiratory and cardiovascular morbidity, such as aggravation of asthma and respiratory symptoms to even lung cancer.