Air Pollution Trend and Variation during a Mega Festival of Firecrackers (Diwali) in Context to COVID-19 Pandemic

The present study was conducted in Lucknow city to assess the impact of firecracker burning during Diwali, from 2 November 2021–6 November 2021 including the pre and post-Diwali days. The concentrations of PM 10 , PM 2.5 , SO 2 , NO 2 , CO, O 3 , benzene and toluene, were monitored from the Central Pollution Control Board site on an hourly basis. The Air Quality Index was also recorded for PM 10 , PM 2.5 , SO 2 and NO 2 . A questionnaire survey was done with 51 doctors to know the reported complaints post-Diwali. On Diwali night the PM 2.5 value reached 262 µg m −3 around 22:00 hours and the maximum value (900 µg m −3 ) was obtained on 5 November, reported from the Central School monitoring station. From Gomti Nagar highest PM 2.5 value obtained on Diwali day was 538 µg m −3 at 23:00 hours reaching 519 µg m −3 post-Diwali. Areas belonging to the old part of the city witnessed higher variations as PM 2.5 crossed 900 µg m −3 , in Lalbagh and Talkatora areas. The multivariate analysis showed that on Diwali night there was an increase of 204, 386, 344 and 341 in the PM 2.5 concentration reported from Gomtinagar, Central School, Talkatora and Lalbagh stations, showing that firecracker burning resulted in a significant increase in air pollution. The Toluene/Benzene ratio was mostly more than 1 indicating that toluene and benzene may be emitted from other sources as well including the mobile sources. Around 50–75% rise was seen in the number of patients post-Diwali. 57.1% of the reported cases had respiratory issues, followed by allergic reactions. The data obtained from Lalbagh, Talkatora and Central School showed that although the values remained high, a decreasing trend was seen in the AQI compared to previous years which is a good sign and may be attributed to public awareness and the ongoing pandemic making people conscious.