Ozone levels in the capital have steadily increased this summer — doubled even at some locations — soon after the heat wave hit the city in May this year, the latest analysis by the Centre for Science and Environment has revealed.
Residential areas of RK Puram and Punjabi Bagh have high ozone concentrations, much higher than commercial and transport hubs like Anand Vihar, the CSE report said. Ozone aggravates respiratory problems, especially chronic obstructive pulmonary disease, the report states.
Analysis of real-time air quality data has shown that the share of days violating the eight-hour CPCB standards of 100 microgramme per cubic metre in February was 12 per cent, which increased to 19 per cent in March, 52 per cent in April, and alarming levels of 77 per cent in May.
“On several occasions and several locations, very high peak levels — three times the standards — have been noted. This is of serious concern as even short duration exposure to high ozone levels can cause great harm. This is one of the reasons why ozone standards are set for eight-hour average as well as one-hour average,” the CSE said in a statement.
Further, this April and May have seen more number of days violate the eight-hour standard, which is higher this year compared to last year. “In 2017 summer, as much as 64 per cent of the days during April and May violated the standard as opposed to 50 per cent of days during April and May in 2016. The problem is growing steadily,” the analysis revealed.
“Delhi and NCR are in the grip of multi-pollutant crisis,” CSE’s executive director Anumita Roychowdhury said.