Delhi’s traffic hot spots suffer ozone pollution: DPCC report

New Delhi
Dangerous concentrations of ground-level ozone (O3) gas was recorded for 56 days in Nehru Nagar in April and May 2023, for 45 days at Patparganj and 38 days at Aurobindo Marg — all traffic hot spots — according to a report dated September 2 submitted by the Delhi Pollution Control Committee (DPCC) to the National Green Tribunal on Thursday.
The highest concentration, 224.9 micrograms per cubic metre (µg/m3), was recorded at Nehru Nagar, located near Lajpat Nagar. This was followed by a peak average of 188.3µg/m3 at Patparganj and 175.4µg/m3 at RK Puram, according to the report. All of these exceeded the national permissible standard of 100µg/m3 for an eight-hour period.
To be sure, higher concentrations of ground-level ozone cause difficulty in breathing and both long-term and short-term respiratory damage.
“CPCB data shows that the Nehru Nagar, Dr. Karni Singh Shooting Range, Jawaharlal Stadium, Major Dhyan Chand National Stadium, Nehru Nagar and RK Puram saw high ozone levels, which was more than the national ambient air quality standards of 100 micrograms per cubic metre (µg/m3) for eight hours. The ozone levels were at peak during 11am to 6pm,” DPCC’s report said.
DPCC said the highly volatile gas is produced from a complex interaction between nitrogen oxides (NOx), volatile organic compounds (VOCs) and carbon monoxide emitted from sources, such as vehicles, industries and factories. The gases undergo cyclic reactions in the presence of sunlight, producing ozone at the ground level, the pollution body said, stating both short-term and long-term measures were being taken to regulate these sources.
An eight-hour analysis at 24 air quality monitoring stations in April and May 2023 found other stations exceeded permissible limits too — Mundka recorded 23 days, Alipur 29 days, Dr Karni Singh Shooting Range 32 days, Mandir Marg 25 days and RK Puram 20 days, the report said.
The report comes in response to the directions of NGT to DPCC and the Commission for Air Quality Management (CAQM) in April, seeking measures to reduce the impact of the gaseous pollutant, which is at its peak in summer.
DPCC said action was being taken against vehicular pollution, industries, open burning and other localised combustion sources. To check on vehicular pollution, 385 transport department teams and Delhi Traffic Police teams were on the ground, with 14,294 old diesel and petrol vehicles impounded in 2023. This year, 308 such vehicles were seized, it said, adding 4.97 million PUC (pollution under control) certificates were issued in 2023 and 2.45 million so far this year. Other action includes challan on unauthorised parking and non-destined goods vehicles.
Further, an action plan was put in place for 134 roads that regularly witness heavy congestion, with over 2,000 traffic personnel deployed there and to reduce emissions, an e-vehicle policy was also in place, accounting for over 14.5% of new vehicles registered in 2023, DPCC said.
CAQM, in a separate submission, said it issued a comprehensive policy — with sector-wise action plans for prevention and control — to curb air pollution in the national capital region in July 2022. “The commission also issued 82 statutory directions, 15 advisories in addition to various orders/guidelines for the control of air pollution in national capital region,” CAQM said in its report dated August 30.
In a study released last month, the Centre for Science and Environment (CSE) assessed India’s major metropolitan cities, finding Delhi-NCR the most impacted region in terms of high ground-level ozone. Between January and August, Delhi-NCR recorded 176 days of higher-than-permissible ground-level ozone.
“Ground-level ozone is a highly reactive gas and has serious health consequences. Those with respiratory conditions, asthma and chronic obstructive pulmonary disease — as well as children with premature lungs and older adults — are at serious risk,” said CSE’s Anumita Roychowdhury, calling for consistent efforts throughout the year against sources contributing to ozone formation.