The hullabaloo around air pollution might have died down with the advent of summer but the searing temperature has led to another environmental hazard in New Delhi and and the National Capital Region (NCR): The ozone pollution.
Ozone has emerged as a dominant pollutant along with particulate matter on at least 28 days during summer of 2019 as opposed to only 17 days in 2018 summer, says an analysis by Centre for Science and Environment (CSE).
Ozone is a deadly gasthat cancause serious health implications,especially to those suffering from asthma and respiratory conditions. Evenan exposure for ashort duration can lead to emergency hospital admission.
Ozone is not emitted directly from any source. Gases such as nitrogen oxide and volatile organic compounds that are emitted from combustion sources such as vehicles, industry or power plants, react in the air under the influence of sunlight and temperature to form ozone.
"Even as Delhi is battling serious particulate pollution, newer rogues are beginning to raise their ugly heads to add to the health risk. Ozone pollution can be a serious health crisis if the short duration levels begin to increase hereafter," says Anumita Roychowdhury, executive director (research and advocacy), CSE.
CSE tracked the daily ozone data released by the Central Pollution Control Board (CPCB) for Delhi and the National Capital Region (NCR) for the period betweenApril 1 andJune 15 this year.
Ozone level in Delhi exceeded the standard average for 16 per cent of the days. The percentage of days was higher in several residential and industrial locations. In Siri Fort, it was highfor 76 per cent of the days followed by Sri Aurobindo Marg (87 per cent), R K Puram (53 per cent), JLN Stadium (71 per cent), Dwarka Sector 8 (68 per cent) and Rohini (63 per cent).
The industrial and institutional areas are in an equally bad situation: Bawana (78 per cent of the days in the period under analysis), Jahangirpuri (67 per cent), Najafgarh (92 per cent), and Narela (80 per cent). This is bad news as it indicates increased and extended exposure for people living in these areas almost on a daily basis.Among key NCR towns, Faridabad has experienced the highest share of days - 80 per cent - when ozone crossed the eight-hourly standards, followed by Ghaziabad with 67 per cent and Gurugram with 21 per cent of days. Surprisingly, Noida shows much less impact with only 1 per cent of the days exceeding the standards.
The eight-hour average standard for ozone exposure is 100 microgram per cubic metre (cu m). The highest concentration in 2019 went up to 122 microgram per cu m, which is 1.22 times higher than the eight-hour average standard. During 2018, it had gone up to 106 microgram per cu m which is 1.1 times higher than the standard. This will require strong action to cut down gaseous emissions from combustion sources - vehicles and industry, says Roychowdhury.
She suggests that it is important to keep emissions from vehicles low and phase in electric mobility as well as aggressively control industrial emissions. There is also a need tomassively scale up convenient, affordable and reliable public transport systems. Also, more ofpedestrian and cycling-friendly compact and accessible mobility plans can be initiated.