Gurgaon: Haryana is emerging as a significant ozone hotspot in India, with ground-level ozone becoming a growing air quality concern even as particulate pollution remained relatively subdued during May. Data from the Central Pollution Control Board's (CPCB) continuous ambient air quality monitoring network reveals that 12 of the state's 30 monitoring stations breached national standards for ozone during the month. Nathu Colony in Ballabhgarh recorded the seventh-highest ground-level ozone concentration in India in May.
National Ozone Standards Breached
According to CPCB data, 40% of Haryana's monitoring stations reported at least one day when the maximum rolling eight-hour ozone concentration exceeded the National Ambient Air Quality Standard (NAAQS) of 100 micrograms per cubic metre (µg/m3). Nationally, analysis by the Centre for Research on Energy and Clean Air (CREA) indicates that while winter air quality management remains focused on particulate matter, Haryana may increasingly need to address ozone pollution during the summer months.
Regional Air Quality Challenge
Unlike particulate pollution, which is often concentrated near emission sources, ozone can travel long distances and affect areas far from where its precursor pollutants are emitted. This makes ozone a regional air quality challenge that requires coordinated action across sectors and districts. The findings underscore the rise of a pollutant that is increasingly becoming a summer air quality issue across the state, even as particulate pollution levels ease after winter.
Nathu Colony, Ballabhgarh
The national analysis by CREA found that Nathu Colony in Ballabhgarh registered a maximum eight-hour average ozone concentration of 278 µg/m3, nearly three times the national standard. The highest ozone concentration in the country was recorded at Manali village in Chennai (500 µg/m3), followed by MIET College in Meerut (425 µg/m3), Manali in Chennai (361 µg/m3), Buddha Colony in Muzaffarpur (306 µg/m3), Pusa in Delhi (292 µg/m3), and Hakimapada in Angul, Odisha (292 µg/m3). Ballabhgarh ranked seventh nationally, ahead of stations in Moradabad, Tonk, and Sri Ganganagar.
Health and Environmental Impacts
Health experts warn that exposure to elevated ozone concentrations can irritate airways, reduce lung function, worsen asthma and other respiratory illnesses, and increase hospital visits among vulnerable populations. The pollutant can also damage crops and natural vegetation.
Top Ozone Hotspots in Haryana in May
- F-Block in Sirsa recorded the highest number of exceedance days, with ozone levels crossing the prescribed limit on 13 days during May.
- Amity University in Panchgaon followed with 11 exceedance days.
- Shyam Nagar in Palwal and Urban Estate-II in Hisar recorded six exceedance days each.
- The NISE monitoring station at Gwal Pahari in Gurgaon reported four days above the standard.
Analyst at CREA Manoj Kumar told TOI, "The distribution of ozone hotspots across Haryana reflects the secondary nature of ozone pollution. Ozone is formed through sunlight-driven reactions between NOx and VOCs, and its concentrations are strongly influenced by atmospheric transport and photochemical processes, often leading to peak levels away from the original emission sources."
