DECIPHERING URBAN AIR QUALITY THROUGH MULTI-POLLUTANT ASSESSMENT
DOI:
https://doi.org/10.69980/zb1d2y80Keywords:
urban air quality, multi-pollutant assessment, particulate matter, Air Quality Index, seasonal variation, Indian citiesAbstract
The increasing urbanisation, traffic, industrial activities, construction and energy usage has further exacerbated air quality issues in urban areas of India. The study adopted a quantitative, observational and longitudinal approach to assess the multi-pollutant pattern in Delhi, Mumbai, Kolkata, Chennai and Bengaluru from 2015 to 2024. The concentrations of PM₂.₅, PM₁₀, NO₂, SO₂, CO and ground-level O3 were analysed in conjunction with Air Quality Index categories. Spatial and temporal variations were interpreted using descriptive statistics, city-wise comparison, annual and seasonal assessment, correlation analysis and principal component analysis. The findings showed that PM being the most predominant pollution concern in the urban environment, the pollution burden in Delhi was the highest, while the levels of particulate matter were comparatively lower in the cities of Chennai and Bengaluru. Strong association with PM₁₀ and moderate correlation with NO₂ and CO indicated the common effect of traffic and other sources of combustion, dust, and construction activities on PM₂.₅. The particulate accumulation was the highest in winter and post-monsoon season while monsoon had lowest particulates. Overall, there was a decreasing trend in annual AQI values; however, in certain cities improvement was uneven, and unhealthy conditions were observed for significant periods of the assessment period. To achieve this, comprehensive traffic and road and construction dust, industrial combustion, municipal waste burning, household fuel consumption emission control is required. The multi-pollutant assessment provides a better foundation for air-quality management, exposure reduction, public-health protection and long-term urban environmental planning on a city-by-city basis.
References
1.Biswal, A., Singh, T., Singh, V., Ravindra, K., & Mor, S. (2020). COVID-19 lockdown and its impact on tropospheric NO₂ concentrations over India using satellite-based data. Heliyon, 6(9), Article e04764. https://doi.org/10.1016/j.heliyon.2020.e04764
2.Chatterjee, D., McDuffie, E. E., Smith, S. J., Bindle, L., van Donkelaar, A., Hammer, M. S., Venkataraman, C., Brauer, M., & Martin, R. V. (2023). Source contributions to fine particulate matter and attributable mortality in India and the surrounding region. Environmental Science & Technology, 57(28), 10263–10275. https://doi.org/10.1021/acs.est.2c07641
3.Chowdhury, S., Dey, S., Guttikunda, S., Pillarisetti, A., Smith, K. R., & Di Girolamo, L. (2019). Indian annual ambient air quality standard is achievable by completely mitigating emissions from household sources. Proceedings of the National Academy of Sciences of the United States of America, 116(22), 10711–10716. https://doi.org/10.1073/pnas.1900888116
4.de Bont, J., Krishna, B., Stafoggia, M., Banerjee, T., Dholakia, H., Garg, A., Ingole, V., Jaganathan, S., Kloog, I., Lane, K. J., Mall, R. K., Mandal, S., Nori-Sarma, A., Prabhakaran, D., Rajiva, A., Tiwari, A. S., Wei, Y., Wellenius, G. A., Schwartz, J., . . . Ljungman, P. (2024). Ambient air pollution and daily mortality in ten cities of India: A causal modelling study. The Lancet Planetary Health, 8(7), e433–e440. https://doi.org/10.1016/S2542-5196(24)00114-1
5.Fuller, R., Landrigan, P. J., Balakrishnan, K., Bathan, G., Bose-O’Reilly, S., Brauer, M., Caravanos, J., Chiles, T., Cohen, A., Corra, L., Cropper, M., Ferraro, G., Hanna, J., Hanrahan, D., Hu, H., Hunter, D., Janata, G., Kupka, R., Lanphear, B., . . . Yan, C. (2022). Pollution and health: A progress update. The Lancet Planetary Health, 6(6), e535–e547. https://doi.org/10.1016/S2542-5196(22)00090-0
6.Health Effects Institute. (2024). State of global air 2024. https://www.stateofglobalair.org/resources/archived/state-global-air-report-2024
7.India State-Level Disease Burden Initiative Air Pollution Collaborators. (2019). The impact of air pollution on deaths, disease burden, and life expectancy across the states of India: The Global Burden of Disease Study 2017. The Lancet Planetary Health, 3(1), e26–e39. https://doi.org/10.1016/S2542-5196(18)30261-4
8.India State-Level Disease Burden Initiative Air Pollution Collaborators. (2021). Health and economic impact of air pollution in the states of India: The Global Burden of Disease Study 2019. The Lancet Planetary Health, 5(1), e25–e38. https://doi.org/10.1016/S2542-5196(20)30298-9
9.Jaganathan, S., Rajiva, A., Amini, H., de Bont, J., Dixit, S., Dutta, A., Kloog, I., Lane, K. J., Menon, J. S., Nori-Sarma, A., Prabhakaran, D., Schwartz, J. D., Sharma, P., Stafoggia, M., Walia, G. K. K., Wellenius, G., Prabhakaran, P., Ljungman, P., & Mandal, S. (2025). Nationwide analysis of air pollution hotspots across India: A spatiotemporal PM₂.₅ trend analysis (2008–2019). Environmental Research, 264, Article 120276. https://doi.org/10.1016/j.envres.2024.120276
10.Kawano, A., Kelp, M., Qiu, M., Singh, K., Chaturvedi, E., Dahiya, S., Azevedo, I. L., & Burke, M. (2025). Improved daily PM₂.₅ estimates in India reveal inequalities in recent enhancement of air quality. Science Advances, 11(4), Article eadq1071. https://doi.org/10.1126/sciadv.adq1071
11.Mahato, S., Pal, S., & Ghosh, K. G. (2020). Effect of lockdown amid COVID-19 pandemic on air quality of the megacity Delhi, India. Science of the Total Environment, 730, Article 139086. https://doi.org/10.1016/j.scitotenv.2020.139086
12.Manisalidis, I., Stavropoulou, E., Stavropoulos, A., & Bezirtzoglou, E. (2020). Environmental and health impacts of air pollution: A review. Frontiers in Public Health, 8, Article 14. https://doi.org/10.3389/fpubh.2020.00014
13.Markandeya, Verma, P. K., Mishra, V., Singh, N. K., Shukla, S. P., & Mohan, D. (2021). Spatio-temporal assessment of ambient air quality, their health effects and improvement during COVID-19 lockdown in one of the most polluted cities of India. Environmental Science and Pollution Research, 28, 10536–10551. https://doi.org/10.1007/s11356-020-11248-3
14.Ministry of Environment, Forest and Climate Change. (2019). National clean air programme. Government of India. https://www.neeri.res.in/file_homes/National%20Clean%20Air%20Program.pdf
15.Naqvi, H. R., Datta, M., Mutreja, G., Siddiqui, M. A., Naqvi, D. F., & Naqvi, A. R. (2021). Improved air quality and associated mortalities in India under COVID-19 lockdown. Environmental Pollution, 268, Article 115691. https://doi.org/10.1016/j.envpol.2020.115691
16.Ravindra, K., Singh, T., Biswal, A., Singh, V., & Mor, S. (2021). Impact of COVID-19 lockdown on ambient air quality in megacities of India and implication for air pollution control strategies. Environmental Science and Pollution Research, 28, 21621–21632. https://doi.org/10.1007/s11356-020-11808-7
17.Ravishankara, A. R., David, L. M., Pierce, J. R., & Venkataraman, C. (2020). Outdoor air pollution in India is not only an urban problem. Proceedings of the National Academy of Sciences of the United States of America, 117(46), 28640–28644. https://doi.org/10.1073/pnas.2007236117
18.Schraufnagel, D. E., Balmes, J. R., Cowl, C. T., De Matteis, S., Jung, S.-H., Mortimer, K., Perez-Padilla, R., Rice, M. B., Riojas-Rodriguez, H., Sood, A., Thurston, G. D., To, T., Vanker, A., & Wuebbles, D. J. (2019a). Air pollution and noncommunicable diseases: A review by the Forum of International Respiratory Societies’ Environmental Committee, Part 1: The damaging effects of air pollution. Chest, 155(2), 409–416. https://doi.org/10.1016/j.chest.2018.10.042
19.Schraufnagel, D. E., Balmes, J. R., Cowl, C. T., De Matteis, S., Jung, S.-H., Mortimer, K., Perez-Padilla, R., Rice, M. B., Riojas-Rodriguez, H., Sood, A., Thurston, G. D., To, T., Vanker, A., & Wuebbles, D. J. (2019b). Air pollution and noncommunicable diseases: A review by the Forum of International Respiratory Societies’ Environmental Committee, Part 2: Air pollution and organ systems. Chest, 155(2), 417–426. https://doi.org/10.1016/j.chest.2018.10.041
20.Shaddick, G., Salter, J. M., Peuch, V.-H., Ruggeri, G., Thomas, M. L., Mudu, P., Tarasova, O., Baklanov, A., & Gumy, S. (2021). Global air quality: An inter-disciplinary approach to exposure assessment for burden of disease analyses. Atmosphere, 12(1), Article 48. https://doi.org/10.3390/atmos12010048
21.Sharma, S., Zhang, M., Anshika, Gao, J., Zhang, H., & Kota, S. H. (2020). Effect of restricted emissions during COVID-19 on air quality in India. Science of the Total Environment, 728, Article 138878. https://doi.org/10.1016/j.scitotenv.2020.138878
22.Southerland, V. A., Brauer, M., Mohegh, A., Hammer, M. S., van Donkelaar, A., Martin, R. V., Apte, J. S., & Anenberg, S. C. (2022). Global urban temporal trends in fine particulate matter (PM₂.₅) and attributable health burdens: Estimates from global datasets. The Lancet Planetary Health, 6(2), e139–e146. https://doi.org/10.1016/S2542-5196(21)00350-8
23.United Nations Environment Programme. (2021). Actions on air quality: A global summary of policies and programmes to reduce air pollution. https://www.unep.org/resources/report/actions-air-quality-global-summary-policies-and-programmes-reduce-air-pollution
24.Vohra, K., Vodonos, A., Schwartz, J., Marais, E. A., Sulprizio, M. P., & Mickley, L. J. (2021). Global mortality from outdoor fine particle pollution generated by fossil fuel combustion: Results from GEOS-Chem. Environmental Research, 195, Article 110754. https://doi.org/10.1016/j.envres.2021.110754
25.World Health Organization. (2021). WHO global air quality guidelines: Particulate matter (PM₂.₅ and PM₁₀), ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide. https://www.who.int/publications/i/item/9789240034228
