Article’s

Delhi experiences chronic and extreme air pollution driven by a complex mixture of primary and secondary atmospheric pollutants, posing substantial environmental and public health risks. This study provides a comprehensive assessment of the impacts of chlorofluorocarbons (CFCs) in conjunction with major criteria pollutants-fine and coarse particulate matter (PM and PM10), nitrogen oxides (NOx), sulphur dioxide (SO₂), and troposphere ozone (0₂) on urban air quality and population health in Delhi. Longitudinal air quality and exposure data were obtained from the Central Pollution Control Board (CPCB) and international datasets and were analyzed to evaluate temporal variability, seasonal exceed and compliance with national and World Health Organization (WHO) guidelines. While direct CFC emissions have declined following regulatory controls, their long atmospheric residence time continues to influence stratospheric ozone depletion, indirectly enhancing surface-level ultraviolet radiation exposure and associated health risks. Epidemiological evidence suggests a strong association between elevated pollutant concentrations and increased incidence of respiratory and cardiovascular morbidity, particularly among susceptible subpopulations. Annual mean PM.s concentrations in Delhi ranged between approximately 90-110 µg m, exceeding the WHO guideline value of 5 µg m³ by more than 18-22 times. Peak winter concentrations frequently surpassed 250 µg m³. PM2.5 consists of extremely fine particles that can penetrate deep into the respiratory tract, enter the bloodstream, damage blood vessels, and impair lung function.