Influence and distribution pattern of n-Alkanes in PM2.5 and PM10 during odd- even scheme in Delhi, India

To comprehend and enhance Delhi's air quality, the state government implemented an odd-even scheme during 4-15 November 2019, aimed at reducing on-road traffic. The average mass concentrations of PM2.5 and PM10 at CSIR-NPL were observed as 250.6 +/- 48.7 mu g/m3 and 345.3 +/- 54.6 mu g/m3, respectively. The organic species, i.e., n-alkanes were also determined in PM2.5 and PM10 at CSIR-NPL. The average concentrations of total n-alkanes were 1387.4 +/- 94.8 ng/m3 and 1555.0 +/- 145.1 ng/m3 in PM2.5 and PM10, respectively, during this period at CSIR-NPL. The Carbon Preference Index (CPI) values for PM2.5 and PM10 at CSIR-NPL were 1.66 and 1.37, respectively, indicating mixed emissions arising from both anthropogenic and biogenic sources at this studied location. The concentration-weighted trajectory (CWT) showed the influence of the mass abundance of pollutants in Delhi from the Punjab and Haryana regions.