Research on Organic Carbon and Elemental Carbon Distribution Characteristics and Their Influence on Fine Particulate Matter (PM2.5) in Changchun City

In order to understand the distribution characteristics of organic carbon (OC) and elemental carbon (EC) in PM2.5 in Changchun; China; PM2.5 samples were collected from April 2017 to December 2017 using the KC-120H particulate matter sampler; and the NIOSH 5040 method was used for determination. The results showed that the average concentration of PM2.5 in Changchun was 45.92 µg/m3 (45.92 ± 50.17), and the annual average concentrations of OC and EC ranged from 15.69 to 24.32 µg/m3 and from 1.38 to 2.33 µg/m3; respectively. The annual OC/EC ratio range was 8.08–15.44; with an average of 11.70. OC and EC concentrations in spring were the lowest; whereas higher levels of both OC and EC were found in winter. Significant correlations between OC and EC were found in the non-heating period; indicating that there was a consistent or similar source; whereas OC was non-significantly correlated with EC in the heating period; suggesting that contributions of OC were from unrelated combustion sources.