Source apportionment of volatile organic compounds: Implications to reactivity, ozone formation, and secondary organic aerosol potential

Abstract

Volatile organic compounds (VOCs) are important contributors to atmospheric chemical reactivity rate (LOH), ozone formation potential (OFP), and secondary organic aerosol formation potential (SOAP). The purpose of this study was to determine the contributions of different VOC sources to LOH, OFP, and SOAP using positive matrix factorization (PMF) model. Hourly observation of ambient VOCs at a megacity of Central China was conducted for one month in winter. The LOH, OFP, and SOAP of VOC species were firstly estimated. The PMF model was then used to apportion their sources. Five VOC sources including solvent usage, gasoline evaporation, combustion sources, vehicle emissions, and industrial sources were apportioned with their average contributions of 11.6%, 14.2%, 39.0%, 22.5%, and 12.6%, respectively. Industrial sources were the highest contributors to the LOH and SOAP with average contributions of 32.2% and 32.8%, respectively, while vehicle emissions contributed most to the OFP (27.8%). This study highlighted that the VOCs and ozone pollution control should give priority to the reactivity (OFP and SOAP) based strategies rather than concentration contribution-based strategies.