Volatile organic compounds (VOCs) are important precursors of ozone and fine particulate matter, and have attracted more and more research attention. There are few long-term observational studies of VOCs in automobile industry parks. From January 1 to December 31,2019, 79 kinds of VOCs were quantitatively detected by on-line gas chromatograph in an automobile industrial park in Shanghai. The composition, seasonal variation, and daily variation of VOCs were analyzed. The chemical reactivity of the atmosphere was estimated using the maximum incremental reactivity (MIR) and·OH radical loss rate. The sources of VOCs were analyzed using specific pollutant ratios and factor analysis. The results showed that the total VOCs concentration was 26.53×10-9, with alkanes, alkenes, aromatics, halo hydrocarbon, and alkynes accounting for 50.2%, 9.8%, 22.4%, 10.8%, and 6.8%, respectively. There was an obviously seasonal variation in VOCs concentrations, with the maximum occurring in winter and the minimum in summer. Ozone formation potential (OFP) was 73.2×10-9, of which alkanes accounted for 14.7%, alkenes 35.9%, and aromatics 45.2%. The·OH radical loss rate was 165.3 s-1, of which alkenes accounted for 30.4% and aromatics 48.9%. The components with the highest contributions to chemical reaction activity were m/p-xylene, ethylene, propylene, toluene, and o-xylene. By estimating toluene/benzene ratios (T/B) and ethane/acetylene ratios (E/E), the air mass at the observation site was fresh, site was close to the pollution source. The main sources of VOCs were gasoline exhaust emissions (19.4%), solvent use (30.8%), combustion processes (11.0%), diesel use (8.9%), and liquefied petroleum gas use (4.5%).
Keywords: automobile industrial park; chemical reactivity; ozone formation potential (OFP); source apportionment; volatile organic compounds (VOCs); ·OH radical loss rate (L·OH).