The preconcentration/gas chromatography-mass spectrometry with FID detector method was used to observe the 115 atmospheric volatile organic compounds (VOCs) of Tai’an urban area in autumn 2020. The average volume fraction of VOCs during the observation period was (67.50±25.55)×10⁻⁹, dominated by alkanes (34.86%) and oxygenated volatile organic compounds (OVOCs) (32.03%). The atmospheric chemistry reactivity of VOCs was estimated using ozone formation potential (OFP) and the OH radical loss rate (L_OH), respectively. The OFP of Tai’an in autumn was (241.50±6.91)×10⁻⁹, mainly contributed by OVOCs (39.92%) and aromatics (33.03%). The calculated L_OH was 7.34±0.33 s⁻¹, which was dominated by OVOCs (56.32%). The contribution of VOCs to the potential for secondary organic aerosol (SOA) formation was estimated using the fractional aerosol coefficients (FAC), and the results showed that SOA formation potential was (366.58±37.80)×10⁻⁹, dominated by aromatics (98.79%). The results of the characteristic species ratio analysis showed that the VOCs of Tai’an in autumn were influenced by local sources such as traffic-related emissions, solvent use and combustion sources. The source apportionment results showed that the contribution of motor vehicle emissions to VOCs was the highest at 26.1%, with the contributions from gasoline vehicle exhaust emissions and diesel vehicle exhaust emissions being 19.4% and 6.7%. The contribution of solvent use and industrial sources to VOCs was comparable at 20.1% and 19.9%, respectively. The contribution of stationary combustion sources and liquefied petroleum gas (LPG) use was 16.2% and 12.3%, respectively. Biogenic sources contributed the lowest percentage of 5.4%.

volatile organic compounds (VOCs), reaction activity, secondary organic aerosol (SOA), characteristic species ratio, source apportionment