[Source Apportionment and Pollution Characteristics of VOCs in Suqian Based on Industrial Source Spectrum]

To characterize the volatile organic compounds （VOCs） and ozone （O₃） pollution in Suqian and quantitatively evaluate the contribution from industrial emissions， online measurements of 116 types of VOCs were carried out in Suqian in the summer of 2023 together with offline samples collected in a typical industrial area. Combined with other measurements and receptor models， the mass variations of VOCs， source apportionment， and O₃ pollution were investigated. The φ（TOVCs） during the monitoring period was 21.78×10^-9. The oxygen-containing VOC and alkane showed the highest contribution to the TVOCs. The total ozone formation potential （OFP） reached 109.67 μg·m^-3， with the highest contribution from acetaldehyde， toluene， and isoprene. Positive matrix factorization （PMF） agreed well with the ME-2 model based on measured industrial sources. However， the contribution of industrial sources to the TVOCs and the proportion of oxygen-containing VOCs resolved by PMF were relatively higher， indicating that fresh VOCs from the industrial sources were easy to age and increase while emitted into the atmosphere. During O₃ pollution days， industrial， transportation， and biological sources increased. Secondary sources exhibited the highest increase （51.7%） with their contribution to TVOCs up to 36.1% from 30.4% during non-polluted days. During the study period， both O₃ and PM_2.5 showed strong correlations with TVOCs. The mass concentrations of PM_2.5， especially the secondary components， increased significantly in O₃-polluted days， with secondary organic aerosols increasing the most （42.9%）. The results highlight the significant contributions of elevated VOC emissions to O₃ and PM_2.5 pollution driven by favorable meteorology conditions and its important role in the formation of atmospheric secondary processes.