Pollution Characteristics and Source Apportionment of Volatile Organic Compounds (VOCs) in Qinhuangdao City during Autumn and Winter
Continuous monitoring of 114 volatile organic compounds (VOCs) was conducted in the urban atmosphere of Haigang District, Qinhuangdao City, from September 2022 to February 2023. The volume concentrations of total VOCs were 42.72×10⁻⁹ in autumn and 25.15×10⁻⁹ in winter. The predominant species were isopentane, ethane, and ethylene. Ozone formation potential (OFP) analysis indicated that alkanes and alkenes dominated the atmospheric pollution during autumn and winter, with isopentane and ethylene being the largest contributors. Aromatic hydrocarbons contributed up to 85.00% of the secondary organic aerosol formation potential (SOAFP), with benzene as the primary species. Positive matrix factorization (PMF) identified four major sources: technological processes and oil/gas volatilization (35.57%), combustion and petrochemical emissions, motor vehicle emissions, and regional background sources. The results underscore the need for targeted control of VOCs from industrial and vehicular sources to mitigate secondary pollution in coastal cities.