Characteristics and Priority Control Species of Ambient VOCs in a Coal-Coking Industrial Park in the Fenwei Plain.

Abstract

Industrial parks are important sources of volatile organic compounds (VOCs), which contribute to the formation of ozone (O3) and fine particulate matter (PM2.5) and pose inhalation health risks. However, control strategies focusing only on concentration or photochemical reactivity seldom achieve simultaneous benefits for air quality and human health. This study conducted four seasonal field campaigns from 08:00 to 20:00 in the core production zone of a coal-coking industrial park on the Fenwei Plain, China. An entropy-weighted Comprehensive Priority Index (CPI) was developed to integrate atmospheric impacts and health risks. The mean total VOC (TVOC) concentration was 65.8 ± 40.2 ppbv, with the peak value recorded in winter (113 ± 41 ppbv). Alkanes (25.9%) and alkenes (23.2%) dominated the VOC mixture. TVOC concentrations were generally higher in the morning and lower in the afternoon during daytime sampling. Diagnostic ratios indicated year-round benzene dominance; seasonal B/T (benzene/toluene) ratios were 5.8, 6.3, 3.8 and 4.4, suggesting strong, continuous influence from coking-related emissions. During summer and autumn, the mean ozone formation potential (OFP) values were 420 and 330 μg/m3, respectively, mainly driven by low-carbon alkenes. During spring and winter, aromatic hydrocarbons dominated secondary organic aerosol formation potential (SOAP). Acrolein was the primary contributor to total non-carcinogenic risk, while benzene was the major contributor to carcinogenic risk and the largest acute risk contributor. Cross-scenario CPI analysis identified benzene, acrolein, toluene, m-/p-xylene, 1,3-butadiene, and 1,2-dichloroethane as common priority species. These findings support integrated VOC control strategies for coal-coking industrial parks to simultaneously improve air quality and protect human health.