Source Apportionment, Environmental Impact and Health Risk Assessment of Volatile Organic Compounds in Dezhou, North China

Comprehensive Characterization of Ambient Volatile Organic Compounds (VOCs) in Two Industrial Parks and Clusters of Tianjin: Environmental Behaviors, Source Apportionment, and Health Risk Assessment

To reveal the chemical composition and concentration distribution, spatial distribution characteristics, source composition, and health impacts of volatile organic compounds (VOCs) in the two multi-industry industrial parks in Tianjin, 57 VOC species were determined by using SUMMA canister sampling with preconcentration gas chromatography/mass spectrometry. Based on these measurements, the Positive Matrix Factorization (PMF) model was used for source analysis to achieve quantitative identification and contribution analysis of different source factors. The health risks of VOC concentrations were analyzed based on the assessment framework recommended by the United States Environmental Protection Agency (USEPA). The results showed that the average concentrations of TVOCs in A-1 (Industrial Park and Cluster A, 5 m), A-2 (Industrial Park and Cluster A, 10 m), B-1 (Industrial Park and Cluster B, 5 m), and B-2 (Industrial Park and Cluster B, 10 m) were 59.72 ppbv, 45.35 ppbv, 32.44 ppbv, and 21.65 ppbv, respectively. TVOC concentrations were higher at A-1 and B-1 than at A-2 and B-2, and were generally higher at site A than at site B. The VOC components were mainly alkanes (53.5%–71.4%), followed by aromatic hydrocarbons (15.6%–36.2%), alkenes (4.6%–9.9%), and alkynes (3.1%–7.6%). The proportion of aromatic hydrocarbons in A was higher (22.13% and 36.22%), while alkanes dominated absolutely in B (71.4% and 66.9%). n-Hexane was the key species driving the spatial differences (a typical source of VOCs in solvent usage). The concentration in A-1 was 3.1 times that of A-2, and B-1 was 3.3 times that of B-2. It was mainly controlled by local solvent unorganized emissions. The differences in species between the two points at site A for toluene, xylene, etc., were relatively gentle, while at site B, the concentration of the same aromatic hydrocarbons at B-1 was significantly higher than that at B-2, presenting a clearer spatial characteristic, indicating differences in the spatial distribution of organic solvent-related industrial activities in different sites. The source analysis showed that A-1 was dominated by solvent usage (38.64%) and natural gas/LPG sources (36.96%); A-2 by vehicle exhaust (40.20%) and natural gas/LPG sources (36.15%); B-1 by cleaning-agent usage (38.81%) and fuel combustion (30.33%); and B-2 by plastic and rubber production (36.90%) and fuel combustion (31.84%). The health risk assessment showed that benzene, n-hexane, and xylene dominated the non-carcinogenic risks, but the overall non-carcinogenic (HI < 1) and carcinogenic (CR < 1 × 10−6) risks were both below the threshold. This study reveals inter-site differences in VOC concentrations, compositions, and source contributions across two mixed industrial parks, providing a basis for site-specific VOC control priorities, source-targeted monitoring strategies, and risk management in mixed industrial areas.

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

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.

Selection of Priority VOC Emission Sources in Seoul by Comparing Source Contributions and Health Risk-Based Contributions

This study conducted age-specific and source-oriented health risk assessments of volatile organic compounds (VOCs) at four measurement sites in Seoul (Gangseo (GS), Gwangjin (GJ), Bukhansan (BHS), and Jongno (JN)). By comparing source-specific concentration contributions with health risk-based contributions, priority sources and compounds were identified. The age-specific health risk assessment showed that, under the central tendency exposure (CTE) scenario, both the total excess cancer risk (TECR) and hazard index (HI) at all measurement sites remained below the recommended guideline values. However, under the reasonable maximum exposure (RME) scenario, TECR exceeded 1 × 10−6 for some adult and elderly groups, indicating the potential for adverse health effects. Compound-specific analysis identified Benzene and Ethylbenzene as the major contributors to TECR, whereas Ethylbenzene, Benzene, and Toluene were the primary contributors to HI. The source-oriented health risk assessment revealed that concentration-based and health risk-based source contributions exhibited different patterns, with manufacturing-related sources ranking among the highest contributors to health risks at all measurement sites. At the GS site, the highest-ranking sources in terms of concentration and health risk contributions were Metal processing product manufacturing and Other product manufacturing, respectively. At the GJ site, Fuel-related emissions ranked highest in concentration contribution, whereas Metal processing products, chemicals and chemical products manufacturing ranked highest in health risk contribution. At the BHS and JN sites, Background hydrocarbons showed the greatest concentration contribution, while Chemicals and chemical products manufacturing, Vehicle exhaust: Acetylene-rich, and Textile product manufacturing were the major contributors. This study demonstrates that VOC management in Seoul should prioritize health risk-based rather than concentration-based approaches.

Distribution, source and ecological risk assessment of polycyclic aromatic hydrocarbons in cultivated land of Liuxin area, Xuzhou, China

The spatial distribution, sources and ecological risk of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) in surface soil from Liuxin area, Xuzhou, China was investigated in this study. Gas chromatography-mass spectrometry analysis revealed ΣPAH concentrations ranging from 115.66 to 373.53 ng ⋅g−1 (mean: 196.26 ng ⋅ g−1), with phenanthrene (Phe) exhibiting the highest mean concentration (51.18 ng ⋅ g−1). Spatial analysis demonstrated a southeast-to-northwest concentration gradient, with maximum PAH levels observed in southeastern zones. PAH composition showed dominance of low-molecular-weight species (2, 3 rings: 46.7%), followed by 5, 6 ring PAHs (28.3%), and 4-ring compounds (24.9%). Source apportionment using molecular diagnostic ratios and positive matrix factorization identified four primary contributors: coal-fired power generation & metallurgical emissions (34%), biomass combustion (31%), diesel fuel combustion/leakage (29%), traffic emissions (6%). Ecological risk assessment employing Dutch soil quality standards revealed localized exceedances in southeastern areas, particularly for fluoranthene (Fla) and Phe. However, toxic equivalency quotients remained low, with incremental lifetime cancer risks below 10−6 for all exposure pathways. These findings indicate that while PAH contamination warrants monitoring, current levels pose negligible carcinogenic risk to the local population.

Research progress on health risks and evaluation methods of multipollutant exposure to air pollutants in China

Assessment of ambient polycyclic aromatic hydrocarbons in Egbedi dumpsite in Osogbo, Nigeria

The open burning system of municipal solid waste (MSW) disposal releases varying concentrations of emissions into the atmosphere. One of such, Polycyclic Aromatic Hydrocarbons (PAHs) in the atmosphere have been documented to be a threat to humans. This study assessed the concentration of the ambient air PAHs in a MSW dumpsite at Egbedi, Osun State. A polyurethane foam (PUF) passive sampler was installed in 10 locations for 28 days to trap PAHs. The PAH results were subjected to a toxicity equivalence (TEQ), sources were identified by employing the existing diagnostic ratios, and inhalation dosage was investigated using the Excess Lifetime Cancer Risk Assessment (ELCR). The summation of the carcinogenic PAHs and the highest toxicity equivalence for rain and dry seasons were 0.241 µg/m3 and 0.369 µg/m3, and 0.070 and 0.110, respectively. The analysis revealed that the PAHs were mainly from the combustion of MSW. The ELCR values were (9.1 × 10–4) and (5.8 × 10–4), which were above the acceptable carcinogenic risk level of 1.0 × 10–6. The concentration of PAHs released is at a carcinogenic level and the TEQ and diagnostic ratio show that the emission source is from certain wastes. The PCA score plot showed a single cluster that was close to the center, indicating that the burning of MSW was the only source of emissions from the study location that added to the majority of the PAHs in the surrounding atmosphere. There is an urgent need to develop the dumpsite into a standard landfill.