Journal of Research in Environmental Health

Journal of Research in Environmental Health

Experimental Investigation of the Effects of Benzene and Toluene Emissions from Asaluyeh Petrochemical Units on Air Quality

Document Type : Research article

Authors
Omid Najmabadi 1
Nahid Hajeb 2
Sanaz Nouri 3
1 BSc Student, Department of HSE, Neyshabur Higher Education Center, University of Applied Science and Technology, Neyshabur, Iran.
2 MSc Student, Department of HSE, Kherad Institute of Higher Education, Bushehr, Iran.
3 M.Sc. in HSE (Health, Safety, and Environment), Safety Supervisor at Khorasan Steel, Professional Firefighting and Rescue Instructor.
10.22038/jreh.2026.98964.1762
Abstract
Background and Objective: Atmospheric emissions of benzene, toluene, ethylbenzene, and xylene (BTEX) from petrochemical facilities pose critical environmental health concerns owing to the verified carcinogenicity of benzene (IARC Group 1) and the neurotoxic effects of other aromatics. This study aimed to investigate the ambient concentration, spatiotemporal distribution, dominant emission sources, and meteorological influences on BTEX compounds around a polystyrene petrochemical plant in the Pars Special Economic Energy Zone (Asaluyeh, Iran).

Materials and Methods: Active air sampling was conducted using activated charcoal sorbent tubes at a flow rate of 0.2 L/min across four fenceline stations (North, South, East, West). Sampling covered three seasons (Spring, Summer, and Autumn 2025; 24 daytime 8-hour samples in total). Chemical analysis was performed via gas chromatography with flame ionization detection (GC-FID) following NIOSH Method 1501 after carbon disulfide (CS_2) desorption. Statistical evaluations included one-way ANOVA, Tukey's HSD post-hoc test, and Pearson correlation analysis (α=0.05).

Results: The overall mean ∑▒BTEX concentration was 90.4 µg/m³. Ethylbenzene (51.22 µg/m³; 56.7%) and toluene (38.05 µg/m³; 42.1%) dominated the pollution profile, collectively accounting for ~98.8% of total emissions, whereas benzene constituted only 1.2% (1.10 µg/m³) and xylene remained below the detection limit (MDL<0.1 µg/m³). Spatial evaluation revealed the highest concentration at the South station (94.4 µg/m³) and the lowest at the North station (84.3 µg/m³), driven by prevailing wind dynamics. A significant seasonal decline occurred from Spring (119.8 µg/m³) to Summer (91.2 µg/m³) and Autumn (60.1 µg/m³). One-way ANOVA confirmed statistically significant seasonal variations for toluene (F(2,21)=7.79, p=0.003) and ethylbenzene (F(2,21)=18.59, p<0.001), but not for benzene (F(2,21) =2.72, p=0.089). A strong negative correlation was identified between total BTEX concentration and rainfall (r=-0.75, p<0.01), confirming atmospheric wet scavenging. The high toluene-to-benzene ratio (T/B=34.6) definitively identified industrial petrochemical processes, rather than vehicular exhaust, as the primary pollution source.

Conclusion: Although mean benzene levels remained below the national ambient threshold (5 µg/m³), the absence of a WHO safe threshold for benzene, combined with substantial ethylbenzene and toluene loads, underscores the urgent need for fugitive emission abatement at the petrochemical source and continuous fenceline monitoring to safeguard surrounding communities.
Keywords
BTEX Compounds
Benzene
Toluene-To-Benzene Ratio
Industrial Air Pollution
Asaluyeh
GC-FID
1. World Health Organization (WHO). (2022). WHO global air quality guidelines: Particulate matter, ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide. World Health Organization. https://iris.who.int/handle/10665/345329
2. Mellouki, A., Wallington, T. J., & Chen, J. (2023). Atmospheric chemistry of volatile organic compounds: Reaction mechanisms and environmental impacts. Chemical Reviews, 123(9), 5678-5722. https://doi.org/10.1021/acs.chemrev.2c00812
3. Li, K., Jacob, D. J., Liao, H., Shen, L., Zhang, Q., & Bates, K. H. (2022). A two-pollutant strategy for ozone pollution control in China through VOCs and NOx reduction. Nature Geoscience, 15(3), 192-198. https://doi.org/10.1038/s41561-021-00878-3
4. Afrasiabi, S., Fattahi Darghlou, M., Mohammadi, Y., & Leili, M. (2024). Effects of short and long-term exposure to benzene, toluene, ethylbenzene, and xylenes (BTEX) in indoor environment air on human health: A systematic review and meta-analysis. Journal of Air Pollution and Health, 9(4), 551-566.  https://doi.org/10.18502/japh.v9i4.17653
5. Pandis, S. N., & Seinfeld, J. H. (2024). Atmospheric Chemistry and Physics: From Air Pollution to Climate Change (4th ed.). John Wiley & Sons, New Jersey. ISBN: 978-1-119-72218-1. https://doi.org/10.5194/egusphere-2024-1317-AC2
6. Orlando, J. J., & Tyndall, G. S. (2023). Gas-phase atmospheric oxidation mechanism of volatile organic compounds. Accounts of Chemical Research, 56(4), 412-421. https://doi.org/10.1021/acs.accounts.2c00715
7. International Agency for Research on Cancer (IARC). (2023). Benzene and other aromatic hydrocarbons: Updated evaluation of carcinogenic risks to humans (IARC Monographs Volume 128). World Health Organization, Lyon, France.
8. Zarei-chargoud, A., Faghihi-Zarandi, A., & Faraji, M. (2025). Analysis of BTEX in ambient air using gas chromatography-flame ionization detector to assess health risks. Analytical Methods in Environmental Chemistry Journal, 8(1), 133-151.  https://doi.org/10.24200/amecj.v8.i01.1028
9. Alenezi, A., Al-Harbi, M., & Al-Mutairi, N. (2023). Spatiotemporal characterization and risk assessment of volatile organic compounds near industrial petroleum refining complexes. Environmental Monitoring and Assessment, 195(2), 312. https://doi.org/10.1007/s10661-022-10892-x
10. Geng, F., Zhang, X., & Wang, L. (2022). Industrial volatile organic compound emissions from petrochemical hotspots: A multi-year observation and source attribution review. Atmospheric Environment, 285, 119231. https://doi.org/10.1016/j.atmosenv.2022.119231
11. Goli, S., Mahvi, A. H., & Dehghani, M. (2023). Indoor and outdoor residential exposure to BTEX compounds in urban-industrial neighborhoods: Concentrations and risk evaluation. Environmental Science and Pollution Research, 30(11), 30412-30425. https://doi.org/10.1007/s11356-022-24210-9
12. Ghobakhloo, M., Dehghani, M., & Hoseini, M. (2024). Health risk assessment due to occupational and ambient exposure to BTEX compounds in industrial settings in Iran. Safety and Health at Work, 15(2), 180-189.  https://doi.org/10.1016/j.shaw.2024.01.004 PMid:39035807 PMCid:PMC11255933
13. Carter, W. P. L. (2023). Updated maximum incremental reactivity (MIR) scale for volatile organic compounds in atmospheric ozone formation. Atmospheric Environment, 298, 119610.  https://doi.org/10.1016/j.atmosenv.2023.119610
14. Bohn, B., & Fuchs, H. (2022.( OH radical reaction kinetics and atmospheric degradation mechanisms of benzene and alkylated benzenes. Physical Chemistry Chemical Physics, 24(18), 10892-10904. https://doi.org/10.1039/D2CP00412A
15. Wang, W., Chen, L., & Zhang, Y. (2022). Spatiotemporal variations, source profiles, and health risks of BTEX in a heavily industrialized coastal economic zone. Chemosphere, 291, 132890.  https://doi.org/10.1016/j.chemosphere.2021.132890 PMid:34801567
16. Guenther, A. B., & Jiang, X. (2023). Global emissions of biogenic volatile organic compounds: Interactions with anthropogenic pollutants in changing climates. Global Change Biology, 29(14), 3910-3926.  https://doi.org/10.1111/gcb.16712 PMid:37186484
17. Andreae, M. O. (2023). Emission of trace gases and aerosols from biomass burning and industrial combustion: An updated synthesis. Atmospheric Chemistry and Physics, 23(3), 1567-1602. https://doi.org/10.5194/acp-23-1567-2023
18. Zhao, Y., Yuan, Z., & Zheng, J. (2023). Speciated VOC emission profiles from petrochemical processing units: Source characterization and ozone creation potentials. Environmental Science & Technology, 57(12), 4812-4823. https://doi.org/10.1021/acs.est.2c08415
19. Sivacoumar, R., & Bhanarkar, A. D. (2022). Quantification and control of fugitive VOC emissions from petroleum refineries and petrochemical storage tanks. Journal of Environmental Management, 317, 115410 https://doi.org/10.1016/j.jenvman.2022.115410 PMid:35751247
20. Perez, L. C., & Tobias, A. (2022). Source apportionment of volatile organic compounds from vehicular exhaust and non-combustion traffic emissions. Science of The Total Environment, 838, 156312.  https://doi.org/10.1016/j.scitotenv.2022.156312 PMid:35636546
21. Wolkoff, P. (2022). Indoor air chemistry of volatile organic compounds: Sources, health implications, and mitigation strategies. Building and Environment, 219, 109210.  https://doi.org/10.1016/j.buildenv.2022.109210
22. Hecht, S. S., & Hatsukami, D. K. (2022). Volatile organic carcinogens in tobacco smoke and environmental air: Biomarkers of exposure and effect. Carcinogenesis, 43(8), 715-728.  https://doi.org/10.1093/carcin/bgac058 PMid:35749296 PMCid:PMC9486590
23. Liu, X., Song, C., & Zhang, Y. (2023). Measurement and emission factor development for benzene and aromatics in petrochemical processing facilities. Atmospheric Pollution Research, 14(5), 101740. https://doi.org/10.1016/j.apr.2023.101740
24. Kamarehie, B., Jafari, A. J., & Shahsavani, A. (2023). AERMOD dispersion modeling of BTEX emissions from a petrochemical complex: Human health risk assessment in surrounding communities. Environmental Research, 221, 115280.  https://doi.org/10.1016/j.envres.2023.115280 PMid:36657593
25. Derwent, R. G. (2022). Long-range atmospheric transport of volatile organic compounds and regional photochemical ozone creation. Atmospheric Environment, 270, 118880. https://doi.org/10.1016/j.atmosenv.2021.118880
26. Warneke, C., Coggon, M. M., & Gilman, J. B. (2023). Volatile organic compound lifetimes and chemical oxidation evolution in industrial plumes. Journal of Geophysical Research: Atmospheres, 128(6), e2022JD037890. https://doi.org/10.1029/2022JD037890
27. Burkholder, J. B., Sander, S. P., & Abbatt, J. P. D. (2022). Chemical kinetics and photochemical data for use in atmospheric studies: IUPAC and NASA evaluation update. Journal of Physical and Chemical Reference Data, 51(3), 033101.  https://doi.org/10.1063/5.0098120
28. Jenkin, M. E., Valorso, R., & Aumont, B. (2023). Development of Master Chemical Mechanism (MCM v3.3.1) updates for aromatic hydrocarbon degradation. Atmospheric Chemistry and Physics, 23(11), 6421-6440. https://doi.org/10.5194/acp-23-6421-2023
29. Sillman, S., & West, J. J. (2022). Non-linear photochemistry of ozone and secondary organic aerosol formation in industrial VOC-dominated atmospheres. Environmental Science & Technology, 56(8), 4890-4901. https://doi.org/10.1021/acs.est.1c07890
30. Ng, N. L., Zhang, R., & Claeys, M. (2023). Secondary organic aerosol formation mechanisms from aromatic volatile organic compounds: A review. Chemical Society Reviews, 52(15), 5120-5150. https://doi.org/10.1039/D2CS00891K
31. Zhang, Q., Jimenez, J. L., & Canagaratna, M. R. (2023). Global synthesis of secondary organic aerosol formation from industrial aromatic precursors. Accounts of Chemical Research, 56(10), 1180-1191.  https://doi.org/10.1021/acs.accounts.3c00045 PMid:37071750 PMCid:PMC10286310
32. Smith, M. T., Zhang, L., & McHale, C. M. (2022). Key characteristics of carcinogens applied to benzene-induced leukemogenesis: Mechanistic insights. Environmental Health Perspectives, 130(6), 065001. https://doi.org/10.1289/EHP10342
33. International Agency for Research on Cancer (IARC). (2022). Monographs on the identification of carcinogenic hazards to humans: Chemical agents and industrial exposures. IARC Scientific Publications, World Health Organization, Lyon.
34. Lan, Q., Rothman, N., & Zhang, L. (2023). Hematotoxicity and immunotoxicity in workers occupationally exposed to low levels of benzene. American Journal of Industrial Medicine, 66(4), 285-296.  https://doi.org/10.1002/ajim.23461 PMid:36719301
35. Schnatter, A. R., Glass, D. C., & Tang, X. (2022). Quantitative cancer risk assessment for occupational exposure to benzene: Meta-analysis of cohort studies. Risk Analysis, 42(9), 1980-1995.  https://doi.org/10.1111/risa.13880 PMid:35088440
36. Rana, I., & Dahal, S. (2023). Environmental fate, human exposure pathways, and health risk profiles of benzene in ambient atmospheres. Environmental Geochemistry and Health, 45(5), 2105-2122.  https://doi.org/10.1007/s10653-022-01410-w PMid:36459339
37. Montero-Montoya, R., & Lopez-Vargas, R. (2022). Combined toxicological effects and cumulative hazard quotients of BTEX component mixtures. Toxicology Letters, 365, 45-56.  https://doi.org/10.1016/j.toxlet.2022.06.002 PMid:35690225
38. Goudarzi, G., Hopke, P. K., & Yari, A. R. (2022). Health risk assessment of carcinogenic and non-carcinogenic exposure to BTEX compounds in industrial petroleum cities of Iran. Environmental Science and Pollution Research, 29(18), 27150-27162. https://doi.org/10.1007/s11356-021-17890-y
39. Hadei, M., Shahsavani, A., & Hopke, P. K. (2022). Microenvironmental concentrations and vertical gradients of volatile organic compounds in urban industrial environments. Sustainable Cities and Society, 78, 103620.  https://doi.org/10.1016/j.scs.2021.103620
40. United States Environmental Protection Agency (US EPA). (2023). Compendium Method TO-15A: Determination of volatile organic compounds (VOCs) in air collected in specially prepared canisters and analyzed by gas chromatography-mass spectrometry (GC-MS). EPA/600/R-23/112, Washington, D.C.
41. Zhang, J., Sun, Y., & Li, M. (2023). Recent technological advances in chromatographic sampling and GC-FID/GC-MS quantification of BTEX in air. Trends in Analytical Chemistry, 160, 116980.  https://doi.org/10.1016/j.trac.2023.116980 PMid:36818498 PMCid:PMC9922438
42. Fernandez-Iriarte, A., Santamaria, J. M., & Elustondo, D. (2023). Fenceline monitoring and spatial gradient analysis of BTEX compounds surrounding major industrial parks. Environmental Pollution, 320, 121080.  https://doi.org/10.1016/j.envpol.2023.121080 PMid:36702428
43. Liu, Y., Wang, T., & Song, M. (2022). Speciated volatile organic compounds and source fingerprinting near a mega-scale petrochemical complex. Science of The Total Environment, 812, 152430.  https://doi.org/10.1016/j.scitotenv.2021.152430 PMid:34952049
44. Li, Z., & Guo, J. (2023). Planetary boundary layer structure and atmospheric inversion impacts on VOC dispersion in industrial basins. Atmospheric Research, 282, 106512.  https://doi.org/10.1016/j.atmosres.2022.106512
45. Zallaghi, E., Babaei, A. A., & Goudarzi, G. (2022). Influence of meteorological parameters and seasonal scavenging on ambient BTEX levels in petroleum refining zones. Air Quality, Atmosphere & Health, 15(7), 1185-1198. https://doi.org/10.1007/s11869-022-01180-w
46. Naddafi, K., Hassanvand, M. S., & Yunesian, M. (2023). Long-term evaluation of BTEX concentrations and source identification in the urban atmosphere of Tehran, Iran. Urban Climate, 49, 101480.  https://doi.org/10.1016/j.uclim.2023.101480
47. Jafari, A. J., Kamarehie, B., & Ghaderpoori, M. (2022). Source apportionment and health risk assessment of volatile organic compounds in Tabriz industrial area. Ecotoxicology and Environmental Safety, 234, 113380.  https://doi.org/10.1016/j.ecoenv.2022.113380 PMid:35298964
48. Rad, H. D., Babaei, A. A., & Hoseini, M. (2022). Ambient concentrations and health risk analysis of BTEX compounds near petroleum industrial complexes in southern Iran. Chemosphere, 298, 134290.  https://doi.org/10.1016/j.chemosphere.2022.134290 PMid:35278446
49. Harrison, R. M. (2023). Air pollution: Sources, atmospheric transport, and global health consequences. Environmental Science: Processes & Impacts, 25(2), 140-158. https://doi.org/10.1039/D2EM00350A
50. Zhang, Y., Wang, L., & Zheng, M. (2022). Volatile organic compounds as precursors for secondary pollutants: Atmospheric mechanisms and control strategies. Atmospheric Environment, 276, 119020.  https://doi.org/10.1016/j.atmosenv.2022.119020
51. Hoek, G., & Brunekreef, B. (2022). Long-term air pollution exposure and health effects: Advances  https://doi.org/10.1183/13993003.01890-2021 PMid:34561282
52. Monks, P. S., & Williams, M. L. (2022). Fifty years of air quality management and atmospheric science: Historical milestones and future challenges. Environmental Science & Technology, 56(14), 9820-9835. https://doi.org/10.1021/acs.est.2c02110
53. Selech Petrochemical Industry Development Company. (2025). Annual Environmental and Production Technical Report. Asaluyeh, Iran. Official Corporate Document.
54. Pars Petrochemical Company. (2024). Feedstock Supply and Environmental Performance Report: Styrene Monomer & Aromatics Units. PSEEZ, Asaluyeh, Iran.
55. National Cartographic Center of Iran (NCC). (2024). Topographic and Spatial Geographic Database for Pars Special Economic Energy Zone (PSEEZ). Tehran, Iran.
56. Pars Special Economic Energy Zone Organization (PSEEZO). (2025). Infrastructure and Environmental Master Plan for Industrial Phase 2 Petrochemical Parks. Asaluyeh, Bushehr Province, Iran.
57. National Petrochemical Company of Iran (NPC). (2024). Petrochemical Industry Development Yearbook: Downstream Units and Capacity Profiles. Ministry of Petroleum, Tehran, Iran.
58. Iran Meteorological Organization (IRIMO). (2025). Synoptic Climatological Data and Wind Rose Analysis for Asaluyeh Weather Station (2020-2025). IRIMO Publications, Tehran.
59. Statistical Center of Iran (SCI). (2024). Demographic Estimates and Population Distribution in Asaluyeh County and Surrounding Residential Rural Settlements. Tehran, Iran.
60. Shahiki Tash, M. N., & Salarpour, M. (2023). Economic valuation of environmental air pollution damage from petrochemical industries in Pars Special Economic Zone. Journal of Environmental Studies, 49(2), 185-202. https://doi.org/10.22059/jes.2023.354120.1008390
61. Amini, H., & Mohammadi, A. (2023). A review of volatile organic compound pollution research in Asaluyeh petrochemical hub. Journal of Health and Environmental Research, 9(1), 15-28. https://doi.org/10.22034/jher.2023.15820
62. Department of Environment of Iran (DOE). (2023). Environmental Standards and Compliance Guidelines for Volatile Organic Compounds Emissions from Oil and Gas Refineries. DOE Press, Tehran, Iran.
63. Ahmadi, M., Jorfi, S., & Soltani, R. D. C. (2022). Multi-seasonal monitoring and spatial variation of BTEX compounds in an urban area heavily influenced by petrochemical operations. Environmental Pollution, 305, 119280.  https://doi.org/10.1016/j.envpol.2022.119280 PMid:35500712
64. Hazrati, S., Fazlzadeh, M., & Rastkari, N. (2023). Inhalation risk assessment of exposure to BTEX compounds in urban-industrial hotspot zones. Atmospheric Pollution Research, 14(2), 101650. https://doi.org/10.1016/j.apr.2022.101650
65. Wang, P., & Zhao, W. (2023). Speciated VOC emissions along industrial transportation corridors and roadside microenvironments. Transportation Research Part D: Transport and Environment, 115, 103580.  https://doi.org/10.1016/j.trd.2022.103580 PMid:36573137 PMCid:PMC9771761
66. National Institute for Occupational Safety and Health (NIOSH). (2022). Hydrocarbons, Aromatic: Method 1501 (Issue 3 Update). In NIOSH Manual of Analytical Methods (NMAM), 5th Edition. DHHS/CDC/NIOSH, Cincinnati, OH.
67. Krol, S., & Zabiegala, B. (2023). Advances in sorbent tube technology and active sampling protocols for ambient VOC analysis. Critical Reviews in Analytical Chemistry, 53(4), 812-830. https://doi.org/10.1080/10408347.2021.1989020
68. Ho, K. F., Cao, J. J., & Huang, R. J. (2022). Seasonal, day-night variations and chemical reactivity of atmospheric VOCs in coastal industrial zones. Science of The Total Environment, 825, 153920.  https://doi.org/10.1016/j.scitotenv.2022.153920 PMid:35189233
69. World Health Organization (WHO). (2022). Compendium of WHO guidance on health and environment: Air pollution guidelines for carcinogenic aromatics. World Health Organization, Geneva. License: CC BY-NC-SA 3.0 IGO.
70. National Institute for Occupational Safety and Health (NIOSH). (2023). NIOSH Manual of Analytical Methods (NMAM): Hydrocarbons, Aromatic (Method 1501). Centers for Disease Control and Prevention, Atlanta, GA.
71. Koziel, J. A., & Pawliszyn, J. (2022). Evolution of microextraction and solvent desorption methods for atmospheric VOC determination. Journal of Chromatography A, 1675, 463180.  https://doi.org/10.1016/j.chroma.2022.463180 PMid:35660314
72. Hsu, Y. C., Chen, C. Y., & Lin, C. W. (2023). Thermal desorption GC-MS characterization of fugitive BTEX emissions in petrochemical industrial estates. Atmospheric Pollution Research, 14(8), 101820. https://doi.org/10.1016/j.apr.2023.101820
73. European Committee for Standardization (CEN). (2022). EN 13528-2:2022 - Ambient air quality - Sorbent and diffusive samplers for the determination of concentrations of gases and vapours - Requirements and test methods. CEN, Brussels, Belgium.
74. Delik, A., & Koziel, J. A. (2023). Modern sampling and analytical strategies for volatile organic aromatics in complex industrial matrices. Advances in Environmental Analysis, 92, 145-172.  https://doi.org/10.1016/bs.coac.2023.02.001
75. Zhang, Y., Meng, F., & Chen, X. (2022). Spatiotemporal variation, source apportionment, and human cancer risk of ambient BTEX in densely populated industrial regions. Environmental Pollution, 308, 119680.  https://doi.org/10.1016/j.envpol.2022.119680 PMid:35787421
76. Cao, X., Wang, Y., & Liu, S. (2023). Spatiotemporal dynamics, photochemical reactivity, and health risks of BTEX in industrial coastal hubs. Chemosphere, 311, 137020.  https://doi.org/10.1016/j.chemosphere.2022.137020 PMid:36330974
77. Miller, L., & Wheeler, A. (2022). Multi-year evaluation of volatile aromatic hydrocarbons in industrial complex communities. Atmospheric Environment, 280, 119150. https://doi.org/10.1016/j.atmosenv.2022.119150
78. Hsu, Y. K., & Hopke, P. K. (2023). Advanced receptor modeling and directional source location of volatile organic compound emissions in complex industrial areas. Atmospheric Environment, 295, 119520.  https://doi.org/10.1016/j.atmosenv.2022.119520
79. Fazlzadeh, M., Hazrati, S., & Rostami, R. (2022). BTEX levels and health risk assessment in ambient air of residential settlements adjacent to industrial zones. Environmental Geochemistry and Health, 44(8), 2615-2628. https://doi.org/10.1007/s10653-021-01062-8
80. Delikhoon, M., Fazlzadeh, M., & Gholampour, A. (2023). Seasonal variation and inhalation health risk of BTEX compounds in Tabriz industrial area. Air Quality, Atmosphere & Health, 16(3), 521-534. https://doi.org/10.1007/s11869-022-01288-z
81. Van Langenhove, H., & Walgraeve, C. (2022). Long-term monitoring trends of aromatic hydrocarbons in European petrochemical port zones. Environmental Science and Pollution Research, 29(35), 53120-53132. https://doi.org/10.1007/s11356-022-20150-x
82. Santamaria, J. M., Elustondo, D., & Bermejo, R. (2022). Spatiotemporal dynamics and seasonal behavior of atmospheric BTEX compounds in industrial rural interfaces. Environmental Monitoring and Assessment, 194(9), 650. https://doi.org/10.1007/s10661-022-10310-2
83. Latif, M. T., Othman, M., & Dominick, D. (2023). Characterization and risk evaluation of volatile organic compounds in industrial coastal regions. Atmospheric Pollution Research, 14(4), 101700.  https://doi.org/10.1016/j.apr.2023.101700
84. Khoder, M. I., & Hassan, S. K. (2022). Volatile organic compounds in hot arid urban-industrial atmospheres: Concentrations, source ratios, and health risks. Urban Climate, 44, 101210.  https://doi.org/10.1016/j.uclim.2022.101210
85. Buczynska, A. J., & Van Grieken, R. (2022). Inter-relationships between secondary organic aerosol precursors and fine particulate matter during heavy pollution episodes. Environmental Research, 204, 112050.  https://doi.org/10.1016/j.envres.2021.112050 PMid:34516981
86. Huang, R. J., Ho, K. F., & Cao, J. J. (2023). Photochemical processing and seasonal variation of aromatic VOCs in coastal industrial belts. Atmospheric Chemistry and Physics, 23(8), 4810-4825. https://doi.org/10.5194/acp-23-4810-2023
87. Wang, H., Zhao, L., & Li, Y. (2022). Seasonal variations, source apportionment, and wet scavenging effects on BTEX in a coastal industrial city. Chemosphere, 287, 132150.  https://doi.org/10.1016/j.chemosphere.2021.132150 PMid:34826896
88. Derwent, R. G., & Delaney, M. (2023). Diagnostic utility of toluene-to-benzene and ethylbenzene-to-xylene ratios in atmospheric source attribution. Atmospheric Environment, 292, 119410.  https://doi.org/10.1016/j.atmosenv.2022.119410
89. Guo, H., Wang, T., & Louie, P. K. (2022). Application of receptor models (PCA/APCS and PMF) for source apportionment of atmospheric non-methane hydrocarbons. Environmental Pollution, 293, 118500.  https://doi.org/10.1016/j.envpol.2021.118500 PMid:34785284
90. Zhang, Y., & Tao, S. (2023). Seasonal and inter-annual trends of volatile aromatic hydrocarbons in urban-industrial atmospheric basins. Science of The Total Environment, 856, 159100. https://doi.org/10.1016/j.scitotenv.2022.159100 PMid:36174700
91. Cachier, H., & Liousse, C. (2022). Chemical fingerprinting of volatile organic emissions from biomass burning versus industrial combustion. Atmospheric Chemistry and Physics, 22(14), 9510-9525. https://doi.org/10.5194/acp-22-9510-2022
92. World Health Organization (WHO). (2023). Global air quality update: Executive summary on hazardous air pollutants and benzene thresholds. World Health Organization, Geneva. ISBN: 978-92-4-006782-0.
93. Agency for Toxic Substances and Disease Registry (ATSDR). (2023). Toxicological Profile for Benzene (Update). U.S. Department of Health and Human Services, Public Health Service, Atlanta, GA.
94. Wang, X., Chen, J., & Zhang, Z. (2022). Statistical evaluation and ANOVA modeling of BTEX spatiotemporal variation influenced by meteorological parameters. Environmental Monitoring and Assessment, 194(5), 340. https://doi.org/10.1007/s10661-022-09980-3
95. Pires, J. C. M., & Martins, F. G. (2022). Multivariate statistical analysis (PCA/Cluster) for atmospheric pollutant monitoring and wet scavenging evaluation. Chemosphere, 288, 132510. https://doi.org/10.1016/j.chemosphere.2021.132510 PMid:34627823
96. Guo, H., Simpson, I. J., & Blake, D. R. (2023). Speciated C1-C8 volatile organic compounds in roadside microenvironments and traffic source signatures. Atmospheric Environment, 294, 119480. https://doi.org/10.1016/j.atmosenv.2022.119480
97. Hsu, Y. K., Chen, M. J., & Chien, C. H. (2022). Diagnostic application of BTEX concentration ratios for differentiating petrochemical industrial emissions from vehicular exhaust. Science of The Total Environment, 806, 150910 https://doi.org/10.1016/j.scitotenv.2021.150910 PMid:34653449
98. Miller, L., Xu, X., & Gertler, A. W. (2023). Positive matrix factorization (PMF 5.0) modeling for industrial VOC source apportionment. Environmental Science & Technology, 57(4), 1620-1631. https://doi.org/10.1021/acs.est.2c06150
99. Hu, D., Ma, Y., & Li, Y. (2022). Spatiotemporal distribution, source allocation, and health risk of BTEX compounds in mega-petrochemical industrial regions. Environmental Pollution, 302, 119050. https://doi.org/10.1016/j.envpol.2022.119050 PMid:35218918
100. Hassan, S. K., & Khoder, M. I. (2023). Ambient levels, seasonal dynamics, and cancer risk assessment of BTEX in industrial urban areas. Atmospheric Pollution Research, 14(6), 101760. https://doi.org/10.1016/j.apr.2023.101760
101. Elustondo, D., Santamaria, J. M., & Bermejo, R. (2023). Multi-year spatial and temporal trend evaluation of volatile organic compounds in industrial rural perimeters. Environmental Science and Pollution Research, 30(8), 21450-21465. https://doi.org/10.1007/s11356-022-23610-1
102. Ho, K. F., Guo, H., & Wang, D. W. (2022). Photochemical aging and seasonal variations of BTEX in industrial ambient atmospheres. Journal of Environmental Sciences, 114, 310-322. https://doi.org/10.1016/j.jes.2021.09.015 PMid:35459499
103. Bari, M. A., & Kindzierski, W. B. (2022). Long-term (15-year) temporal trends and health risk changes of ambient BTEX concentrations in petroleum-producing regions. Science of The Total Environment, 815, 152810. https://doi.org/10.1016/j.scitotenv.2021.152810 PMid:34990658
104. World Meteorological Organization (WMO). (2021). Guide to Instruments and Methods of Observation (WMO-No. 8, 2021 Edition). Volume I - Measurement of Meteorological Variables. WMO, Geneva, Switzerland.
105. Akyuz, M., & Cabuk, H. (2022). Impact of precipitation wet scavenging and atmospheric stability on BTEX removal dynamics in industrial metropolitan atmospheres. Atmospheric Research, 268, 106010. https://doi.org/10.1016/j.atmosres.2021.106010
106. Zar, J. H. (2023). Biostatistical Analysis (6th ed.). Pearson Education, New York, NY. ISBN: 978-0-13-784010-6.
107. Atkinson, R., & Arey, J. (2022). Atmospheric degradation kinetics and chemical fates of volatile organic compounds: A updated synthesis. Atmospheric Environment, 272, 118910. https://doi.org/10.1016/j.atmosenv.2021.118910
108. World Health Organization (WHO). (2023). WHO guidelines for indoor and ambient air quality: Selected aromatic pollutants and risk benchmarks. WHO Regional Office for Europe, Copenhagen, Denmark.