Pollution

Pollution

Separation and Characterization of Polycyclic Aromatic Hydrocarbons (PAHs) from Iraqi Oil Refinery Waste using Gas Chromatography-Mass Spectrometry (GC-MS)

Document Type : Original Research Paper

Authors
Zainab Talib Abd Al-Kadhum 1
Fatma H Abdulla 2
Dhuha T Al-Sultani 3
1 Department of Optometry Techniques, Al-Musaib Technical College, Al-Furat Al-Awsat Technical University, Babylon, Iraq
2 University of Baghdad Al-Jaderyia Campus College of Science-department of biology, Baghdad, Iraq
3 Polymer engineering and Petrochemical Industries Department, University of Babylon, Iraq
10.22059/poll.2026.416175.3373
Abstract
In the paper, polycyclic aromatic hydrocarbons (PAHs) in oil refinery waste produced in Baghdad Province, Iraq were analyzed with the help of gas chromatography-mass spectrometry (GC-MS). Wastewater and sludge samples of various sampling sites were analyzed and found to contain sixteen EPA priority PAHs. Soxhlet extraction method was used to extract the analytes and an Agilent 6890N/5975C GC-MS system equipped with HP-5MS capillary column was used to analyze them. Findings indicated the presence of total PAHs of 567.8 to 3750.7 ng/L in wastewater with high molecular weight PAHs (5-6 rings) taking over the profile (49.41%-81.67% of total PAHs). Phenanthrene, fluoranthene, pyrene and benzo[a]pyrene were the most widespread. Diagnostic ratio analysis and principal component analysis (PCA) revealed that the pyrogenic sources were the main cause of PAHs especially during the combustion of petroleum products and vehicle emissions. The incremental lifetime cancer risk (ILCR) evaluation showed values over 10 -4 which showed a strong carcinogenic risk that must be addressed immediately. The study will yield essential baseline information on monitoring and control of risks on the environments in the oil refining areas of Iraq.
Keywords
Wastewater
Sludge
Carcinogenicity
Source apportionment
Risk assessment
Pyrogenic
Subjects
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Pollution
Volume 12, Issue 3
Summer 2026
Pages 1000-1009