Faboya Oluwabamise L, Sojinu Samuel O, Otugboyega Joseph O
Department of Chemistry, Federal University, Oye-Ekiti, Ekiti State, Nigeria.
Department of Chemistry, College of Physical Sciences, Federal University of Agriculture, Abeokuta, Nigeria.
Heliyon. 2023 Apr 15;9(4):e15508. doi: 10.1016/j.heliyon.2023.e15508. eCollection 2023 Apr.
Crude oil contamination could serve as an important source of polycyclic aromatic hydrocarbons (PAHs) in the environment. Determining the concentration and distribution of PAHs and their ecological risk could provide clues for appropriate remediation. The present study investigated the concentrations, composition pattern, and ecological risk of PAHs in crude oil-contaminated soil collected from the Niger Delta, Nigeria. The concentrations of ΣPAHs and 16 priority US-EPA PAHs (ΣPAHs) in the soil ranged from 24230.68 to 40845.32 ng/g (average: 29953.47 ng/g) and 7361.66-14141.49 ng/g (average: 9819.96 ng/g), respectively. The concentrations of ΣPAHs US-EPA in all the studied locations far exceeded the safety value of 1000 ng/g set by the soil quality guidelines of Switzerland and above which is regarded as being highly contaminated for Agricultural soils of Poland. The percentage composition of 2-, 3-,4-, 5-, and 6-ring in the soils were 33.69%, 56.31%, 9.47%, 0.52%, and 0.02% of the total PAHs, respectively, indicating the predominance of low molecular weight PAHs typical of petrogenic origin. Ecological risk assessment indicated a high risk to the soil biota and ecosystem in the studied soil samples as presented by individual PAH and total PAHs. 2-, 3- and 4-ring PAHs in the soil contributed significantly to the ecological risk burden in the soils. This research work provides useful information on the ecological risk associated with crude oil contamination and consequently would assist the government in formulating precise, targeted, and effective remediation measures for soil contaminated with crude oil.
原油污染可能是环境中多环芳烃（PAHs）的一个重要来源。确定多环芳烃的浓度和分布及其生态风险可为适当的修复提供线索。本研究调查了从尼日利亚尼日尔三角洲采集的原油污染土壤中多环芳烃的浓度、组成模式和生态风险。土壤中总多环芳烃（ΣPAHs）和16种美国环保署优先控制的多环芳烃（ΣPAHs）的浓度分别为24230.68至40845.32 ng/g（平均：29953.47 ng/g）和7361.66 - 14141.49 ng/g（平均：9819.96 ng/g）。所有研究地点的美国环保署总多环芳烃浓度远远超过瑞士土壤质量指南设定的1000 ng/g的安全值，高于该值的土壤被认为对波兰农业土壤具有高度污染。土壤中2环、3环、4环、5环和6环的百分比组成分别占总多环芳烃的33.69%、56.31%、9.47%、0.52%和0.02%，表明主要是典型的石油成因的低分子量多环芳烃。生态风险评估表明，所研究的土壤样品对土壤生物群和生态系统具有高风险，这由单个多环芳烃和总多环芳烃表示。土壤中的2环、3环和4环多环芳烃对土壤中的生态风险负担有显著贡献。这项研究工作提供了与原油污染相关的生态风险的有用信息，因此将有助于政府制定针对原油污染土壤的精确、有针对性和有效的修复措施。
