Abstract

The concentrations of Cr, Cu, Fe, Mn, Pb, Ni, V and Zn in sediment, surface and groundwater were determined in a total of 180 samples acquired bi-monthly for one year to evaluate the impact of bitumen spills. Principal component analysis (PCA) and cluster analysis (CA) were also used to identify the possible sources of contamination. The concentrations of heavy metals in groundwater, surface water and sediment as follows: Fe > Mn > Zn > Cu > Pb > Ni > V > Cr, Mn > Fe > Zn > Cu > Pb > Ni > V > Cr and Mn > Fe > Zn > Pb > Ni > V > Cu > Cr respectively. The average concentrations of Fe, Pb and Mn in groundwater were found to be above the World Health Organization (WHO) drinking-water quality standard of 0.1, 0.003 and 0.4 mg L⁻¹ respectively. Multivariate analysis suggests significant intrusions of two diagnostic heavy metals (Ni and V) into groundwater samples indicating the migration of these trace metals from bitumen into the water sources. Data from this study showed that the child hazard quotient (HQ) for Pb and Mn were all ≥1, contributing up to 55.5% towards the Hazard Index (HI). Furthermore, Cr, Pb and Ni in groundwater were the predominant contributors towards carcinogenic risks with Ni contributing an average of 81.7% towards the aggregate cancer risk. These results showed significant petroleum contamination that could lead to heavy metal bioaccumulation in residents with a potential threat to public health. Conclusively, these results provide a useful reference for water system management of metals in Agbabu environment.

摘要

在一年两次的双月采样中，测定沉积物，地表和地下水中Cr，Cu，Fe，Mn，Pb，Ni，V和Zn的浓度，以评估沥青泄漏的影响。还使用主成分分析（PCA）和聚类分析（CA）来确定可能的污染源。地下水，地表水和沉积物中的重金属浓度如下：Fe> Mn> Zn> Cu> Pb> Ni> V> Cr，Mn> Fe> Zn> Cu> Pb> Ni> V> Cr和Mn> Fe > Zn> Pb> Ni> V> Cu> Cr 发现地下水中Fe，Pb和Mn的平均浓度高于世界卫生组织（WHO）饮用水水质标准0.1、0.003和0.4 mg L ^-1分别。多变量分析表明，两种诊断重金属（Ni和V）大量侵入地下水样品，表明这些痕量金属从沥青迁移到水源中。这项研究的数据表明，铅和锰的儿童危害商（HQ）均≥1，对危害指数（HI）的贡献高达55.5％。此外，地下水中的Cr，Pb和Ni是致癌风险的主要贡献者，Ni对总癌症风险的平均贡献率为81.7％。这些结果表明，石油污染严重，可能导致居民体内重金属的生物蓄积，对公共健康构成潜在威胁。结论是，这些结果为Agbabu环境中金属的水系统管理提供了有用的参考。