Tongo Isioma, Ezemonye Lawrence, Akpeh Kingsley
Laboratory of Ecotoxicology and Environmental Forensics, Department of Animal and Environmental Biology, Faculty of Life Sciences, University of Benin, Benin, Nigeria.
Environ Monit Assess. 2017 Jun;189(6):247. doi: 10.1007/s10661-017-5931-5. Epub 2017 May 2.
The levels and distribution of polycyclic aromatic hydrocarbons (PAHs) in surface water, sediment, and fish (Clarias gariepinus) samples from Ovia River, Southern Nigeria, were evaluated, to assess the contamination profile, dietary intake, and human health risks associated with exposure. Results showed that naphthalene, acenaphthylene, and fluoranthene were the most dominant contaminant in water, sediment, and fish, respectively, with mean concentrations (μg/L) of 3.08, 45.4, and 90.7. Spatial distribution showed high occurrence of PAHs in Ekenwan, the downstream station, for all the matrices. Source identification using multivariate analysis revealed mixed patterns of pyrogenic and petrogenic origins. Estimated daily intake (EDI) of PAHs through fish consumption ranged from 2.18 × 10 to 5.23 × 10 mg/kg/day; values were however lower than the reference dose (RfD) indicating low risk. Estimated values for hazard quotients (HQs) and hazard index (HI) for both non-carcinogenic and carcinogenic risks were below 1 indicating low risk through dietary and non-dietary exposure to water, sediment, and fish from Ovia River. However, estimated HI values for direct ingestion of sediment were above 1, indicating the possibility of non-carcinogenic health risk from exposure. Carcinogenic risk indices also indicated low risk from fish consumption. In spite of the assessed low risk from exposure, continuous monitoring of PAH levels in this water body is imperative to prevent future human health effects.
对尼日利亚南部奥维亚河地表水、沉积物和鱼类（非洲鲶鱼）样本中的多环芳烃（PAHs）水平及分布进行了评估，以评估污染状况、膳食摄入量以及与暴露相关的人类健康风险。结果表明，萘、苊烯和荧蒽分别是水体、沉积物和鱼类中最主要的污染物，平均浓度（μg/L）分别为3.08、45.4和90.7。空间分布显示，对于所有基质而言，下游站点埃肯万的多环芳烃含量较高。使用多变量分析进行的源识别揭示了热解源和石油源的混合模式。通过食用鱼类摄入多环芳烃的估计每日摄入量（EDI）范围为2.18×10至5.23×10毫克/千克/天；然而，这些值低于参考剂量（RfD），表明风险较低。非致癌和致癌风险的危险商数（HQs）和危险指数（HI）的估计值均低于1，表明通过饮食和非饮食途径接触奥维亚河的水、沉积物和鱼类的风险较低。然而，直接摄入沉积物的估计HI值高于1，表明存在因接触而导致非致癌健康风险的可能性。致癌风险指数也表明食用鱼类的风险较低。尽管评估显示暴露风险较低，但仍必须对该水体中的多环芳烃水平进行持续监测，以防止未来对人类健康产生影响。
