Forensic Analysis and Source Partitioning of Aliphatic Hydrocarbon Contaminants in Surface Sediments from the Niger Delta, Nigeria

Abstract

Forensic analyses and source partitioning modeling were used in characterizing aliphatic hydrocarbon contaminant compositions in surface sediments from coastal areas of the Niger Delta region of Nigeria. The Total Organic carbon (TOC) contents for the sediments ranged from 0.44 to 4.26% (mean 2.36 ± 1.03). The concentrations of total aliphatic hydrocarbon in the entire study area ranged from 1.65 to 61.34mg/kg dry weight, with overall average of 21.52 ± 22.00. The mean concentrations of aliphatic hydrocarbon (C16 – C31) for the sediments in the upper, middle and lower zones of the study area were in the ranges of 0.04 – 5.44mg/kg, 0.04 – 4.91mg/kg and 0.11 - 10.31mg/kg, respectively. CPI values in the broad range of 0.31 -13.32 for the entire stations is indicative of mixed hydrocarbon inputs. A predominance of odd/even carbon n-alkanes and UCM with different shapes and ranges were observed and suggest inputs from multiple sources. Source partitioning modeling using Factor analyses reduced the data set into three principal components (PCs) confirming inputs from biogenic, anthropogenic and microbial/bacterial sources.