Characterization of polychlorinated biphenyls in surface sediments of the North End Lake, Port Elizabeth, South Africa

Abstract

The distribution and concentrations of 6 indicator polychlorinated biphenyl (PCB) congeners, nos. 28, 52, 101, 138, 153 and 180, were determined in surface  sediments from the North End Lake in Port Elizabeth, South Africa. Forty-two  surficial sediment samples were collected from different locations covering the  region that receives the majority of the industrial waste, urban effluents and runoff  and thus expected to be contaminated with different degrees of contamination. The analysis was achieved by gas chromatography-mass spectrometry (GC/MS) using  the internal standard method. The total PCB concentrations in the samples ranged from 1.60 to 3.06 ng·g^-1 dry weight (dw). The concentrations of congener profiles showed significant differences. Generally, the highest PCB concentrations were  associated with high organic matter contents and small grain size. The highly  chlorinated PCBs dominated with regards to the levels in sediments. PCB 138 was the major contributor to the total PCBs and was detected at 100% of sites. This study provided a snapshot of the PCB contamination status in the North End Lake  sediments, and allowed for a comparison between the investigated system and other systems worldwide.

Keywords: PCBs, sediments, organic matter, particle size, North End Lake