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.

Occurrence of a Polychlorinated Biphenyl (PCB) Congener in Surface Water, Sediments and Blackchin Tilapia (<i>Sarotherodon melanotheron</i>) from Ologe Lagoon, Nigeria

“…In other parts of Nigeria, PCBs levels in sediments from Choba River (0.1701 µgg -1 ) (Archibong et al, 2017), Ona River (589 -1353.6 µg/kg) and Ogun River (322.9-2002.6 µg/kg) (Adeogun et al, 2016) were much higher than those in the present study. In comparison to studies conducted in other African countries and countries outside Africa, levels of the PCB compound in sediments in the present study were lower than most of the levels reported by Kampire et al, (2017) Although the concentrations in sediments in the present study were relatively low, Obanya et al, (2018) asserted that chronic exposure to low concentrations of toxicants plays a greater role in toxicology than acute exposure. Surface Water: The results obtained from the lagoon surface water analysis indicated that 0.00133± 0.000667mg/L of 2,4,4'-TCB was detected in surface water from Zone 3 during the rainy season (Figure 3).…”

Unexpected bias of freeze-drying on the performance assessment of chemical oxidation of soils contaminated by polychlorinated biphenyls

“…In this confined zone, the finer particles containing probably the PCBs (Perad 1996; Rybnikova 2016) react with the freeze-concentrated oxidant. Indeed, PCBs, that are hydrophobic compounds, are usually located on soil organic matter or silts and clays containing high extent of organic carbon, which account to the finest fraction of soil (Kampire 2017;Wilcke 1998). A second possibility is that upon freezing, pre-melted films are formed between the surfaces of soil grains and ice lens (Ji 2018;Peppin 2013;Xu 2018).…”

Determination of Occurrences, Distribution, Health Impacts of Organochlorine Pesticides in Soils of Central China

“…One gram of soil sample was thoroughly blended and homogenized with three grams of C18 using a glass mortar and pestle for 5 min [29]. One gram of anhydrous sodium sulfate (Na 2 SO 4 ), 1 g of Florisil, and 1 g of neutral silica gel were added to remove any trace of water and form a free-flowing powder [31] and then 1 g of activated copper powder was added to remove elemental sulfur [24,31]. The activated Na 2 SO 4 , Florisil, neutral silica gel, and copper powder were packed into a 10 mL syringe barrel column with 0.22 μm membrane filter from bottom to top.…”