Distribution and Carcinogenicity of PCBs in Soil Contaminated with Transformer Oil in Selected Locations in Jos, Plateau State Nigeria

Abstract

Soil from the vicinity of transformers installation in different locations in Jos, Plateau State was investigated for Polychlorinated Biphenyls (PCBs). The assessment was carried out for both total PCBs and congeners using Agilent 6975 GC-MS in ten different locations. The soil samples were extracted with 1:1 hexane- acetone in an ultrasonic bath, concentrated and cleaned with column chromatography using silica gel and hexane as eluting solvent. The result shows five locations were polluted with PCBs that exceed the maximum limit of 2.0mg/kg as permitted by the United States Toxic Substance Control Act (TSCA) with the following values NGS 1 (14.25), NGS 3 (4.47), NGS 6 (9.48), NGS 9 (8.21) and NGS 10 (5.05) while the others have NGS 2 (0.64), NGS 4 (1.85), NGS 5 (0.83), NGS 7 (0.95) in mg/kg respectively, NGS 8 value was below the instrument detection limit (0.0012mg/kg). The order for the total PCBs concentration in these selected locations are NGS 1 > NGS 6 > NGS 9 > NGS 10 > NGS 3 > NGS 4 > NGS 7 > NGS 5 > NGS 2. The carcinogenicity of the dioxin-like PCBs calculated as total toxicity equivalence concentration (TTEC) in these selected locations corresponds to NGS 1 (0.00001), NGS 2 (0.0000051), NGS 3 (0.0000054), NGS 4 (0.0000051), NGS 6 (0.0000063), NGS 7 (0.0000078), NGS 9 (0.0000051) and NGS 10 (0.0000051) respectively. The total cancer risk computed by addition of cancer risk due to ingestion, inhalation and dermal contact revealed that all the locations have very low to low cancer risk compared with the value recommended by the United State.

Progress on Drinking Water Quality Monitoring in the Northern Part of Nigeria: A Catalyst to Achieving Sustainable Development Goals

“…This was attributed to the high level of contamination from different sources, as proved by the most deviated biological and radiological parameters against standards set by recognized local and international organizations. The concentration of heavy metals and microbiological loads in the water was significantly high and is a major roadblock to portable water for northerners (Ibrahim et al, 2020;Musa et al, 2020;Aliyu et al, 2020;Ogbozige et al, 2017;Haruna et al, 2016;Allamin et al, 2015;Ojo et al, 2014). Chemical and microbial contamination of the water was attributed to the high rate of population growth and several anthropogenic activities, as well as lack of access to enough water for sanitation and hygiene (Odey et al, 2022;Raji et al, 2020;Emurotu and Habib, 2019;Fardami et al, 2019;Sunday et al 2019;Omotayo et al, 2017;Zubairu et al, 2016).…”

Concentrations and risks of PCBs in soil contaminated with transformer oil in selected locations in Warri South Local Government Area, Delta State, Nigeria

“…Even though PCBs are known to bioaccumulate, this problem needs to be resolved. [36,37] found that the overall PCBs content in soil from transformer installation sites in University of Port Harcourt and Jos metropolis was greater than 2.00 mg/kg. These statistics (Table 6) demonstrate that we are far less polluted than more developed countries like China and the US [38,39] when compared to other studies from around the world.…”