Bioaccumulated polychlorinated biphenyls (PCBs) levels in three aquatic fauna specimens obtained from a continually perturbed fresh water mangrove swamp location in Southern Nigeria

Abstract

This study evaluated the presence of 15 polychlorinated biphenyls (PCB) congeners in three aquatic faunal organisms; mudskipper (Periopthalmus barbarous), crab (Sesarma alberti) and periwinkle (Tympanotonus fuscatus) obtained from different sampling points in the Falcorp mangrove swamp located in Delta State, Nigeria. Gas chromatography was used in the determination of PCB concentrations in the faunal specimens. The resulting PCB data obtained were analyzed using descriptive and inferential statistical tests. The PCB 2,2',3,3',4,5',6,6'-Octachlorobiphenyl was not detected in any sample while the observed maximal values were: mudskipper - 2,2',3,3',4,4',6-Heptachlorobiphenyl (0.1794mg/kg); crab - 2,3,3',4,4',5',6- Heptachlorobiphenyl and 2,2',3,3',4,4',6 -Heptachlorobiphenyl (0.1107mg/kg); and 4,4'-Dichlorobiphenyl (0.0402mg/kg). The detection of bioaccumulated PCBs in the respective aquatic fauna has raised important inquires pertaining to likely long-term negative effects of PCB contamination on ecosystem health as well as public health safety as these aquatic faunae are commonly consumed among residents living within the vicinity of the swamp. Results of this research has also highlighted an urgent need for continuous environmental monitoring by public and concerned stakeholders as well as an increased stringent regulatory oversight of the release of persistent pollutants such as PCBs into different environmental matrices particularly mangrove wetlands.