Biomonitoring of Heavy Metals Pollution in the University of Lagos, Akoka Campus Environment using the Moss Mnium Hornum Hedw

Abstract

Abstract This study investigated the deposition of heavy metals pollution in the University of Lagos, Akoka campus using the moss (Mnium hornum Hedw.) as a bioindicator. Samples of M. hornum. were collected in 2019 from four different locations within the University of Lagos campus: Faculty of Engineering (FE), Lagoon Front (LF), Main Library (ML) and Akintunde Ojo Library (AKT). A control sampling was done at First Estate, Amuwo-Odofin LGA (CL). The concentrations of Cadmium (Cd), Cobalt (Co), Chromium (Cr), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni), Lead (Pb), and Zinc (Zn) were determined using the Atomic Absorption Spectrometer. Results confirmed the presence of heavy metals in this order Fe>Zn>Mn>Cu>Pb>Ni>Co>Cr>Cd. The concentrations of the examined heavy metals across the locations were lowest in CL except Ni which was lowest in FE and LF (0.03mg/kg). While there was no significant difference in the concentrations of Cd, Co, Cr, Cu, Mn, Ni, and Pb among locations, both Fe (66.00mg/kg) and Zn (64.33mg/kg) were significantly higher in ATK than in the other locations. The contamination factor suggests that ML (C2), FE (C3) and LF (C3) were moderately contaminated while AKT (C5) was seriously contaminated. The index of geo-accumulation revealed that FE (Igeo4) and ML (Igeo4) are moderate to severely polluted, LF (Igeo5) was severely polluted and AKT (Igeo7) was extremely polluted with the assayed metals. The difference in the occurrence of anthropogenic activities was seen to be the major factor responsible for the variations in the concentration of heavy metals accumulated by the mosses.