A comparative Study on Bioaccumulation of BTEX and Oxidative Stress Biomarker Response in Parasitised and Non -Parasitised Parachanna obscura (GUNTHER, 1861) from Lekki Lagoon, Lagos, Nigeria

Document Type : Original Article


1 Department of Zoology, University of Lagos, Akoka, Lagos State, Nigeria

2 Department of Biological Sciences, Yaba College of Technology, Lagos.

3 Department of Biological Sciences, Crawford University, Igbesa, Ogun, Nigeria

4 Department of Biological Sciences, Covenant University, Ota, Ogun State, Nigeria


Background: The study was aimed at investigating the bioaccumulation of BTEX in Parachanna obscura, its enteric parasite, Procammalanus sp < /em>, water and sediment collected from Lekki lagoon in Lagos, Nigeria. Parasite intensity, antioxidant enzymes, and lipid peroxidation activities were also investigated in the fish.  Ninety-two (92) samples of P. obscura were investigated for BTEX and parasitic infection for a duration of six months. Physicochemical parameters were measured in-situ using a handheld multiparameter probe (Horiba Water Checker Model U50). BTEX was analyzed using Agilent 7890B gas chromatography system with FID and 7683 series injectors. Histopathological analysis of the fish intestine was conducted following standard histopathological measures.
Results:  BTEX was not detected in the sediment but m+p- Xylene and O- Xylene 6.938 µg/g and 5.854 µg/g were detected in the water respectively. P. obscura showed high accumulation of total BTEX in the intestine than in the liver especially Benzene even though benzene was not detected in the water.  The concentration of BTEX was similar in ranges for the parasitized and unparasitized tissues. The parasite recovered from the fish was Procamallanus spp < /em>. The parasite showed little or no depurative capacities for BTEX. The decrease in superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) in conjunction with an increase in Malondialdehyde (MDA) characterized relatively higher susceptibility in the fish. Lipid peroxidation damage is one of the foremost damages to cell components that could be inflicted by BTEX.
Conclusions: It is therefore pertinent that regular monitoring of BTEX in the water body as well as in the biota should be undertaken and regulatory agencies need to ensure that all the oil depots and tank farms situated along the Lagos lagoon treat all their storm waters and effluents in order to reduce its hydrocarbon level before discharge into the lagoon to safeguard human health and integrity of the aquatic habitat.