Scientific African (Jul 2022)
Soil adsorption coefficient and bioaccumulation of PBDEs in the liver, intestine and parasites of Heterotis niloticus of Lekki Lagoon, Lagos State, Nigeria
Abstract
ABSTRACT: The study aimed at investigating the adsorption capacities of polychlorinated diphenyl ethers (PBDEs) on bottom sediment of Lekki lagoon and the subsequent uptake of the chemical from the soil into the tissues of H. niloticus in the lagoon. The study further aimed at investigating the comparative or synergistic roles of two endoparasites of host Heterotis niloticus, namely Tenuisentis niloticus and Sandonella sandoni in modulating the accumulated PBDEs in Lekki lagoon, Lagos State, Nigeria. The concentrations of PBDE congeners were tested in the water, soil, and the liver, intestine and enteric parasites of H. niloticus using gas chromatography mass spectrometer (GC-MS). Most importantly, the two PBDE congeners of greatest biota-sediment accumulation concerns were BDE-47 and BDE-99. Unfortunately, both parasites showed poor bioaccumulation potentials for BDE-47 which had great adsorption coefficient. This indicates that the aquatic habitat requires stringent monitoring of this congener in order to forestall the prognostic health and environmental hazards this cause. This study however demonstrated that T. niloticus exhibited better sequestration potentials for BDE-183, BDE-99 and BDE-100 than S. sandoni. Although the latter also showed appreciable sequestration potential for BDE-183. Of the two PBDE congeners that exhibited the greatest threats T. niloticus showed promising potentials to bioaccumulate one. The study showed that the synergy of both parasites may depurate some of the toxicant burdens in the host fish H. niloticus. We recommend further study into the possibilities of harnessing the synergy of other harmless bioremediation techniques in order to combat the prognosis of health and environmental hazards BDE-47 may pose. We hereby recommend T. niloticus as a better bioaccumulator and bioindicator of selected PBDEs in the lagoon than S. sandoni.
