The quantum of polycyclic aromatic hydrocarbon in <em>Pyxicephalus edulis</em> and sediments in Oluwa river, Igbekebo area, Ondo state, Nigeria

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds composed of two or more fused aromatic rings. PAHs can be found in a variety of foods and beverages, including drinking water, vegetables, fruits, cereals, oils, seafood, and meats. The current study investigated the pollution levels of the quantum of polycyclic aromatic hydrocarbon in Pyxicephalus edulis and river sediments. Twenty-five sediment samples and male and female specimens of Pyxicephalus edulis were collected from Oluwa River near Igbekebo, Ondo State Nigeria. The sediment samples were then dried in the open air for three days while the identified frog species were dried separately for 6 hours at 105°C before being powdered. The physicochemical parameters of sediment samples examined using standard physical and chemical analytical techniques and polycyclic aromatic hydrocarbons in frog and sediment samples were examined using gas chromatographyflame ionization analysis (GC-FID). The toxicity equivalent(TEQ) values of PAHs in sediment samples were determined by comparing the findings of this study to the Sediment Quality Guideline (SQG) with effects range from viz., low (ERL), median(ERM) and threshold-effects level (TEL)/probable-effects level (PEL) to assess the toxicity of PAHs to aquatic organisms living in sediments. Male frogs had significantly higher concentrations of Acenaphthylene, Phenanthrene, Anthracene, Pyrene, and total PAHs than females, and lower concentrations of Naphthalene, Acenaphthylene, Fluorene, and Fluoranthene. BaAnt, Benzo(b) fluoranthene, Benzo(k)fluoranthrene, Benzo(a)pyrene, Indeno(1,2,3-cd) pyrene, Dibenz(a,h)anthracene, Benzo(g,h,i)perylene were reported only among males. The cause of this variation is unknown, but it could be due to differences in the genetic make-up of male and female frogs.