Concentration and health risk valuation of polycyclic aromatic hydrocarbons in Tilapia zilli in selected wetlands

Abstract

Globally, food safety is growing, and the residues of PAHs (polycyclic aromatic hydrocarbons) in fish species above the standard threshold could elicit serious public and community health concerns. This study investigated the PAHs contamination concentrations of <i>Tilapia zilli</i> in the wetlands of the Niger Delta. The study was conducted from March to August 2023, and fish samples were collected within these periods from 5 wetlands. The results obtained were as follows: pyrene; 2.46±0.11 µg/kg, chrysene; 2.54±0.12 µg/kg, BaP; 2.52±0.11 µg/kg, BaA; 2.54±0.13 µg/kg and BbF; 2.54±0.13 µg/kg. The mean results of characterising the PAHs in the fish were insignificant at <i>p>0.05</i>. The results of the health risk evaluation showed that Beneze (a) pyrene had the highest value (12.33 µg/kg), followed by Benzo (a) anthracene and Benzo (b) fluoranthene (1.51 and 1.20) of the toxicity equivalent factors. Meanwhile, the sum across the station was significantly higher than the standard limits. The CDI (chronic daily intake) results obtained in this study for each PAH (polycyclic aromatic hydrocarbon) congener were considerably high and fluctuated across the stations. However, the results for the ILCR (incremental life cancer risk) showed that the values were higher (1 × 10⁻²) than the threshold set for this study (1 × 10⁻⁶ to 1 × 10⁻⁴). The fish were thus contaminated above the acceptable limit; therefore, they are not fit for human consumption or for compounding animal feed.