Analysis of Polycyclic Aromatic Hydrocarbons in Smoked Fish Consumed in Calabar Markets, Cross River State

Smoked fish is a widely consumed, affordable protein source across Nigerian communities, yet the smoking process can generate polycyclic aromatic hydrocarbons, which are known carcinogens that accumulate in food matrices. This study determines the concentrations of selected polycyclic aromatic hydrocarbons in smoked fish species commonly sold in Calabar markets, Cross River State, South South Nigeria. Four fish species, Clarias gariepinus, Scomber scombrus, Synodontis clarias, and Ethmalosa fimbriata, were purchased from three major markets and subjected to saponification and liquid-liquid extraction followed by analysis by high-performance liquid chromatography with fluorescence detection. Results show that benzo(a)pyrene was detected in all samples, with concentrations ranging from 0.4 to 8.7 micrograms per kilogram. Three samples exceeded the European Union regulatory limit of 2 micrograms per kilogram for benzo(a)pyrene in smoked fish. Total PAH4 concentrations, the sum of benzo(a)pyrene, chrysene, benzo(b)fluoranthene, and benzo(a)anthracene, were also computed. Fish smoked over direct charcoal fire showed considerably higher PAH concentrations than those smoked using clay kilns with indirect heat exposure. Cancer risk assessment suggests that regular consumption of directly smoked fish at detected PAH levels poses a low to moderate incremental lifetime cancer risk. The study recommends promotion of improved fish smoking kilns and regulatory testing of smoked fish at point of sale. Keywords: polycyclic aromatic hydrocarbons, smoked fish, Calabar, HPLC, food safety