Evaluation of Sources of Polycyclic Aromatic Hydrocarbons in Thermally Treated Meat and Fish: A Food Pollutant Study

This study assessed the sources of PAH in cooked meat and fish. Gas Chromatography-Mass Spectrometry (GC-MS) performed the sample analysis. The total PAH concentrations (mg/kg) ranged from 0.911 to 2.763. Levels of low-molecular-weight (LMW) PAHs varied from 0.353 mg/kg to 1.786 mg/kg, while high-molecular-weight (HMW) PAHs ranged from 0.516 to 0.977 mg/kg. The study detected 2 to 6-ring PAHs, the 3-ring PAHs were the most prominent. PAHs diagnostic ratios, their plots and principal component analysis (PCA) were used to assess the origin of PAHs in the samples. Values of diagnostic ratios, such as Phenanthrene/Anthracene (1.84–3.58), Anthracene/(Anthracene + Phenanthrene) (0.21–0.35), Fluoranthene/Pyrene (0.00-1.79), Fluoranthene /(Fluoranthene + Pyrene) (0.00-0.64), Indeno[123-cd-]pyrene/(Indeno[123-cd-]pyrene + Benzo[ghi]perylene) (0.00–43), LMW-PAH/HMW-PAH (0.59–1.83) and Benzo[a]pyrene/(Benzo[a]pyrene + Chrysene) (0.00–0.50) indicated that the PAHs in the samples were from mixed sources, with greater contributions from pyrogenic sources. They show that the barbecued samples were contaminated primarily by pyrogenic PAHs (biomass (wood/charcoal) burning, liquid fuel combustion, or automobile exhaust emissions). The grilled and smoked samples were mostly contaminated from different combustion sources (traffic and non-traffic, biomass burning, automobile exhaust and liquid fuel), with little input from petrogenic sources. The combination plots of the ratios also show that PAH was from mixed sources (petrogenic and pyrogenic), but mostly from a pyrogenic source (wood/charcoal burning, liquid fuel combustion, and automobile exhaust emissions) with minor inputs from petrogenic origin, as shown by the value of LMW-PAH/HMW-PAH ratios > 1 in a few samples. PCA equally showed that four factors accounted for 82.47% of the total variability and separated the PAHs into identifiable source groups, comprising mixed sources, combustion of liquid fossil fuel, automobile/diesel engine exhaust, gasoline and oil combustion and biomass burning. The study showed that contamination from the natural habitats of the animals contributed to the PAHs in them in addition to the cooking process. This therefore underscored the impacts of anthropogenic pyrogenic activities on PAHs formation and levels in meat and fish, hence adequate control/reduction of these activities will promote a healthier and safer food environment for all.