Polycyclic Aromatic Hydrocarbons Contamination and Quality of Locally Produced Crude Palm Oil in South-South Zone, Nigeria

Background: Oil palm, Elaeis guineensis Jacq is a perennial crop mainly cultivated for its vegetable oil. The fatty acid composition of crude palm oil (CPO) is mostly composed of palmitic, stearic oleic, and linoleic acids.

Objectives: This study evaluated the quality of locally produced CPO from six states of South-South zone, Nigeria.

Methods: The parameters of CPOs were characterized by specific gravity (SG), acid value (AV), percentage of free fatty acid (%FFA), and saponification value (SV) and peroxide value (PV). Polycyclic aromatic hydrocarbons (PAHs) in CPO were quantified using standard procedures, the related risk due to daily consumption of 25 g was characterized by lifetime cancer risk (LCR) and margin of exposure (MOE).

Results: The study observed that the mean values of the parameters were 0.931 SG; 5.01 mgKOH g-1 AV; 2.28% FFA; 177.27 mgKOH g-1 SV and 29.65 meqO2 kg-1 PV. Apart from %FFA, the others did not meet the requirements recommended by the Codex Alimentarius Commission of the joint WHO/FAO. Diagnostic ratios of PAHs suggested a mixture of petrogenic and pyrogenic origins. The MOEs showed low health concern while 16PAH-LCR values which ranged from 2.48E-04 - 4.48E-04 were unacceptable. The screening value 0.003 was significantly (p> 0.05) lower than the computed total BaP equivalent (BaPeq) values indicating potential human health concerns. It is recommended that CPO processing and storage methods should be properly monitored to prevent quality reduction and contamination, which might have adverse effect on consumers.