Enhanced Detection of Benzo[a]pyrene in Olive Oil through Low Temperature Liquid-Liquid Extraction Coupled with Constant Energy Synchronous Fluorescence Spectroscopy

Refined processed olive oil can indeed become significantly contaminated with polycyclic aromatic hydrocarbons (PAHs). To assess exposure to these contaminants, benzo[a]pyrene (B[a]P) is utilized as a marker due to its known carcinogenicity in humans. The European Commission has established a maximum limit of 2 μg kg^-1 for B[a]P in edible oils. However, the analysis of trace amounts of B[a]P in a complex matrix like olive oil poses a persistent challenge. In this study, we have developed a low-temperature liquid-liquid extraction method in combination with constant energy synchronous fluorescence analysis for the determination of B[a]P in olive oil samples. The analyte was extracted from the olive oil using a mixture of acetonitrile and acetone. The performance of fluorescence measurements was evaluated by carefully considering the effects of solvent, temperature, acetone quenching, and slit width for monochromators. The proposed method demonstrates a linear range from 0.8 to 3.2 μg kg^-1, with limits of detection and quantification of 0.04 and 0.80 μg kg^-1, respectively. Precision and trueness assessments revealed relative standard deviations of less than 10% and recovery rates ranging from 103 to 112%. This method presents an efficient and rapid alternative to sample preparation procedure that minimizes organic solvent consumption.

Keywords:
benzo[a]pyrene; olive oil; fluorescence spectroscopy