Trace amount determination of monocyclic and polycyclic aromatic hydrocarbons in fruits: Extraction and analytical approaches

Two reliable and complementary approaches have been established for the determination of volatile and semi-volatile aromatic hydrocarbons at μg/kg level in fruits. Headspace solid-phase microextraction was used for extraction of monocyclic and light polycyclic aromatic hydrocarbons (MW ≤ 178 g/mol). Method based on ultrasound-assisted extraction followed by solid-phase extraction allowed extraction of heavy polycyclic aromatic hydrocarbons (MW ≥ 202 g/mol). Extraction techniques coupled with analysis by gas chromatography-mass spectrometry were successfully applied to 18 aromatic compounds in different fruit matrices (apple, pear, plum, and grape). Applicability of methods to these several fruits had been statistically verified through ANOVA test, by comparison of linear regression responses (slopes) of calibrations curves. Developed methods showed good linearity (r2 = 0.919-0.999) within a range of concentrations from 0 to 10 μg/kg wet weight and acceptable values were obtained for repeatability (RSD = 1-22%) and intermediate precision (RSD 3-30%). Limits of detection and quantification did not exceed 0.2 and 0.6 μg/kg, respectively, except for fluorene in grape (0.5 and 1.8 μg/kg, respectively). Extraction and analytical methodologies implemented in the present study allow sensitive determination of trace levels of monocyclic and polycyclic aromatic hydrocarbons in fruit.