Determination of 4 EU Priority Polycyclic Aromatic Hydrocarbons in Oilseeds by GC-MS/MS Combined with d-SPE QUECHERS Technique

In this study, a method for the simultaneous determination of 4 EU priority polycyclic aromatic hydrocarbons (PAHs): benzo[a]anthracene (BaA), chrysene (ChR), benzo[b]fluoranthene, and benzo[a]pyrene (BaP) from oilseeds by GC-MS/MS was developed and validated. Optimal sample preparation involved the use of modified QuEChERS extraction with hexane, followed by concentration of the extract and collecting it in acetonitrile, and then by two-step purifications, by freezing (-20°C) and by dispersive solid phase extraction (d-SPE QuEChERS). The developed method was validated by evaluating the linearity on solvents (R²=0.9947-0.9987) and sunflower seeds (R²=0.9920-0.9980), matrix effect (≤ ±20%), recovery (81.1-109.8%), precision (RSD=0.4-11.8%) for 3 concentration levels (2, 5 and 7.5 µg/kg), LOD, LOQ, working range, linearity range, and measurement uncertainty. A high analytical sensitivity was obtained for 4 PAHs in oilseeds (LOD=0.05-0.25 µg/kg; LOQ=0.18-0.82 µg/kg), fulfilling the criteria set by the Commission Regulation (EU) No 836/2011. Sunflower seeds (n=27) harvested from different areas of Romania were analysed using the proposed method. The 4 PAHs in the sunflower seeds ranged from not found to detectable and quantifiable concentrations (˃LOQ), with maximum values of 0.56 µg/kg for BaA. BaP, considered a marker for assessing the carcinogenic risk of PAHs in food, it was not quantifiable in any sample but was detected (<LOQ) in about 26% of the analysed oilseeds. The values ​​determined for BaP and the sum of 4 PAHs were below the limits imposed by Commission Regulation (EU) No 835/2011 for oils and fats, of 2 ppb and 10 ppb, respectively.