Simultaneous Determination of Polycyclic Aromatic Hydrocarbons and Anthraquinone in Yerba Mate by Modified MSPD Method and GC-MS

Yerba mate (Ilex paraguariensis) is widely consumed in South America and is valued for its bioactive compounds, such as polyphenols and methylxanthines. However, during traditional processing, mainly in the fire-based scorch and drying steps, polycyclic aromatic hydrocarbons (PAHs) and anthraquinone (AQ), substances with carcinogenic potential, may be formed. This study aimed to develop and validate an analytical method based on the balls-in-tube matrix solid-phase dispersion technique (BiT-MSPD) and analysis by gas chromatography with mass spectrometry (GC-MS) for the simultaneous determination of 16 priority PAHs and AQ in yerba mate. Parameters such as sorbent type, solvent, sample-to-sorbent ratio, and extraction time were optimized. The method showed good linearity (r2 > 0.99), detection limits between 1.8 and 3.6 µg·kg−1, recoveries ranging from 70 to 120%, and acceptable precision (RSD ≤ 20%). The method was applied to 31 yerba mate samples, including 20 commercial samples and 11 collected at different stages of processing. Most commercial samples showed detectable levels of PAHs, with some exceeding the limits established by the European Union. AQ was detected in 40% of the samples, with some values above the permitted limit of 20 µg·kg−1. The results confirm that scorch (sapeco) and drying contribute to contaminant formation, highlighting the need to modernize industrial processing practices. The proposed method proved to be effective, rapid, and sustainable, representing a promising tool for the quality control and food safety monitoring of yerba mate.