Evaluation of three extraction methods for the isolation of PAHs from recycled paperboard materials intended for food contact applications

The present work is part of a comprehensive study aiming to identify and quantify an array of harmful contaminants at very low concentrations in recycled paperboard materials intended for food contact applications. In this initial study, three commonly used extraction techniques were optimized and tested for their efficacy and accuracy in isolating 13 polycyclic aromatic hydrocarbons (PAHs) from three commercially available food packaging materials made from recycled paperboard. The techniques were Soxtec extraction (SE), ultrasound-assisted extraction (UAE), and headspace solid-phase microextraction (HS-SPME), followed by gas chromatography-mass spectrometry (GC/MS) analysis. The recoveries of all three methods were rather satisfactory; 10 out of 13 substances were recovered at rates between 70 and 124% using the SE method, 8 out of 13 substances were recovered at rates between 50 and 134% using the UAE method, and finally, 8 out of 13 substances were recovered at rates between 70 and 105% using the HS-SPME method. Regarding accuracy, the HS-SPME method gave the best results at 125 μg kg−1, as 7 out of 13 concentration values were within acceptable limits, while only five and four concentration values were within limits for the UAE and SE methods, respectively. Furthermore, the results of both the calculated RSD and HorRat values indicated that HS-SPME is more accurate for extracting PAHs than the other two methods.