Gas chromatography-mass spectrometry determination of polycyclic aromatic hydrocarbons in baby food using QuEChERS combined with low-density solvent dispersive liquid-liquid microextraction

A sensitive GC-MS method is reported for the determination of twelve polycyclic aromatic hydrocarbons (PAHs) in baby food. The sample preparation involves QuEChERS extraction combined with low-density solvent dispersive liquid-liquid microextraction (LDS-DLLME) and ultra-low temperature (-80 degrees C). Plackett-Burman screening design was employed to identify the main sample preparation variables that affect the extraction efficiency, such as the volume of toluene used in LDS-DLLME. The suitability of proposed method was verified by analytical selectivity, linearity in solvent and matrix-matched calibration curves and adequate recoveries (72-112%) and precision (RSD values <= 11%), under repeatability and within-laboratory reproducibility conditions. High analytical sensitivity was achieved for the monitoring of PAHs at the strict limit of 1 mu g kg(-1) fixed by the European Commission for baby foods. The validated method was applied to thirty-two commercial baby food samples, and the investigated PAHs were not detected in any sample.