ABSTRACT
European food legislation defines a set of 16 polycyclic aromatic hydrocarbons (PAHs) as of high concern for human health. The EU set contains structurally very similar PAHs with ring numbers between 4 and 6, and so raises some separation aspects and problems, which were not experienced with traditionally analysed PAHs. Many of the currently applied gas chromatographic mass spectrometric (GC-MS) methods suffer from separation problems, while high performance liquid chromatography with fluorescence detection (HPLC-FLD) is neither capable of detecting the whole set of EU priority PAHs nor does it (compared to GC-MS) allow structural identification. In addition HPLC-FLD shows limitations with difficult matrices due to interferences. The aim of this paper is to fill this gap by describing a liquid chromatographic dopant assisted atmospheric pressure photo ionisation tandem mass spectrometric (LC-DA-APPI-MS/MS) method for the determination of 15+1 EU priority PAHs in edible oil, which complies with the requirements set by European food legislation. Measurements were performed in positive ion mode. Anisole at a flow rate of 30 µl/min was used as dopant. Sample preparation was performed offline by donor-acceptor complex chromatography (DACC). Compared to HPLC-FLD methods the presented method enables the determination of all 15+1 EU priority PAHs at the low µg/kg concentration range including less fluorescence active compounds like benzo[j]fluoranthene and indeno[1,2,3-cd]pyrene. By analysing four reference materials it could be demonstrated that this method provides accurate results and is sufficiently sensitive for food control purposes. Statistically significant differences between the reference values and the measured analyte contents were not found. The method performs well also for very complex samples. Repeatability relative standard deviations (RSDr) of the determination of the target PAHs in olive oil were for most analytes below 5%. The limit of detection (LOD) of the method met the requirement set by EU legislation (0.3 µg/kg).
Subject(s)
Chromatography, Liquid/methods , Food Analysis/methods , Plant Oils/chemistry , Polycyclic Aromatic Hydrocarbons/analysis , Tandem Mass Spectrometry/methods , Anisoles/chemistry , Hot Temperature , Olive Oil , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Intrauterine intestinal volvulus and fetus compressus papyraceus in twins. In a double twin pregnancy revealed on the 16th gestation week by ultrasound examination, a foetus papyraceus was detected on the 20th gestation week in a 29 year old woman. On the 32nd gestational week two monochorionic-diamniotic male stillborn twins were born. One of them (15 cm/35 g) was rudimentary developed and compressed. On examination of the other (39 cm/1485 g) partially macerated foetus, volvulus of small intestine with hemorrhagic necrosis was found at the autopsy. Both of the anomalies are very rare.
