Magdalena Surma

Comparison of different modifications on QuEChERS sample preparation method for PAHs determination in black, green, red and white tea

The aim of this work was the evaluation of QuEChERS extraction method for polycyclic aromatic hydrocarbon (PAH) determination in various types of tea. In the experiment, different kinds of extraction solvents, sorbents and a final method of sample preparation were compared. The final extracts were analysed by gas chromatography-selected ion monitoring-mass spectrometry. The results suggest that acetonitrile extraction, clean up with SAX and final liquid–liquid extraction was the best combination giving the most purified extracts and acceptable compound recoveries for different types of teas. In the study of real samples, compounds belonging to light PAHs were mostly detected, and heavy polycyclic aromatic hydrocarbons, including benzo[a]pyrene, were not identified in any of samples.

Determination of perfluorinated sulfonate and perfluorinated acids in tissues of free-living European beaver (castor fiber L.) by d-SPE/ micro-UHPLC-MS/MS

Perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) are the main representatives of an rising class of persistent organic pollutants (POPs), perfluorochemicals (PFCs). In this study, determination of selected PFCs concentration in liver, brain, tail, adipose and peritoneum tissues of free-living European beaver (Castor fiber L.) was addressed. Tissue samples, collected from beavers living in Masurian Lakeland (NE Poland), were analyzed by dispersive Solid Phase Extraction (d-SPE) with micro-UHPLC-MS/MS system. In a group of ten selected pefrluorinated compounds only two perfluorinated acids (PFOA and PFNA) and one perfluorinated sulfonate (PFOS) were quantified. PFOA was detected in all analysed tissue samples in both female and male beavers in a range from 0.55 to 0.98ngg(-1) ww whereas PFOS was identified in all analyzed female beaver tissues and only in liver, subcutaneous adipose and peritoneum tissues of male beavers at the concentration level from 0.86 to 5.08ngg(-1) ww. PFNA was only identified in female beaver tissues (liver, subcutaneous adipose and peritoneum) in a range from 1.50 to 6.61ngg(-1) ww. This study demonstrated the bioaccumulation of PFCs in tissue samples collected from beavers living in area known as green lungs of Poland. The results provided in this study indicate for the increasing risk of PFCs occurrence in the environment and the level of PFCs in tissue of free-living European beavers may serve as bioindicator of environmental pollution by these compounds.

In vitro evaluation of the cytotoxicity and modulation of mechanisms associated with inflammation induced by perfluorooctanesulfonate and perfluorooctanoic acid in human colon myofibroblasts CCD-18Co.

Perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) are the most notable members of an emerging class of persistent organic pollutants (POPs), poly- and perfluoroalkyl acids (PFASs). In this study, the CCD-18Co myofibroblasts were selected as a cell model to investigate the cytotoxic effects of PFOS and PFOA. The aim was to perform an in vitro evaluation of the ability of these compounds to induce cytotoxicity and modulate mechanisms associated with inflammation as measured by (i) colon fibroblasts viability, (ii) colon fibroblasts proliferation, and (iii) IL-6 production. The data provided in this study suggest that PFOS and PFOA can have cytotoxic potential and modulate processes associated with intestinal inflammation such as myofibroblasts proliferation and IL-6 production at concentrations similar to those detected in vivo. Our results also highlight the influence of culture serum concentration in cytotoxic in vitro studies, which should be considered in future toxicity studies involving PFOS and PFOA. The results contribute to a better knowledge of the effects of PFOS and PFOA in human cells, a phenomenon still not fully examined.

Development of a new analytical method for the determination of red beetroot betalains using dispersive solid-phase extraction.

The objective of this study was to develop a method for the determination of red beetroot betalains based on the dispersive solid-phase extraction and modified QuEChERS methods followed by micro-high performance liquid chromatography coupled with a mass spectrometer that was equipped with a quadrupole and time-of-flight detector. Currently, new techniques for the extraction of the pigments are necessary and in this study, an extraction of beetroot betalains based on the QuEChERS method was developed for the first time. Twelve variants of the methods with different sorbent combinations were tested. The extraction with 15% methanol and with 0.05% formic acid was performed as a reference method to compare the obtained results. In all of the samples with the addition of sorbents, a lower noise was demonstrated in the obtained results. The betalain concentrations obtained using the tested methods were 0.32-0.54 mg g(-1) , while the value of the reference method was 0.44 mg g(-1) . The method that used the strong ion exchange sorbent (0.44±0.05 mg g(-1) ) was the most adequate in terms of analyzed content, related standard deviation value and interference compared to the reference method. It was concluded that the properly modified QuEChERS method can be successfully applied for the determination of red beetroot betalains.

Development of a sample preparation method for acrylamide determination in cocoa via silylation

This paper reports the development of a rapid and simple sample preparation method for acrylamide (AA) determination in cocoa powder through conversion to N,O-bis(trimethylsilyl)acrylamide. The AA level was quantified in relation to an acrylamide-d3 internal standard using gas chromatography coupled with ion-trap mass spectrometry in the single ion monitoring mode (GC-SIM-MS). The analytical procedure consisted of extraction with an organic solvent (acetonitrile with/without hexane addition), extract purification by dispersive solid-phase extraction (d-SPE) using various sorbents (SAX, C18, ENV, Florisil) apart from the PSA sorbent, followed by derivatisation with N,O-bis (trimethylsilyl) trifluoroacetamide (BSTFA) and finally chromatographic analysis (GC-SIM-MS) using a deuterated internal standard. Nine variants of the method were tested. The usefulness of the method has been verified based on the recovery ratio of acrylamide. The obtained results showed that the best recovery of 98.2% with RSD lower than 10% was obtained using a combination of sorbents PSA and C18 with the addition of hexane in the initial stage of the extraction. The developed method has been successfully applied to the determination of acrylamide in 9 cocoa powder and 30 chocolate (dark, milk and white) samples purchased at a Polish supermarket. The results of AA content ranged from 54.2 to 168.0 μg kg−1 and from 25.5 to 256.1 μg kg−1 in cocoa powder and chocolate, respectively. The obtained results were in good agreement with literature reports.

The perfluoroalkyl substances (PFASs) contamination of fruits and vegetables

ABSTRACT Fruit and vegetables play a major role in human nutrition due to richness of nutrients, dietary fibre, and phytochemicals. As dietary intake is identified as one of the dominant exposure pathways to perfluoroalkyl substances (PFASs), a cross-sectional study involving determination of their levels in food of plant origin has been conducted. Locally-grown and imported fruit and vegetable samples, collected in 2016 were inspected for 10 perfluoroalkyl acids (PFAAs) using QuEChERS as sample pre-treatment procedure followed by micro-HPLC-MS/MS. Three of 10 target analytes, perfluorobutanoic acid (PFBA), perfluorooctanoic acid (PFOA), and perfluorooctane sulfonate (PFOS) were quantitatively determined. The detection frequency for PFASs across the 55 samples analysed was less than 10%. The major contributor of the total PFASs concentration in the investigated group was PFBA for which the concentration, reported only for banana, apple and orange samples, was 50.740 ng g−1 ww. The most often detected compound was PFOA. The origin and growing region are possible factors with the potential to influence PFASs distribution profile and their levels in food.