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ObjectivesFew epidemiological studies have studied the effect of 2,3,7,8-tetrachlorodibenzo-p dioxin (TCDD) on blood cytokine levels. In this study we investigated changes in plasma levels of a large panel of cytokines, chemokines and growth factors among workers from a Dutch historical cohort occupationally exposed to chlorophenoxy herbicides and contaminants including TCDD.MethodsEighty-five workers who had been exposed to either high (n=47) or low (n=38) TCDD levels more than 30 years before serum collection were included in the current investigation. Plasma level of 16 cytokines, 10 chemokines and 6 growth factors were measured. Current plasma levels of TCDD (TCDDCurrent) were determined by high resolution gas chromatography/isotope dilution high resolution mass spectrometry. TCDD blood levels at the time of last exposure (TCDDmax) were estimated using a one-compartment first order kinetic model. ResultsBlood levels of most analytes had a negative association with current and estimated past maximum TCDD levels. These decreases reached formal statistical significance for fractalkine, transforming growth factor alpha (TGF-α) and fibroblast growth factor 2 (FGF2) with increasing TCDD levels.ConclusionsOur study showed a general reduction in most analyte levels with the strongest effects for fractalkine, FGF2 and TGF-α. These findings suggest that TCDD exposure could suppress the immune system and that chemokine and growth factor-dependent cellular pathway changes by TCDD may play role in TCDD toxicity and associated health effects.

The plug-and-play hyphenation of UV-laser ablation (LA) and mass spectrometry is presented, using dielectric barrier discharge ionization (DBDI). The DBDI source employed here is characterized by its unique geometry, being directly mounted onto the inlet capillary of a mass spectrometer. In the literature, this particular kind of DBDI source is also referred to as active capillary plasma ionization. It has been commercialized as soft ionization by chemical reaction in transfer (SICRIT) and will be addressed as DBDI in this study. LA-DBDI-MS was used for the direct, molecule-specific and spatially resolved analysis of various solid samples, such as coffee beans and pain killer tablets without extensive sample preparation. The combination of fast washout UV-laser ablation and the principle of the DBDI source used here allowed for highly efficient soft ionization as well as high spatial resolution down to 10 μm for molecular imaging., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Markus Weber and Dr. Jan-Christoph Wolf both are employees of Plasmion GmbH, who is the developer and manufacturer of the SICRIT ion source used within this study., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Due to the much lower production costs but similar effects to lysergic acid diethylamide (LSD), phenethylamine derivatives are sold as a cheaper replacement or deceptively as LSD itself. These potent hallucinogenic substances can lead to severe intoxication, thus a more profound understanding of their use is required. This includes the elucidation of the manufacturing processes for the commonly used blotter papers and the assessment of the risk of overdosing because of a heterogeneous distribution on the blotter papers. Besides the rapid detection of the analytes, the manufacturing process was elucidated by three different imaging techniques and liquid chromatography-mass spectrometry (LC-MS). A blotter paper sample, containing the two hallucinogenic phenethylamine derivatives 25I-NBOMe and 25C-NBOMe, was analyzed by complementary techniques such as micro x-ray fluorescence (μXRF), laser ablation (LA)-inductively coupled plasma-optical emission spectroscopy (ICP-OES), matrix assisted laser desorption ionization (MALDI)-MS, and with LC-MS after extraction. Using the signal from chlorine and iodine within the compounds, μXRF proved to be the fastest, cheapest and easiest method for identification, requiring no sample preparation at all. LA-ICP-OES provided three-dimensional information of the elements in the blotter paper. These results helped to confirm the assumption that manufacturers spray the compounds onto the paper. Whereas μXRF and LA-ICP-OES detected signals for chlorine and iodine, MALDI-MS-imaging showed the molecular distribution of both analytes. LC-MS analyses as a complementary method support the imaging results. Quantitative results for different drug hotspots revealed a heterogeneous distribution of the drugs on the blotter paper implying an inherent risk of overdosing for consumers., (© 2019 The Authors. Drug Testing and Analysis published by John Wiley & Sons Ltd.)

A careful separation, identification and characterization of polymer-coated quantum dots (P-QDs) in complex media such as soil solution is the key point to understand their behaviour and to accurately predict their fate in the environment. In the present study, a synthesized CdSe/ZnS core/shell P-QDs suspension, proved to be stable for at least six months, was investigated with respect to P-QDs dimension, structure and elemental composition. Separation of P-QDs and size distribution determination were carried out by Asymmetric Flow Field-Flow Fractionation (AF4) - Multi Angle Light Scattering (MALS). AF4 and MALS were coupled to Inductively Coupled Plasma-Mass Spectrometry (ICPMS) as a selective and sensitive technique for the detection and the characterization of metallic and metalloid analytes. The exploration of element-specific data obtained by ICPMS after AF4 separation enabled the signal to be deconvoluted reliably. Thus, 3 classes of size populations were identified from the whole population of P-QDs. Additionally, a soil solution and a mix of P-QDs suspension with soil solution were characterized by the same method. This strategy enabled the P-QD population, which interacted with the soil solution, to be determined, this interaction leading either to an aggregation or dissolution of the P-QDs. Reproducibility and recovery of the size distributions and element concentrations were examined for each sample. Complementarily, Dynamic Light Scattering (DLS) and Scanning Transmission Electron Microscopy (STEM) were used jointly with AF4-MALS-ICPMS in order to demonstrate all potentialities of this coupling technique., (Copyright © 2018 Elsevier B.V. All rights reserved.)