Rationale Chlorinated paraffins (CPs) are a group of anthropogenic pollutants that consist of complex mixtures of polychlorinated n‐alkanes of different chain lengths (~C10 to C30). Persistence, bioaccumulation, toxicity, and long‐range transport of short‐chain chlorinated paraffins (SCCPs, C10‐ to C13‐CPs) have prompted their classification as persistent organic pollutants (POPs) by the Stockholm Convention in 2017. Due to the varying chain lengths and chlorination degrees, quantification of SCCPs and medium‐chain chlorinated paraffins (MCCPs, C14‐ to C17) using gas chromatography coupled with electron capture negative ion mass spectrometry in selected ion monitoring mode (GC/ECNI‐MS‐SIM) is not only challenging but also very time consuming. In particular, up to eight GC runs per sample are required for the comprehensive GC/ECNI‐MS‐SIM quantification of SCCPs and MCCPs. These efforts are high especially if the samples do not contain CPs above the limit of detection (LOD), subsequently. Methods We developed a semi‐quantitative and sensitive method for the examination of SCCPs and MCCPs in one GC run. This GC/ECNI‐MS‐SIM screening method was based on the recording of Cl− (m/z 35 and 37), Cl2− (m/z 70 and 72), and HCl2− (m/z 71 and 73) isotope ions and evaluation of the ratios between them. Results Correctness of the results of the screening method was verified by analysis of edible oils with and without CPs, CP standards, as well as a technical CP mixture. Polychlorinated biphenyls (PCBs) and other polyhalogenated aromatic compounds, as well as brominated flame retardants, do not form all of the fragment ions analyzed by the screening method. Conclusions After the screening, only CP‐positive samples may need to be measured in detail. Measurement time will already be gained in the case of ~10% samples without CPs.

A variety of vitamin E dietary supplement capsules (DSC) based on different natural oils or synthesis products are currently found on the market whose vitamin contents need to be controlled before and after marketing. Here, we present an instrumental thin-layer chromatography (TLC) method which allows a direct determination of all tocopherols (T) and tocotrienols (T3) as well as α-tocopherol acetate simultaneously in one run with short analysis time. For this purpose, contents of the DSC were extracted, applied on silica gel 60 plates, and developed with n-hexane/ethyl acetate/acetic acid, 90:10:2 (v/v/v) as mobile phase. The UV scan of the plate at 293 nm was used for quantification based on the peak height. Following the scan, the plate was treated with 10% sulphuric acid in methanol which led to characteristic yellow-to-brown colouring of the tocochromanol spots which allowed to distinguish tocochromanols from matrix components with similar Rf values. In most cases, determined vitamin E contents matched well with the information listed on the label of the investigated DSC samples. The method is fast, easy to perform and gently treats the analytes as it requires no thermal treatment prior to quantification, which makes it suitable as a screening method.

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