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Little is known about the presence of organic pollutants in human brain (and even less in brain tumors). In this regard, it is necessary to develop new analytical protocols capable of identifying a wide range of exogenous chemicals in this type of samples (by combining target, suspect and non-target strategies). These methodologies should be robust and simple. This is particularly challenging for solid samples, as reliable extraction and clean-up techniques should be combined to obtain an optimal result. Hence, the present study focuses on the development of an analytical methodology that allows the screening of a wide range of organic chemicals in brain and brain tumor samples. This protocol was based on a solid-liquid extraction based on bead beating, solid-phase extraction clean-up with multi-layer mixed-mode cartridges, reconstitution and LCHRMS analysis. To evaluate the performance of the extraction methodology, a set of 66 chemicals (e.g., pharmaceuticals, biocides, or plasticizers, among others) with a wide range of physicochemical properties was employed. Quality control parameters (i.e., linear range, sensitivity, matrix effect (ME%), and recoveries (R%)) were calculated and satisfactory results were obtained for them (e.g., R% within 60–120% for 32 chemicals, or ME% higher than 50% (signal suppression) for 79% of the chemicals).

A collaborative trial involving 16 participants from nine European countries was conducted within the NORMAN network in efforts to harmonise suspect and non-target screening of environmental contaminants in whole fish samples of bream (Abramis brama). Participants were provided with freeze-dried, homogenised fish samples from a contaminated and a reference site, extracts (spiked and non-spiked) and reference sample preparation protocols for liquid chromatography (LC) and gas chromatography (GC) coupled to high resolution mass spectrometry (HRMS). Participants extracted fish samples using their in-house sample preparation method and/or the protocol provided. Participants correctly identified 9–69 % of spiked compounds using LC-HRMS and 20–60 % of spiked compounds using GC-HRMS. From the contaminated site, suspect screening with participants’ own suspect lists led to putative identification of on average ∼145 and ∼20 unique features per participant using LC-HRMS and GC-HRMS, respectively, while non-target screening identified on average ∼42 and ∼56 unique features per participant using LC-HRMS and GC-HRMS, respectively. Within the same sub-group of sample preparation method, only a few features were identified by at least two participants in suspect screening (16 features using LC-HRMS, 0 features using GC-HRMS) and non-target screening (0 features using LC-HRMS, 2 features using GC-HRMS). The compounds identified had log octanol/water partition coefficient (KOW) values from −9.9 to 16 and mass-to-charge ratios (m/z) of 68 to 761 (LC-HRMS and GC-HRMS). A significant linear trend was found between log KOW and m/z for the GC-HRMS data. Overall, these findings indicate that differences in screening results are mainly due to the data analysis workflows used by different participants. Further work is needed to harmonise the results obtained when applying suspect and non-target screening approaches to environmental biota samples.

Prenatal exposure to certain organic chemicals like pesticides and phenols has been lifelong associated with birth outcomes and health disorders. Many personal care product (PCP) ingredients have similar properties or structures to those chemicals. Previous studies have documented the occurrence of UV filters (UVFs) and paraben preservatives (PBs) in the placenta, but observational studies concerning PCPs chemicals and foetal exposure are particularly scarce. Thus, this work aimed to assess the presence of a wide range of PCPs chemicals using target and suspect screening in the umbilical cord blood of new born babies to evaluate their potential transfer to the fetus. To do so, we analysed 69 umbilical cord blood plasma samples from a mother–child cohort from Barcelona (Spain). We quantified 8 benzophenone-type UVFs and their metabolites, and 4 PBs using validated analytical methodologies based on target screening using liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Then, we screened for additional 3246 substances using high-resolution mass spectrometry (HRMS) and advanced suspect analysis strategies. Six UVFs and three parabens were detected in the plasma with frequencies between 1.4% and 17.4% and concentrations up to 53.3 ng/mL (benzophenone-2). Thirteen additional chemicals were tentatively identified in the suspect screening, and ten were further confirmed with the corresponding standards. Among them, we found the organic solvent N-methyl-2-pyrrolidone, the chelating agent 8-hydroxyquinoline, and the antioxidant 2,2′-methylenebis(4-methyl-6-tert-butylphenol), which have been demonstrated to display reproductive toxicity. UVFs and PBs presence in the umbilical cord blood demonstrates mother-fetus transfer through the placental barrier and prenatal exposure to these PCPs chemicals, which may lead to adverse effects in the early stages of fetal development. Considering the small cohort used in this study, the reported results should be interpreted as a preliminary reference for the background umbilical cord transfer levels of the target PCPs chemicals. Further research is needed to determine the long-term consequences of prenatal exposure to PCPs chemicals.