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Biochar (BC) was characterized as a new carbonaceous material for the adsorption of toluene from water. The tested BC was produced from pine wood gasification, and its sorption ability was compared with that of more common carbonaceous materials such as activated carbon (AC). Both materials were characterized in terms of textural features and sorption abilities by kinetic and equilibrium tests. AC and BC showed high toluene removal from water. Kinetic tests demonstrated that BC is characterized by faster toluene removal than AC is. Textural features demonstrated that the porosity of AC is double that of BC. Nevertheless, equilibrium tests demonstrated that the sorption ability of BC is comparable with that of AC, so the materials’ porosity is not the only parameter that drives toluene adsorption. The specific adsorption ability (mg sorbed m−2 of surface) of the BC is higher than that of AC: toluene is more highly sorbed onto the biochar surface. Biochar is furthermore obtained from biomaterial thermally treated for making energy; this also makes the use of BC economically and environmentally convenient compared with AC, which, as a manufactured material, must be obtained in selected conditions for this type of application.

Polar organic chemical integrative samplers (POCIS) have previously been used to monitor alkylphenol (AP) contamination in water and produced water. However, only the sorbent receiving phase of the POCIS (Oasis beads) is traditionally analyzed, thus limiting the use of POCIS for monitoring a range of APs with varying hydrophobicity. Here a "pharmaceutical" POCIS was calibrated in the laboratory using a static renewal setup for APs (from 2-ethylphenol to 4-n-nonylphenol) with varying hydrophobicity (log K between 2.47 and 5.76). The POCIS sampler was calibrated over its 28 day integrative regime and sampling rates (R) were determined. Uptake was shown to be a function of AP hydrophobicity where compounds with log K < 4 were preferentially accumulated in Oasis beads, and compounds with log K > 5 were preferentially accumulated in the PES membranes. A lag phase (over a 24 h period) before uptake in to the PES membranes occurred was evident. This work demonstrates that the analysis of both POCIS phases is vital in order to correctly determine environmentally relevant concentrations owing to the fact that for APs with log K ≤ 4 uptake, to the PES membranes and the Oasis beads, involves different processes compared to APs with log K ≥ 4. The extraction of both the POCIS matrices is thus recommended in order to assess the concentration of hydrophobic APs (log K ≥ 4), as well as hydrophilic APs, most effectively.

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Nowadays porous materials from organic waste, i.e., Biochar (BC), are receiving increased attention for environmental applications. This study adds information on three BCs that have undergone a number of studies in recent years. A Biochar from pine wood, one from rice husk and one from Eupatorium shrubs enriched with Iron, labelled as PWBC, RHBC and EuFeBC respectively, are evaluated for Trichloroethylene (TCE) removal from aqueous solution. Physical-chemical description is performed by SEM-EDS and BET analysis. The decrease of TCE over time follows a pseudo-second order kinetics with increased removal by the PWBC. Freundlich and Langmuir models well fit equilibrium test data. The optimized values of the maximum adsorbed amount, qmax (mg g−1), follows this order 109.41 PWBC > 30.35 EuFeBC > 21.00 RHBC. Fixed-bed columns are also carried out. Best performance is again achieved by PWBC, which operates for a higher number of pore volume, followed by EuFeBC and RHBC. Continuous testing confirms batch studies and makes it possible to evaluate the workability of materials in configurations closer to reality. Results are promising for potential environmental application. In particular, the characterization of several classes of contaminants opens the doors to possible uses in mixed contamination cases.

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Background: The NORMAN Association (https://www.norman-network.com/) initiated the NORMAN Suspect List Exchange (NORMAN-SLE; https://www.norman-network.com/nds/SLE/) in 2015, following the NORMAN collaborative trial on non-target screening of environmental water samples by mass spectrometry. Since then, this exchange of information on chemicals that are expected to occur in the environment, along with the accompanying expert knowledge and references, has become a valuable knowledge base for “suspect screening” lists. The NORMAN-SLE now serves as a FAIR (Findable, Accessible, Interoperable, Reusable) chemical information resource worldwide. Results: The NORMAN-SLE contains 99 separate suspect list collections (as of May 2022) from over 70 contributors around the world, totalling over 100,000 unique substances. The substance classes include per-and polyfluoroalkyl substances (PFAS), pharmaceuticals, pesticides, natural toxins, high production volume substances covered under the European REACH regulation (EC: 1272/2008), priority contaminants of emerging concern (CECs) and regulatory lists from NORMAN partners. Several lists focus on transformation products (TPs) and complex features detected in the environment with various levels of provenance and structural information. Each list is available for separate download. The merged, curated collection is also available as the NORMAN Substance Database (NORMAN SusDat). Both the NORMAN-SLE and NORMAN SusDat are integrated within the NORMAN Database System (NDS). The individual NORMAN-SLE lists receive digital object identifiers (DOIs) and traceable versioning via a Zenodo community (https://zenodo.org/communities/norman-sle), with a total of >40,000 unique views, >50,000 unique downloads and 40 citations (May 2022). NORMAN-SLE content is progressively integrated into large open chemical databases such as PubChem (https://pubchem.ncbi.nlm.nih.gov/) and the US EPA’s CompTox Chemicals Dashboard (https://comptox.epa.gov/dashboard/), enabling further access to these lists, along with the additional functionality and calculated properties these resources offer. PubChem has also integrated significant annotation content from the NORMAN-SLE, including a classification browser (https://pubchem.ncbi.nlm.nih.gov/classification/#hid=101). Conclusions: The NORMAN-SLE offers a specialized service for hosting suspect screening lists of relevance for the environmental community in an open, FAIR manner that allows integration with other major chemical resources. These efforts foster the exchange of information between scientists and regulators, supporting the paradigm shift to the “one chemical, one assessment” approach. New submissions are welcome via the contacts provided on the NORMAN-SLE website (https://www.norman-network.com/nds/SLE/).