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Non-target analysis (NTA) employing high-resolution mass spectrometry is a commonly applied approach for the detection of novel chemicals of emerging concern in complex environmental samples. NTA typically results in large and information-rich datasets that require computer aided (ideally automated) strategies for their processing and interpretation. Such strategies do however raise the challenge of reproducibility between and within different processing workflows. An effective strategy to mitigate such problems is the implementation of inter-laboratory studies (ILS) with the aim to evaluate different workflows and agree on harmonized/standardized quality control procedures. Here we present the data generated during such an ILS. This study was organized through the Norman Network and included 21 participants from 11 countries. A set of samples based on the passive sampling of drinking water pre and post treatment was shipped to all the participating laboratories for analysis, using one pre-defined method and one locally (i.e. in-house) developed method. The data generated represents a valuable resource (i.e. benchmark) for future developments of algorithms and workflows for NTA experiments. © 2021, The Author(s).

This study investigated the environmental contamination of groundwater as a consequence of the discharge of treated wastewater into the soil. The investigation focused on a wastewater treatment plant located in an area fractured by karst in the Salento peninsula (Apulia, Italy). Water samples were collected at four sites (raw wastewater, treated wastewater, infiltration trench, and monitoring well), monthly from May to December 2019 (with the exception of August), and were tested for (1) panel of bacteria; (2) enteric viruses; and (3) chemical substances. A gradual reduction in the concentration of bacteria, viruses and contaminants of emerging concern was observed across the profile of soil fissured by karst. All monitored bacteria were absent from the monitoring well, except for Pseudomonas aeruginosa. Pepper mild mottle virus and adenovirus were detected at all sampling sites. Personal care products and X-ray contrast media showed the greatest decrease in concentration from infiltration trench to the monitoring well, while the highest residual concentrations in the monitoring well were found for anticonvulsants (78.5%), antimicrobials (41.3%), and antipsychotic drugs (38.6%). Our results show that parameters provided by current law may not always be sufficient to evaluate the sanitary risk relating to the discharge of treated wastewater to the soil.

Plant-based clean up technologies are gaining popularity as sustainable solutions to contaminated soil remediation. In particular, plant-assisted bioremediation or phyto-assisted bioremediaton exploits the synergistic action between plant root system and natural microorganisms (bacteria and fungi) to remove, convert or contain toxic substances in soil and water. It relies on the use of a selected appropriate plant for stimulating in the rhizosphere (e.g. through root exudates production, oxygen transport) the biodegradation activity of natural soil microorganisms. In this context, a poplar-assisted bioremediation strategy has been applying for three years to a multi-contaminated (PCBs and heavy metals) area in Southern Italy using a specific poplar clone (Monviso). It was chosen thanks to its capabilities previous tested for promoting hexachlorocyclohexane degradation. At selected times (0, 420, 900 days) PCB and heavy metal (HMs: V, Cr, Sn, Pb) concentrations were assessed on soil samples at different depths and distance from tree trunks inside some contaminated plots. Similarly, microbial analyses were performed on soil samples to assess total microbial abundance, cell viability, dehydrogenase activity and the phylogenetic composition of the autochthonous microbial community. Three years after the poplar planting a significant decrease in PCB and HMs concentrations was observed. Currently, the values of all PCBs detected are under the Italian legislation limits in the plots investigated. The microbiological analysis show an overall improvement in soil quality in terms of an increase in microbial abundance, cell viability and organic carbon content in the rhizosphere soil samples. Moreover, the phylogenetic analysis of the microbial community showed a higher percentage of Bacteria in the rhizosphere than in the bulk soil. In particular, a significant increase in Actinobacteria and Alpha-Gamma-Proteobacteria, which include several speciesable to degrade PCBs, was observed. Overall results show that the poplar-assisted bioremediation strategy was able to promote both the persistent organic contaminant degradation and the phytostabilization of the inorganic ones.

Plant-assisted bioremediation, the use of plants to promote the extraction, the sequester or detoxification of pollutants through biological processes is a green, effective, in situ, non intrusive, low cost, aesthetically pleasing and, socially accepted technology to remediate contaminated soil. Potential for plant-assisted bioremediation depends upon the interactions among, soil, contaminants, microorganisms (bacteria and microfungi) and plants occurring in the rhizosphere where, the release of root exudates and oxygen with circadian rhythm can stimulate the biodegradation activity of natural soil microorganisms. This technology has been applying for three years to a multi-contaminated (PCBs and heavy metals) area in Southern Italy using as plant a selected poplar clone (Monviso).