In this article, a dataset from a collaborative non-target screening trial organized by the NORMAN Association is used to review the state-of-the-art and discuss future perspectives of non-target screening using high resolution mass spectrometry in water analysis. A total of 18 institutes from 12 European countries analysed an extract of the same water sample collected from the River Danube with either one or both of liquid and gas chromatography coupled with mass spectrometric detection. This article focuses mainly on the use of high resolution screening techniques with target, suspect and non-target workflows to identify substances in environmental samples. Specific examples are given to highlight major challenges such as isobaric and co-eluting substances, dependence on target and suspect lists, formula assignment, the use of retention information and the confidence of identification. Approaches and methods applicable to unit resolution data are also discussed. While most substances were identified using high resolution data with target and suspect screening approaches, some participants proposed tentative non-target identifications. This comprehensive dataset revealed that non-target analytical techniques are already considerably harmonized between the participants, but the data processing remains time-consuming. Although the dream of a "fully-automated identification workflow" remains elusive in the short-term, important steps in this direction have been taken, exemplified in the growing popularity of suspect screening approaches. Major recommendations to improve non-target screening include better integration and connection of desired features into software packages, the exchange of target and suspect lists and the contribution of more spectra from standard substances into (openly accessible) databases.
Laboratory tests were carried out with three types of new epoxy resins to assess the release of bisphenol A and F (BPA and BPF) and potential halogenated phenolic by-products. Tests were carried out over a duration of 6 months in the presence and absence of disinfectants (chlorine and chlorine dioxide) at realistic doses and contact times. None of the three systems exhibited Fickian-type diffusion for BPA. Leaching was quite low for two epoxies while the third showed a trend of increasing leaching during the first 5 months of immersion. BPA was only observed in the absence of disinfectant while no BPF was observed under any condition. 2,4,6-trichlorophenol (TCP), a BPA chlorination by-product was sporadically observed in the chlorinated water during the first months of contact. Following discontinuation of the disinfectants, its release was significantly enhanced in the water having been exposed to chlorinated water. Laboratory leaching tests also indicated rapid oxidation of epoxies by chlorine and chlorine dioxide. Analysis of 27 epoxy-coated drinking water storage tanks did not reveal any BPA, BPF or TCP. On the other hand, a large-scale examination of about 200 pipe sections rehabilitated with epoxies during the 1990s led to a high frequency of BPA and BPF detection, sometimes with maximum values around 1 μg/L.
The aims of this work are to evaluate the presence of antibiotics in surface waters in a French water basin, where the presence of livestock is relatively important, and to understand the behaviour of antibiotics in drinking water treatment plants (DWTPs). Two sampling sites were chosen because of their livestock density and the presence of DWTPs in areas where urban activities are different. A large range of veterinary and human antibiotics were analysed in raw and treated water from the French Seine-Normandy Basin, based on the development of two analytical methodologies using solid-phase extraction and high-performance liquid chromatography-mass spectrometry. Clorsulon (an anthelmintic), fluoroquinolones, macrolides, sulfonamides (such as sulfamethoxazole, sulfadiazine), tetracyclines and trimethoprim were detected in raw surface water. Regarding the efficiency of drinking water treatment, an ozone/granular activated carbon combination proved to be effective in removing most antibiotics except danofloxacin and enrofloxacin which have an ionisable character and insufficient ozonation kinetic constant. Chlorination proved to be ineffective in removing antibiotics passing through the previous stages.
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