14 research outputs found

    Water taste and odor (T&O): Challenges, gaps and solutions from a perspective of the WaterTOP network

    Get PDF
    Aesthetic aspects of drinking water, such as Taste and Odor (T&O), have significant effects on consumer perceptions and acceptability. Solving unpleasant water T&O episodes in water supplies is challenging, since it requires expertise and know-how in diagnosis, evaluation of impacts and implementation of control measures. We present gaps, challenges and perspectives to advance water T&O science and technology, by identifying key areas in sensory and chemical analysis, risk assessment and water treatment, as articulated by WaterTOP (COST Action CA18225), an interdisciplinary European and international network of researchers, experts, and stakeholders

    Seasonal dynamics of freshwater pathogens as measured by microarray at Lake Sapanca, a drinking water source in the north-eastern part of Turkey

    No full text
    Monitoring drinking water quality is an important public health issue. Two objectives from the 4 years, six nations, EU Project μAqua were to develop hierarchically specific probes to detect and quantify pathogens in drinking water using a PCR-free microarray platform and to design a standardised water sampling programfrom different sources in Europe to obtain sufficient material for downstream analysis. Our phylochip contains barcodes (probes) that specifically identify freshwater pathogens that are human health risks in a taxonomic hierarchical fashion such that if species is present, the entire taxonomic hierarchy (genus, family, order, phylum, kingdom) leading to it must also be present, which avoids false positives. Molecular tools are more rapid, accurate and reliable than traditional methods, which means fastermitigation strategies with less harm to humans and the community.We present microarray results for the presence of freshwater pathogens from a Turkish lake used drinking water and inferred cyanobacterial cell equivalents from samples concentrated from 40 into 1 L in 45 min using hollow fibre filters. In two companion studies from the same samples, cyanobacterial toxins were analysed using chemical methods and those dates with highest toxin values also had highest cell equivalents as inferred from this microarray study

    A validated UPLC–MS/MS method for the surveillance of ten aquatic biotoxins in European brackish and freshwater systems

    No full text
    Over the past few decades, there has been an increased frequency and duration of cyanobacterial Harmful Algal Blooms (HABs) in freshwater systems globally. These can produce secondary metabolites called cyanotoxins, many of which are hepatotoxins, raising concerns about repeated exposure through ingestion of contaminated drinking water or food or through recreational activities such as bathing/swimming. An ultra-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) multi-toxin method has been developed and validated for freshwater cyanotoxins; microcystins-LR, -YR, -RR, -LA, -LY and -LF, nodularin, cylindrospermopsin, anatoxin-a and the marine diatom toxin domoic acid. Separation was achieved in around 9 min and dual SPE was incorporated providing detection limits of between 0.3 and 5.6 ng/L of original sample. Intra- and inter-day precision analysis showed relative standard deviations (RSD) of 1.2–9.6% and 1.3–12.0% respectively. The method was applied to the analysis of aquatic samples (n = 206) from six European countries. The main class detected were the hepatotoxins; microcystin-YR (n = 22), cylindrospermopsin (n = 25), microcystin-RR (n = 17), micro- cystin-LR (n = 12), microcystin-LY (n = 1), microcystin-LF (n = 1) and nodularin (n = 5). For microcystins, the levels detected ranged from 0.001 to 1.51 mg/L, with two samples showing combined levels above the guideline set by the WHO of 1 mg/L for microcystin-LR. Several samples presented with multiple toxins indicating the potential for synergistic effects and possibly enhanced toxicity. This is the first published pan European survey of freshwater bodies for multiple biotoxins, including two identified for the first time; cylindrospermopsin in Ireland and nodularin in Germany, presenting further incentives for improved monitoring and development of strategies to mitigate human exposure

    Monitoring of freshwater toxins in European environmental waters by using novel multi-detection methods.

    Get PDF
    Monitoring the quality of freshwater is an important issue for public health. In samples were collected from several waters in France, Germany, Ireland, Italy, multitoxin detection methods previously developed: a microsphere-based liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) method. cylindrospermopsin, and several analogues of anatoxin-a (ATX-a) was found in any of the environmental samples. Microcystin-LR and microcystin- In the case of ATX-a derivatives, 75% of samples contained mainlyH2-ATX-a and homoanatoxin-a were found in only 1 sample. These results confirm the ATX-a toxins in European freshwaters

    Cation‐Site Disordered Cu3_3PdN Nanoparticles for Hydrogen Evolution Electrocatalysis

    No full text
    Transition metal nitrides (TMNs) are emerging as a promising class of materials for application in optoelectronics as well as energy conversion and storage, but they remain rather unexplored, mainly due to a lack of mechanistic understanding of their synthetic pathways. Here, a one-pot synthesis is demonstrated, which yields 3 nm phase-pure Cu3_3PdN nanoparticles after the reaction of Cu methoxide and Pd acetylacetonate in benzylamine for 5 min at 140 °C. The structure of the initial complexes and their conversion to Cu3_3PdN are revealed by in situ X-ray absorption spectroscopy measurements and elucidate nucleation and growth of the nitride nanocrystals by in situ total X-ray scattering measurements. Interestingly, extended X-ray absorption fine structure double-edge refinement reveals the presence of short-range cation-site disorder in the anti-perovskite structure of Cu3PdN, which has not been observed before in the Cu3PdN system. Additionally, the synthesized Cu3PdN nanoparticles are tested for the electrocatalytic hydrogen evolution reaction, revealing an overpotential as low as η10η_{10} = 212 ± 11 mV measured at 10 mA cm2^{−2}

    Utilizing High X-ray Energy Photon-In Photon-Out Spectroscopies and X-ray Scattering to Experimentally Assess the Emergence of Electronic and Atomic Structure of ZnS Nanorods

    No full text
    The key to controlling the fabrication process of transition metal sulfide nanocrystals is to understand the reaction mechanism, especially the coordination of ligands and solvents during their synthesis. We utilize in situ high-energy resolution fluorescence detected X-ray absorption spectroscopy (HERFD-XAS) as well as in situ valence-to-core X-ray emission spectroscopy (vtc-XES) combined with density functional theory (DFT) calculations to identify the formation of a tetrahedral [Zn(OA)4_4]2+^{2+} and an octahedral [Zn(OA)6_6]2+^{2+} complex, and the ligand exchange to a tetrahedral [Zn(SOA)4_4]2+^{2+} complex (OA = oleylamine, OAS = oleylthioamide), during the synthesis of ZnS nanorods in oleylamine. We observe in situ the transition of the electronic structure of [Zn(SOA)4_4]2+^{2+} with a HOMO/LUMO gap of 5.0 eV toward an electronic band gap of 4.3 and 3.8 eV for 1.9 nm large ZnS wurtzite nanospheres and 2 × 7 nm sphalerite nanorods, respectively. Thus, we demonstrate how in situ multimodal X-ray spectroscopy and scattering studies can not only resolve structure, size, and shape during the growth and synthesis of NPs in organic solvents and at high temperature but also give direct information about their electronic structure, which is not readily accessible through other techniques
    corecore