The fish farm of origin is assigned by the element profile of Atlantic salmon (Salmo salar L.) scales in a simulated escape event

Publication date: October 2018
Source:Fisheries Research, Volume 206
Author(s): Belinda Flem, Tonje Fagertun Benden, Tor Erik Finne, Vidar Moen, Thor Mikkel Nordahl, Ketil Skår, Øystein Nordgulen, Arne Solli
The Norwegian aquaculture management authorities require that the sea farm of origin for escaped salmon can be identified. As a contribution to develop a reliable and feasible method for tracing escaped salmon to their sea cage of origin the proof-of-concept of the case-based red alert method 'FarmSalmTrack' is demonstrated through a simulated escape event. The 'FarmSalmTrack' method uses the trace element distribution in the scale hydroxyapatite, HAP-layer, to discriminate between groups of salmon. The case-based approach can primarily be used for larger escapes and preferably where the escaped fish are caught relatively soon after the time of escape. The method is dependent on baseline data being available from all sea farm cages potentially responsible for the escape. Classification of the escapees towards the baseline material collected from nearby sea cages holding salmon of same age and size is done in a three-step process; (1) analysis of the Sr/Ba ratio which reveals if seawater or salt are added to the hatchery tanks, (2) analysis of element profiles in the juvenile section of the scale and (3) analysis of trace element profile of the scale HAP-layer formed in seawater. Step (1) reduced the number of suspected sea cages by one half, step (2) identified the escapees' hatchery of origin and step (3) identified the sea cage of origin. The classification was based on the concentration of the elements B, Ba, Li, Mg, Mn, Na, S, Sr, U and Zn along selected sclerites. Barium was the most important element for correct classification using the elemental profile of the juvenile section of the scale, while Zn showed the strongest influence on the classification using the seawater section of the scale. Improved understanding of the incorporation of non-essential life elements and essential life elements into the bio-mineralised structures of the fish scale HAP-layer would be highly beneficial for further development of the 'FarmSalmTrack-method'.



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Multi-element composition of red, white and palhete amphora wines from Alentejo by ICPMS

Publication date: October 2018
Source:Food Control, Volume 92
Author(s): Maria João Cabrita, Nuno Martins, Pedro Barrulas, Raquel Garcia, Cristina Barrocas Dias, Eva P. Pérez-Álvarez, Ana Maria Costa Freitas, Teresa Garde-Cerdán
Amphora wines also known as Vinhos de Talha are typical of Alentejo, in the south of Portugal. Crushed berries are fermented in clay vessels, regardless being white, red or a mixture of both grapes, with a minimalist intervention, resulting in white, red or palhete wines. Due to the technological differences associated to the winemaking process of these wines, the present research aimed to evaluate the mineral characterization of amphora wines with the purpose of ensuring consumer food safety and exploring the possibility of using mineral composition to establish the geographic origin of the wines. Red, white and palhete amphora wines from Vidigueira, Vila Alva, Vila de Frades and Cuba (Alentejo region) were studied. Inductively coupled plasma mass spectrometry (ICPMS) was used and the concentration of 30 elements was determined. Data shows differences among red, white and palhete wines regarding the multi-element composition, and linear discriminant analysis allowed a classification according to the wine type and geographic origin. From all samples, only one red wine presented concentrations of Zn higher than the value published by International Organisation of Vine and Wine (OIV, 2015).



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Ocean acidification modulates the incorporation of radio-labeled heavy metals in the larvae of the Mediterranean sea urchin Paracentrotus lividus

Publication date: October 2018
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): Narimane Dorey, Sophie Martin, François Oberhänsli, Jean-Louis Teyssié, Ross Jeffree, Thomas Lacoue-Labarthe
The marine organisms which inhabit the coastline are exposed to a number of anthropogenic pressures that may interact. For instance, the accumulation of toxic metals present in coastal waters is expected to be modified by ocean acidification through e.g. changes in physiological performance and/or elements availability. Changes in bioaccumulation due to lowering pH are likely to be differently affected depending on the nature (essential vs. non-essential) and speciation of each element. The Mediterranean is of high concern for possible cumulative effects due to strong human influences on the coastline.The aim of this study was to determine the effect of ocean acidification (from pH 8.1 down to −1.0 pH units) on the incorporation kinetics of six trace metals (Mn, Co, Zn, Se, Ag, Cd, Cs) and one radionuclide (²⁴¹Am) in the larvae of an economically- and ecologically-relevant sea urchin of the Mediterranean coastline: Paracentrotus lividus. The radiolabelled metals and radionuclides added in trace concentrations allowed precise tracing of their incorporation in larvae during the first 74 h of their development.Independently of the expected indirect effect of pH on larval size/developmental rates, Paracentrotus lividus larvae exposed to decreasing pHs incorporated significantly more Mn and Ag and slightly less Cd. The incorporation of Co, Cs and ²⁴¹Am was unchanged, and Zn and Se exhibited complex incorporation behaviors. Studies such as this are necessary prerequisites to the implementation of metal toxicity mitigation policies for the future ocean. We discuss possible reasons and mechanisms for the specific effect of pH on each metals.

Graphical abstract

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Formation and characterization of one-dimensional ZnS nanowires for ZnS/P3HT hybrid polymer solar cells with improved efficiency

Publication date: 1 September 2018
Source:Applied Surface Science, Volume 451
Author(s): Katarzyna Matras-Postołek, Adam Żaba, Elżbieta M. Nowak, Paweł Dąbczyński, Jakub Rysz, Jerzy Sanetra
Photovoltaic performance of hybrid devices consisting of zinc sulphide (ZnS) one-dimensional (1D) nanowires and P3HT polymer was studied. As we previously reported, hybrid solar cell architecture based on ZnS, where open circuit voltage reaches high value, deserves special attention. In this work, compared to our previous research, zero-dimensional (0D) ZnS nanoparticles were replaced by one-dimensional (1D) ZnS nanowires synthesized simply with a hot injection method. In order to improve the charge transport in hybrid solar cells, additionally, the initial ligand of octadecylamine (ODA) was partially replaced by the o-phenylenediamine. The as-synthesized products were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–vis spectroscopy, photoluminescence (PL) spectroscopy, energy dispersive spectroscopy (EDS), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. The performance of the devices significantly depended on the concentration of one-dimensional ZnS nanowires incorporated in the active layer (optimal 10 wt.%) and their morphology. In the presented work, we showed that devices based on 1D ZnS nanowires were distinguished by the high value of Voc parameter (with the maximum achieved value of 0.634 V). Also we investigated the spatial layout of nanocrystals in the device, depending on its post treatment, using atomic force microscopy (AFM), time-of-flight secondary ion mass spectrometry (TOF-SIMS) and ultraviolet photoelectron spectroscopy (UPS). Our study showed spatial segregation of nanocrystals to both interfaces with electrodes, and also we showed significant changes (0.71 eV at the top) in the PEDOT:PSS work function after mixing with ZnS nanocrystals, which resulted in an increase in the difference in contact potential at respective electrodes, which explained the high value of Voc. In comparison to our previous study, by replacing an active layer of the 0D ZnS nanocrystals with 1D ZnS nanowires, nearly a triple increase of the overall efficiency (maximum of % η of 0.568) of the device was observed.

Graphical abstract

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Stress response of Triticum aestivum L. and Brassica juncea L. against heavy metals growing at distillery and tannery wastewater contaminated site

Publication date: September 2018
Source:Chemosphere, Volume 206
Author(s): Pankaj Chowdhary, Ashutosh Yadav, R. Singh, Ram Chandra, D.P. Singh, Abhay Raj, Ram Naresh Bharagava
This study aimed to investigate the effects of potentially toxic elements on biochemical parameters in wheat (Triticum aestivum L.) and mustard (Brassica juncea L.) plants growing at distillery and tannery wastewater contaminated sites. The analysis of plants showed the highest accumulation of Fe (361 mg kg⁻¹ in wheat root and 359 mg kg⁻¹ in mustard leaves) followed by Zn, Cr and Mn in leaf>shoot>root. Further, the Chl-a, b, and carotenoids content was also found high in plant samples. Results also showed that photosynthetic content in wheat and mustard growing at tannery wastewater contaminated sites was Chl-a 3.92, 4.53 (mg g^_1 fw), Chl-b 2.39, 1.29 (mg g^_1 fw) and carotenoids 0.28, 0.32 (mg g^_1 fw), respectively. Whereas, photosynthetic content in these plants with distillery waste was as Chl-a 3.43, 4.88 (mg g^_1 fw), Chl-b 1.12, 2.05 (mg g^_1 fw) and carotenoids 0.24, 0.29 (mg g^_1 fw), respectively. In addition, the activity of plant enzymes such as SOD, APx, GPX, MDA, H2O2, and CAT was also higher in selected plants in comparison to control plants. Moreover, the high bioconcentration factor of Zn > 1 (1.29) and translocation factor >10 (10.31) of Cr in tannery wastewater affected mustard plants. This study concluded that industrial wastewaters are the primary sources of metal accumulation in agricultural crops and thus, it should not be discharged into the environment before its proper treatment. Hence, the continuous monitoring of sludge/soil, agricultural plants and water quality are imperative for the impediment of possible health hazards to animal and human beings.

Graphical abstract

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Photocatalytic hydrogen production from glycerol solution at room temperature by ZnO-ZnS/graphene photocatalysts

Publication date: 1 September 2018
Source:Applied Surface Science, Volume 451
Author(s): Chi-Jung Chang, Yan-Gu Lin, Hau-Ting Weng, Yi-Hung Wei
Glycerol is a byproduct of biodiesel manufacturing. The room temperature photocatalytic hydrogen generation from glycerol by the ZnO-ZnS/graphene photocatalyst was investigated. The in-situ C K-edge near edge X-ray absorption fine structure (NEXAFS) spectra were measured with/without light illumination to study the electronic properties of photocatalysts at atomic and molecular level. A mechanism of water splitting and glycerol oxidation/reforming reactions over the photocatalyst under light irradiation is proposed. Effects of graphene content in photocatalysts and glycerol concentration in solution on the photocatalytic activity were examined. The results of enhanced photocurrents, fluorescence quenching, NEXAFS spectra, and decreased arc radius of electrochemical impedance spectra of ZnO-ZnS/graphene photocatalysts revealed the fast transfer of photoexcited electrons from ZnO-ZnS nanoparticles to graphene. There was an optimal graphene content and a glycerol concentration for the maximum photocatalytic H2 production rate (1070 μmol h⁻¹ g⁻¹). Incorporation of graphene can enhance the separation of photogenerated charge through the ZnO-ZnS/graphene interfaces and improve the photocatalytic H2 production rate of the photocatalysts. The composite photocatalysts exhibited improved performance because of efficient charge separation and enhanced light absorption.

Graphical abstract

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Environmental risk of severely Pb-contaminated riverbank sediment as a consequence of hydrometeorological perturbation

Publication date: 15 September 2018
Source:Science of The Total Environment, Volume 636
Author(s): S.F.L. Lynch, L.C. Batty, P. Byrne
Metal mining activities have resulted in the widespread metal pollution of soils and sediments and are a worldwide health concern. Pb is often prolific in metal-mining impacted systems and has acute and chronic toxic effects. Environmental factors controlling diffuse pollution from contaminated riverbank sediment are currently seen as a "black box" from a process perspective. This limits our ability to accurately predict and model releases of dissolved Pb. Previous work by the authors uncovered key mechanisms responsible for the mobilisation of dissolved Zn. The current study identifies key mechanisms controlling the mobilisation of dissolved Pb, and the environmental risk these releases pose, in response to various sequences of "riverbank" inundation/drainage. Mesocosm experiments designed to mimic the riverbank environment were run using sediment severely contaminated with Pb, from a mining-impacted site. Results indicated that, although Pb is generally reported as less mobile than Zn, high concentrations of dissolved Pb are released in response to longer or more frequent flood events. Furthermore, the geochemical mechanisms of release for Zn and Pb were different. For Zn, mechanisms were related to reductive dissolution of Mn (hydr)oxides with higher concentrations released, at depth, over prolonged flood periods. For Pb, key mechanisms of release were related to the solubility of anglesite and the oxidation of primary mineral galena, where periodic drainage events serve to keep sediments oxic, particularly at the surface. The results are concerning because climate projections for the UK indicate a rise in the occurrence of localized heavy rainfall events that could increase flood frequency and/or duration. This study is unique in that it is the first to uncover key mechanisms responsible for dissolved Pb mobilisation from riverbank sediments. The mineralogy at the mining-impacted site is common to many sites worldwide and it is likely the mechanisms identified in this study are widespread.

Graphical abstract

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