72 research outputs found

    Accumulation of Phycotoxins in the Mussel Mytilus galloprovincialis from the Central Adriatic Sea

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    Surveys of DSP (Diarrheic Shellfish Poisoning) toxin profiles in the mussel Mytilus galloprovincialis from coastal waters of the central Adriatic Sea, over the years 1995 to 2001, demonstrate that incidents of shellfish toxicity in this area are dominated by the occurrence of okadaic acid (OA) and a PTX derivative, 7-epi-pectenotoxin-2-seco acid (7-epi-PTX-2SA). Toxin composition and the relative ratio of toxic components in shellfish is in correlation with the occurrence of DSP producing organisms from the Dinophysis species along with Prorocentrum micans and Lingulodinium polyedrum. The occurrence of D. sacculus shortly before the appearance of OA in shellfish implicates its possible involvement as the source of toxicity. In the central Adriatic, the infestation period generally ranges from June to August. Augmented toxin production may shift the depuration phase to September; however, the length of decontamination period is not in correlation with increased initial toxicity. The mussel M. galloprovincialis may retain contamination with 7-epi-PTX-2SA beyond the commonly recognized infestation period, extending the risk of human poisoning from consumption of seco-contaminated seafood

    Accumulation of Phycotoxins in the Mussel Mytilus galloprovincialis from the Central Adriatic Sea

    Get PDF
    Surveys of DSP (Diarrheic Shellfish Poisoning) toxin profiles in the mussel Mytilus galloprovincialis from coastal waters of the central Adriatic Sea, over the years 1995 to 2001, demonstrate that incidents of shellfish toxicity in this area are dominated by the occurrence of okadaic acid (OA) and a PTX derivative, 7-epi-pectenotoxin-2-seco acid (7-epi-PTX-2SA). Toxin composition and the relative ratio of toxic components in shellfish is in correlation with the occurrence of DSP producing organisms from the Dinophysis species along with Prorocentrum micans and Lingulodinium polyedrum. The occurrence of D. sacculus shortly before the appearance of OA in shellfish implicates its possible involvement as the source of toxicity. In the central Adriatic, the infestation period generally ranges from June to August. Augmented toxin production may shift the depuration phase to September; however, the length of decontamination period is not in correlation with increased initial toxicity. The mussel M. galloprovincialis may retain contamination with 7-epi-PTX-2SA beyond the commonly recognized infestation period, extending the risk of human poisoning from consumption of seco-contaminated seafood

    Monitoring criteria for priority chemicals leading to emission factors

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    The Water Framework Directive (WFD) 2000/60/EC, requires a coordinated approach to water management in respect of whole river basins with a view to protecting the high-status of waters where it exists, preventing any deterioration in the existing status of waters and achieving at least "good status" in relation to all waters. The EPA-funded Monitoring Criteria for Priority Chemicals Leading to Emission Factors aims to establish risk factors for priority substances (PS) & priority hazardous substances (PHS), which will assist in defining the monitoring programme in Ireland for WFD. Indicators are applied to monitored WWTP agglomerations to predict the relative risk of elevated PS/PHS loading to receiving waters across agglomerations over time. In Ireland, where the current state of knowledge and data availability (e.g. emission data from individual installations) is insufficient to support high resolution based models the project team have developed a simple, stochastic, risk-based model that can be applied across catchments to predict the relative risk of elevated PS/PHS loading to receiving water

    Accumulation of Phycotoxins in the Mussel Mytilus galloprovincialis from the Central Adriatic Sea

    Get PDF
    Surveys of DSP (Diarrheic Shellfish Poisoning) toxin profiles in the mussel Mytilus galloprovincialis from coastal waters of the central Adriatic Sea, over the years 1995 to 2001, demonstrate that incidents of shellfish toxicity in this area are dominated by the occurrence of okadaic acid (OA) and a PTX derivative, 7-epi-pectenotoxin-2-seco acid (7-epi-PTX-2SA). Toxin composition and the relative ratio of toxic components in shellfish is in correlation with the occurrence of DSP producing organisms from the Dinophysis species along with Prorocentrum micans and Lingulodinium polyedrum. The occurrence of D. sacculus shortly before the appearance of OA in shellfish implicates its possible involvement as the source of toxicity. In thecentral Adriatic, the infestation period generally ranges from June to August. Augmented toxin production may shift the depuration phase to September; however, the length of decontamination period is not in correlation with increased initial toxicity. The mussel M. galloprovincialis may retain contamination with 7-epi-PTX-2SA beyond the commonly recognized infestation period, extending the risk of human poisoning from consumption of seco-contaminated seafood

    Antifungal activity of Lactobacillus against Microsporum canis, Microsporum gypseum and Epidermophyton floccosum

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    A total of 220 lactic acid bacteria isolates were screened for antifungal activity using Aspergillus fumigatus and Aspergillus niger as the target strains. Four Lactobacillus strains exhibited strong inhibitory activity on agar surfaces. All four were also identified as having strong inhibitory activity against the human pathogenic fungi Microsporum canis, Microsporum gypseum and Epidermophyton floccosum. One of the four lactobacilli, namely Lb. reuteri ee1p exhibited the most inhibition against dermatophytes. Cell-free culture supernatants of Lb. reuteri ee1p and of the non-antifungal Lb. reuteri M13 were freeze-dried and used to access and compare antifungal activity in agar plate assays and microtiter plate assays. Addition of the Lb. reuteri ee1p freeze-dried cell-free supernatant powder into the agar medium at concentrations greater than 2% inhibited all fungal colony growth. Addition of the powder at 5% to liquid cultures caused complete inhibition of fungal growth on the basis of turbidity. Freeze-dried supernatant of the non-antifungal Lb. reuteri M13 at the same concentrations had a much lesser effect. As Lb. reuteri M13 is very similar to the antifungal strain ee1p in terms of growth rate and final pH in liquid culture, and as it has little antifungal activity, it is clear that other antifungal compounds must be specifically produced (or produced at higher levels) by the anti-dermatophyte strain Lb. reuteri ee1p. Reuterin was undetectable in all four antifungal strains. The cell free supernatant of Lb. reuteri ee1p was analyzed by LC-FTMS using an Accela LC coupled to an LTQ Orbitrap XL mass spectrometer. The high mass accuracy spectrum produced by compounds in the Lb. reuteri ee1p strain was compared with both a multianalyte chromatogram and individual spectra of standard anti-fungal compounds, which are known to be produced by lactic acid bacteria. Ten antifungal metabolites were detected

    Devising a risk index for priority substance emissions from WWTPs

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    A review was used to identify the major factors leading to priority substances (PS) & priority hazardous substances (PHS) loading from WWTPs, integrated and conceptualised into a basic conceptual model. The focus is on readily-available data relevant to major PS/PHS risk factors identified by conceptual modelling, developing appropriate indicators. Databases were compiled for Local Authority and EPA licensed discharges, and agglomeration traffic. Results from these databases were integrated into the risk model for agglomeration PS/PHS loading, combined with basic WWTP (e.g. capacity and treatment level) and agglomeration (e.g. population and area) data, and finally expressed as elevated risk in a national context following normalisation procedures

    Licensing & treatment variability among WWTPs in the monitoring criteria for priority chemicals leading to emission factors project

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    A system for the licensing of waste water discharges from areas served by local authority sewer networks was introduced in 2007 and will require all WWTP to obtain a waste water discharge licence from the EPA by set dates depending on the population equivalent (PE) of the area served by the sewer network. The licensing gives effect to a number of EU Directives, imposing restrictions or prohibitions on the discharge of dangerous substances to receiving water bodies

    Priority and hazardous substances

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    The EU Water Framework Directive (WFD) (2000/60/EC) was transposed into Irish law in 2003 as the European Communities (Water Policy) The level of priority substances present in water bodies is most commonly judged against set environmental quality standards (EQSs) . These standards dictate the maximum allowable concentrations (MAC EQS) or range of concentrations (Annual Average or AA EQS) of specific pollutants allowed to ensure compliance with the EC guidelines. The EU WFD was transposed into Irish Law in 2003 and as such these EQS values now form the basis of priority substance water monitoring in Ireland

    Transparent polymer-based SERS substrates templated by a soda can

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    This paper demonstrates the reproducible fabrication of transparent Surface Enhanced Raman Scattering (SERS) substrates, fabricated by employing an aluminium soda can to template nanostructures on a flexible thermoplastic polymer surface, followed by deposition of a silver over layer. Electron microscopy and finite element modelling simulations strongly suggested the SERS response arose at regions of high electromagnetic field strength occurring between metallic clusters following illumination by monochromatic radiation. The sensors exhibited rapid, quantitative and high sensitivity, for example, 5 × 10−10 M (204 pg/mL) crystal violet detection in 10 min using a simple drop and dry method. We also show detection of glucose employing a chemically modified silver surface bearing a pre-deposited SAM layer. Furthermore, the transparent substrates permitted back excitation and collection through the substrate with corresponding spectra exhibiting clear and well-defined spectral SERS peaks. Finally, we present the detection of trace amounts of melamine in complex media solution (milk and infant formula). We benchmark the sensor performance using commercial analytical instrumentation (MS-MS) and show comparable sensitivity between the SERS substrates and MS-MS
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