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Human norovirus detection in bivalve shellfish in Brazil and evaluation of viral infectivity using PMA treatment
2020
Sarmento, Sylvia Kahwage | Guerra, Caroline Rezende | Malta, Fábio Correia | Coutinho, Ricardo | Miagostovich, Marize Pereira | Fumian, Tulio Machado
Noroviruses are the most common cause of gastroenteritis outbreaks in humans and bivalve shellfish consumption is a recognized route of infection. Our aim was to detect and characterize norovirus in bivalves from a coastal city of Brazil. Nucleic acid was extracted from the bivalve's digestive tissue concentrates using magnetic beads. From March 2018 to June 2019, 77 samples were screened using quantitative RT-PCR. Noroviruses were detected in 41.5%, with the GII being the most prevalent (37.7%). The highest viral load was 3.5 × 106 and 2.5 × 105 GC/g in oysters and mussels, respectively. PMA-treatment demonstrated that a large fraction of the detected norovirus corresponded to non-infectious particles. Genetic characterization showed the circulation of the GII.2[P16] and GII.4[P4] genotypes. Norovirus detection in bivalves reflects the anthropogenic impact on marine environment and serves as an early warning for the food-borne disease outbreaks resulting from the consumption of contaminated molluscs.
Show more [+] Less [-]The presence and significance of microplastics in surface water in the Lower Hudson River Estuary 2016–2019: A research note
2020
Polanco, Helen | Hayes, Siddhartha | Roble, Carrie | Krupitsky, Marika | Branco, Brett
Microplastics are a major environmental issue of concern. Since 2016, Hudson River Park has collaborated with Brooklyn College to survey microplastics within Park waters between Chambers and 59th Streets in Manhattan. It was hypothesized that microplastic concentration is influenced by proximity to combined sewer overflow (CSO) points, precipitation, and tides. Samples were collected at channel and near-shore locations at downtown and midtown sites. Microplastics were analyzed following NOAA methods via stereo microscope. Concentrations in 2018 were higher than in 2016, 2017 and 2019 ((ANOVA F (1,70) = 5.2, p < 0.03*; post hoc Tukey test p < 0.009*)), and near-shore sites tended to exhibit higher concentrations than channel sites (ANOVA and post-hoc Tukey: p < 0.03*). Microfibers were not fully accounted for and fragments were highly prevalent in all samples (~70%). Additional data will improve the understanding of the presence of microplastics in the Lower Hudson and elucidate the effects of wet weather on plastic concentrations.
Show more [+] Less [-]Comparative uptake and assimilation of nitrate, ammonium, and urea by dinoflagellate Karenia mikimotoi and diatom Skeletonema costatum s.l. in the coastal waters of the East China Sea
2020
Huang, Kaixuan | Feng, Qingliang | Zhang, Yun | Ou, Linjian | Cen, Jingyi | Lu, Songhui | Qi, Yuzao
The nitrogen uptake kinetics and physiological growth of Karenia mikimotoi and Skeletonema costatum sensu lato grown on different N substrates and concentrations were compared in the laboratory. In the presence of three N substrates, both species preferred to take up NH₄⁺. K. mikimotoi and S. costatum s.l. showed the highest substrate affinities for urea and NO₃⁻, respectively. Both species grew well on three N substrates, and the growth parameters were comparable among the different N substrates. However, K. mikimotoi assimilated urea more efficiently than it assimilated either NO₃⁻ or NH₄⁺. Different with S. costatum s.l., K. mikimotoi grew slowly and steady and the physiological and growth activities in N-depleted conditions were higher than those in N-replete conditions. Our results suggested that K. mikimotoi shows a greater readiness for uptake and assimilation of urea, and that this species is more competitive in an N-depleted environment when compared with S. costatum s.l.
Show more [+] Less [-]Perfluoroalkyl substances (PFAS) in tern eggs from St. Brandon's Atoll, Indian Ocean
2020
van der Schyff, Veronica | Kwet Yive, Nee Sun Choong | Polder, Anuschka | Cole, Nik C. | Bouwman, Hindrik
Per- and polyfluoroalkyl substances (PFAS) are anthropogenic fluorinated compounds of concern for human and environmental health. There is no data on PFAS concentrations in marine bird eggs from the Western Indian Ocean. We analysed eight PFAS in eggs of fairy terns (Gygis alba), sooty terns (Onychoprion fuscatus), and common noddies (Anous stolidus) from St. Brandon's Atoll. Fairy tern eggs contained the highest concentrations, followed by sooty terns and common noddies. Perfluoroundecanoic acid (PFUdA) had the highest mean concentration (2.3 ng/g wm), followed by perfluorooctane sulfonic acid (PFOS) (2.0 ng/g wm), and perfluorononanoic acid (PFNA) (0.93 ng/g wm) in fairy tern eggs. Concentrations of all PFAS were lower than values found in literature. PFOS and PFOA concentrations were three orders of magnitude lower than toxicity reference values and levels of lowest-observed-adverse-effect-level concentrations. Eggs from St. Brandon's would be useful to monitor background changes on a regional and perhaps global scale.
Show more [+] Less [-]Microplastics in sea-surface waters surrounding Sweden sampled by manta trawl and in-situ pump
2020
Schönlau, Christine | Karlsson, Therese M. | Rotander, Anna | Nilsson, Helena | Engwall, Magnus | van Bavel, Bert | Kärrman, Anna
Microplastics were sampled in open surface waters by using a manta trawl and an in-situ filtering pump. A total of 24 trawl samples and 11 pump samples were taken at 12 locations around Sweden. Overall, the concentration of microplastic particles was higher in pump samples compared to trawl samples. The median microplastic particle concentration was 0.04 particles per m⁻³ for manta trawl samples and 0.10 particles per m⁻³ in pump samples taken with a mesh size of 0.3 mm. The highest concentrations were recorded on the west coast of Sweden. Fibers were found in all samples and were also more frequent in the pump samples. Even higher concentrations of fibers and particles were found on the 0.05 mm pump filters. Using near-infrared hyperspectral imaging the majority of the particles were identified as polyethylene followed by polypropylene.
Show more [+] Less [-]Influences of nutritional conditions on degradation of dibutyl phthalate in coastal sediments with Cylindrotheca closterium
2020
Zhang, Fan | Chi, Jie
In this work, microphytobenthos Cylindrotheca closterium was planted on the surface of coastal sediments to investigate its influence on dibutyl phthalate (DBP) degradation in sediments under different nutritional conditions. The results indicated that C. closterium largely utilized nutrients from the overlying water. Addition of nitrogen, phosphorus or silicon increased algal biomass (as chlorophyll a) by 0.97–3.16, 1.75–2.36 and 1.61–3.09 times, respectively, meanwhile it changed bacterial community structure in sediments with C. closterium. Growth of C. closterium was more sensitive to nitrogen content in the overlying water. Inoculation of C. closterium increased the relative abundances of dominant aerobic bacteria by 10–67%. Compared with treatments without C. closterium, inoculation of C. closterium increased DBP degradation percentage in sediments (8.5–18.9% increment), which was positively correlated with chlorophyll a content. Thus, microphytobenthos showed the potential for improving the cleansing of polluted coastal sediments, which was obviously related to nutritional conditions in the overlying water.
Show more [+] Less [-]Histological, enzymatic and chemical analyses of the potential effects of differently sized microplastic particles upon long-term ingestion in zebrafish (Danio rerio)
2020
Batel, Annika | Baumann, Lisa | Carteny, Camilla Catarci | Cormier, Bettie | Keiter, Steffen H. | Braunbeck, T. (Thomas)
In microplastics (MPs) research, there is an urgent need to critically reconsider methodological approaches and results published, since public opinion and political decisions might be based on studies using debatable methods and reporting questionable results. For instance, recent studies claim that MPs induce intestinal damage and that relatively large MPs are transferred to, e.g., livers in fish. However, there is methodological criticism and considerable concern whether MP transfer to surrounding tissues is plausible. Likewise, there is an ongoing discussion in MP research if MPs act as vectors for adsorbed hazardous chemicals. In this study, effects of very small (4–6 μm) and very large (125–500 μm) benzo(a) pyrene (BaP)-spiked polyethylene (PE) particles administered via different uptake routes (food chain vs. direct uptake) were compared in a 21-day zebrafish (Danio rerio) feeding experiment. Particular care was taken to prevent cross-contamination of MPs during dissection and histological sample preparation. In contrast to numerous reports in literature describing similar approaches, independent of exposure route and MP size, no adverse effects could be detected. Likewise, no BaP accumulation could be documented, and MPs were exclusively seen in the lumen of the intestinal tract, which, however, did not induce any histopathological effects. Results indicate that in fish MPs are taken up, pass along the intestinal lumen and are excreted without any symptoms of adverse effects.
Show more [+] Less [-]Wealth blindness beyond national jurisdiction
2020
Tiller, Rachel | De Santo, Elizabeth | Mendenhall, Elizabeth | Nyman, Elizabeth | Ralby, Ian
Marine genetic resources (MGR) are a new issue in high seas management. Discussion on how to best manage these resources is currently ongoing at the United Nations, within the context of a proposed treaty on the conservation and sustainable use of marine ‘Biodiversity Beyond National Jurisdiction’ (BBNJ), which is expected to be completed in 2020.But how accurately can states measure the potential economic value of resources that still do not have a clear market application? Developing states in particular already suffer from wealth blindness, where they lack the capacity to properly evaluate the economic value or market potential of their marine resources. This article explores the extent to which wealth blindness forms the backdrop to the current debates over the potential for profitably exploiting marine genetic resources, as well as how this relates to demands for capacity building and technology transfer in the BBNJ treaty negotiation process.
Show more [+] Less [-]Natural purification capacity of tidal flats for organic matters and nutrients: A mesocosm study
2020
Kim, Taewoo | Noh, Junsung | Kwon, Bong-Oh | Lee, Changkeun | Kim, Beomgi | Kwon, Inha | Hong, Seongjin | Chang, Gap Soo | Chang, Won Keun | Nam, Jungho | Khim, Jong Seong
The regulating services by natural tidal flats to purify organic pollutants are increasingly recognized, but a quantitative assessment is very limited. We developed a mesocosm system to determine removal efficiency of organic matters and nutrients by simulating a natural tidal condition. The tidal flat sediments significantly removed waterborne organic pollutants to background levels in ~2 and 6–7 days for COD and TP, respectively. This rapid removal of organic matters by natural sediments could be attributed to the microbe community degrading the corresponding pollutants. Temporal trend and degree of removal rates for COD and TP were similar between the bare tidal flat and the salt marsh. Meantime, the salt marsh environment removed waterborne DIP much quickly and also efficiently, implying a high affinity of halophytes on dissolved organic matters. Of note, sedimentary organic sink prevailed in defaunated condition under the smaller bioturbation effect. A mini-review on the purification capacity of natural and/or constructed coastal wetlands generally supported a high efficiency of vegetation to remove various sources of organic matters.
Show more [+] Less [-]Characterization of sediment contaminants in Arctic lagoons and estuaries
2020
Hartwell, S Ian | Lomax, Terri | Dasher, Doug
Baseline characterizations of estuarine sediments in Chukchi and Beaufort Seas, were conducted. Concentrations of 194 organic and elemental chemicals were analyzed in sediment and fish, plus stable isotopes of carbon and nitrogen. The estuaries are shallow embayments, with little shoreline relief. The water columns were turbid, high salinity, and not stratified. Concentrations of arsenic and nickel were elevated throughout the region. Arsenic in fish tissue was elevated. Concentrations of PAHs were relatively high for pristine locations, but did not include petroleum hydrocarbons. Characteristics of PAHs indicate large contributions of terrestrial organic matter. With the exception of Peard Bay, all the estuaries reflected the strong influence of terrestrial plant input with low δₒ/ₒₒ values for carbon and nitrogen. Chlorinated pesticides and PCBs were uniformly low, but detectable in fish tissue. PCB and cyclodiene concentrations were half that seen in southeast Bristol Bay. Hexachlorobenzene was detected in all fish samples.
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