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Travelling light: Fouling biota on macroplastics arriving on beaches of remote Rapa Nui (Easter Island) in the South Pacific Subtropical Gyre Full text
2018
Rech, Sabine | Thiel, Martin | Borrell Pichs, Yaisel J. | García Vázquez, Eva
Marine anthropogenic debris was sampled from two beaches on the remote South Pacific island Rapa Nui (Easter Island). Abundance, composition, and the attached fouling assemblages on stranded litter were analysed. Most litter (n = 172 items found) was composed of plastic material, and 34% of all litter items were fouled. The main fouling species was the encrusting bryozoan Jellyella eburnea. Transporting vectors were exclusively made from plastics and were mainly small items and fragments, probably stemming from the South Pacific Subtropical Gyre. We present the first report of Planes major, Halobates sericeus, and Pocillopora sp. on anthropogenic litter in the South Pacific.
Show more [+] Less [-]Pyr-GC/MS analysis of microplastics extracted from the stomach content of benthivore fish from the Texas Gulf Coast Full text
2018
Peters, Colleen A. | Hendrickson, Erik | Minor, Elizabeth C. | Schreiner, Kathryn | Halbur, Julie | Bratton, Susan P.
Fish ingestion of microplastic has been widely documented throughout freshwater, marine, and estuarine species. While numerous studies have quantified and characterized microplastic particles, analytical methods for polymer identification are limited. This study investigated the applicability of pyr-GC/MS for polymer identification of microplastics extracted from the stomach content of marine fish from the Texas Gulf Coast. A total of 43 microplastic particles were analyzed, inclusive of 30 fibers, 3 fragments, and 10 spheres. Polyvinyl chloride (PVC) and polyethylene terephthalate (PET) were the most commonly identified polymers (44.1%), followed by nylon (9.3%), silicone (2.3%), and epoxy resin (2.3%). Approximately 42% of samples could not be classified into a specific polymer class, due to a limited formation of pyrolytic products, low product abundance, or a lack of comparative standards. Diethyl phthalate, a known plasticizer, was found in 16.3% of the total sample, including PVC (14.3%), silicone (14.3%), nylon (14.3%), and sample unknowns (57.2%).
Show more [+] Less [-]Detection and quantification of human adenovirus (HAdV), JC polyomavirus (JCPyV) and hepatitis A virus (HAV) in recreational waters of Niterói, Rio de Janeiro, Brazil Full text
2018
Dias, Juliana | Pinto, Renan Novaes | Vieira, Carmen Baur | de Abreu Corrêa, Adriana
This study evaluated the impact of sewage discharge in recreational coastal marine environments of Niteroi, Rio de Janeiro, Brazil, over a six-month period by the detection of waterborne enteric viruses. Ten-liter water samples were collected in four beaches from January to July 2017. Viruses were concentrated by an organic flocculation and human adenoviruses (HAdV), polyomavirus (JCPyV), and Hepatitis A virus (HAV) detected by qPCR. Forty-eight water samples were collected, being 43% positive for HAdV and 23% for JCPyV; only one sample was positive for HAV. Viruses were detected in all sampling sites, including in areas suitable for bathing according to the current bacterial standards. The results herein provide an overview of the viral contamination of beaches used for recreational purposes. The viral presence in the sampled areas indicates the need for more rigid effluent discharge controls in these areas, as sewage represents a possible transmission risk for waterborne viral diseases.
Show more [+] Less [-]Use of a monoclonal antibody-based assay for the early detection of an invasive bivalve in plankton samples Full text
2018
Montes, Agar | Lorenzo-Abalde, Silvia | González Fernández, África | Vázquez, Elsa | Olabarria, Celia
The invasive mussel Xenostrobus securis was recorded for the first time in the Galician Rias Baixas (NW Spain) in 2007, within an area characterized by intense commercial culture of Mytilus galloprovincialis. The main aims of this study were to evaluate whether an immunological assay can be used to detect larvae of this species in field samples of plankton and to determine whether the distribution of larvae matched that of adults. The ability of two monoclonal antibodies to recognize the bivalve was tested by immunofluorescence. Only the M22.8 antibody recognized X. securis larvae. The staining pattern distinguished X. securis from M. galloprovincialis larvae in both laboratory cultures and field samples of plankton. The distribution of larvae did not match that of adults. This tool may prove very useful for monitoring the presence of this invasive species in the plankton, allowing rapid and specific recognition.
Show more [+] Less [-]Cu, Pb and Fe release from sulfide-containing tailings in seawater: Results from laboratory simulation of submarine tailings disposal Full text
2018
Embile, Rodrigo F. | Walder, Ingar F. | Schuh, Christopher | Donatelli, Jenna Lee
Metal release from the deposition of sulfide-containing tailings in seawater was investigated using a batch reaction experiment inside a temperature and dissolved oxygen-controlled chamber. Two hundred grams of tailings from a porphyry Cu-Au and a sediment-hosted Cu deposit were submerged in 1.8 L synthetic seawater. The sulfides present in the porphyry Cu-Au tailings are pyrite (FeS2), chalcopyrite (CuFeS2) and bornite (Cu5FeS4) while in the sediment-hosted Cu tailings are bornite, chalcocite (Cu2S) and covellite (CuS). Galena occurs as a minor sulfide in both tailings. Pore water and overlying seawater samples were collected and analyzed for pH, redox potential and trace metals (Cu, Pb and Fe) concentration. Results show that there is very low Cu (10–40 μg/L), Pb (1–10 μg/L) and Fe (5–50 μg/L) released into solution throughout the course of 87 days. Long-term trace metal release from tailings in seawater is therefore theorized to be low and is a slow process.
Show more [+] Less [-]First evidence of ingested plastics by a high commercial shrimp species (Plesionika narval) in the eastern Mediterranean Full text
2018
Bordbar, L. | Kapiris, K. | Kalogirou, S. | Anastasopoulou, A.
This study provides the first evidence of nylon filament occurrence in the stomach of an economically important target shrimp species in the Mediterranean Sea, Plesionika narval (Fabricius, 1787). Samples were collected monthly from November 2014 to October 2015 from shallow (10–30 m) and deeper waters (150–170 m). The occurrence of plastics in the stomachs of the Narwal shrimp was 5.93% and identified as Nylon by FT-IR analysis. Higher percentages of ingested plastics were found in females from shallower depths and in males from deeper waters. The maximum number of plastics was recorded in January and March, possibly related to the higher feeding intensity of females prior to their reproduction period. A total of 10.3% of females and 4.8% of males with ingested plastics had almost empty stomachs. The presence of plastics in the stomach of P. narval is an evidence of passive ingestion which in this study related to fishing activities.
Show more [+] Less [-]Six decades of change in pollution and benthic invertebrate biodiversity in a southern New England estuary Full text
2018
Hale, Stephen S. | Buffum, Henry W. | Hughes, Melissa M.
Pollution has led to a decline of benthic invertebrate biodiversity of Narragansett Bay, raising questions about effects on ecosystem functions and services including shellfish production, energy flow to fishes, and biogeochemical cycles. Changes in community composition and taxonomic distinctness (biodiversity) were calculated from the 1950s—when quantitative benthic invertebrate data first became available—to 2015. Change in community composition of the bay was correlated with changes in dissolved inorganic nitrogen, dissolved oxygen, and sediment contaminants. A mid-bay reference site showed moderate changes in community composition but no change in biodiversity. In contrast, a more impacted site in the upper bay showed substantial differences in community composition over time and a decline in taxonomic distinctness. Bay-wide, as inputs of some stressors such as nutrients and sediment contaminants have declined, there are signs of recovery of benthic biodiversity but other stressors such as temperature and watershed development are increasing.
Show more [+] Less [-]Quantity and types of microplastics in the organic tissues of the eastern oyster Crassostrea virginica and Atlantic mud crab Panopeus herbstii from a Florida estuary Full text
2018
Waite, Heidi R. | Donnelly, Melinda J. | Walters, Linda J.
This study determined the quantity and diversity of microplastics in water and soft tissues of eastern oysters (Crassostrea virginica) and Atlantic mud crabs (Panopeus herbstii) in Mosquito Lagoon, a shallow, microtidal estuary along the east coast of central Florida. One-liter water samples had an average of 23.1 microplastic pieces (n = 15). Crabs (n = 90) had an average of 4.2 pieces in tissues/individual plus an average of 20.3 pieces/individual temporarily entangled in exposed surfaces and released within 5 days in tanks. Adult oysters (n = 90) had an average of 16.5 microplastic pieces/individual. Fibers, mostly royal/dark blue in color, dominated our collections. When compared per gram of tissue, crabs had two orders of magnitude more microplastic pieces than oysters. Our numbers were higher than previous studies on invertebrate microplastics; this is potentially the result of extensive urbanization, limited flushing, and intensive recreational usage of Mosquito Lagoon.
Show more [+] Less [-]Estimating the acute impacts of Arctic marine oil spills using expert elicitation Full text
2018
Nevalainen, Maisa | Helle, Inari | Vanhatalo, Jarno
Increasing maritime traffic in the Arctic has heightened the oil spill-related risks in this highly sensitive environment. To quantitatively assess these risks, we need knowledge about both the vulnerability and sensitivity of the key Arctic functional groups that may be affected by spilled oil. However, in the Arctic these data are typically scarce or lacking altogether. To compensate for this limited data availability, we propose the use of a probabilistic expert elicitation methodology, which we apply to seals, anatids, and seabirds. Our results suggest that the impacts of oil vary between functional groups, seasons, and oil types. Overall, the impacts are least for seals and greatest for anatids. Offspring seem to be more sensitive than adults, the impact is greatest in spring, and medium and heavy oils are the most harmful oil types. The elicitation process worked well, yet finding enough skilled and motivated experts proved to be difficult.
Show more [+] Less [-]Impact of coastal power plant cooling system on planktonic diversity of a polluted creek system Full text
2018
Prince Prakash Jebakumar, Jebarathnam | Nandhagopal, Ganesan | Rajan Babu, Bose | Ragumaran, Shunmugavel | Ravichandran, Vijaya
A tropical coastal power plant with a once-through cooling system that pumped sea water along with tiny marine phytoplankton and zooplankton for waste heat discharge recorded reduction in the population density of these organisms by 64% and 93%, respectively, at the discharge site. The depletion of organic carbon is 0.69 tons per annum with loss of 20 to 24 lakhs fish fecundity. The synergistic effect of tropical summer ambiance and waste heat discharge from the power plant considerably reduced the phytoplankton population in the coolant water discharge point during April, June, and July. This resulted in changes in the phytoplankton community structure from Bacillariophyceae > Dyanophyceae > Cyanophyceae to Bacillariophyceae > Cyanophyceae > Dyanophyceae in the Ennore creek system. A unique epibiotic assemblage of the diatoms Licmophora juergensii and Licmophora flabellata was observed on Phormidium sp., a mat-forming Cyanobacterium preharbored along the 4.5-km-long transport channel of the cooling tower blow out of the thermal power plant. These pedunculate fouling diatoms have a symbiotic association with Phormidium sp., which grows few microns high above the substrate, thus creating obstructive flow in cooling water channels of the power plant. Further, loss of fish larvae during zooplankton population reduction creates an impact on the local fishery. However, the emerging scenario of global warming predicts that the migration of fish population toward cooler regions shall further aggravate the fishery reduction near the power plant cooling operation along the tropical coasts. The marine organisms living in tropical coastal waters operated at upper limits of thermal tolerance produce a demand for the regulatory bodies in India to enforce a drop in discharge criteria for coolant water, with the pre-existing power stations permitted to discharge up to 10 °C above the ambient temperature and newer power stations permitted to discharge a maximum of 7 °C. It becomes a requisite for power stations to draw additional seawater along with the plankton. Therefore, an emerging technology of subsurface intake systems called beachwell that resolves the issue of coolant water intake without biota was advocated.
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