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Beach-cast debris surveys on Triangle Island, British Columbia, Canada indicate the timing of arrival of 2011 Tōhoku tsunami debris in North America Full text
2018
Hipfner, J Mark | Lok, Erika K. | Jardine, Catherine | Studholme, Katharine R. | (Belette) Lebeau, Agathe C. | Wright, Kenneth G. | Trefry, Sarah A. | Drever, Mark C. | Jones, Gregory
We conducted beach-cast debris transect surveys on Triangle Island, British Columbia, Canada in 2012–2017 to (1) establish a baseline against which to track future changes in stranded debris on this small, uninhabited island; and (2) time the arrival in western North America of debris released by the 2011 Tōhoku tsunami. Most (90%) of the six-year total of 6784 debris items tallied was composed of Styrofoam or plastic. The number of debris items peaked in 2014 (waste Styrofoam, rope) and 2015 (waste plastic, wood), and cumulative totals for all debris types were ca. 50% higher in 2014–15 than in 2012–13 and 2016–17. The peaks in 2014–15 probably represented the arrival of the bulk of the tsunami debris, based on close correspondence with forecasting models and debris surveys elsewhere. A fuller understanding of the movement of the Tōhoku tsunami debris will require information from other beach monitoring programs.
Show more [+] Less [-]A baseline study on the concentration of trace elements in the surface sediments off Southwest coast of Tamil Nadu, India Full text
2018
Godson, Prince S. | Magesh, N.S. | Peter, T Simon | Chandrasekar, N. | Krishnakumar, S. | Vincent, Salom Gnana Thanga
Forty two surface sediment samples were collected in order to document baseline elemental concentration along the Southwest coast of Tamil Nadu, India. The elements detected were Manganese (Mn), Zinc (Zn), Iron (Fe), Copper (Cu), Nickel (Ni) and Lead (Pb). The concentration of Fe and Mn was primarily controlled by the riverine input. The source of Pb and Zn is attributed to leaded petrol and anti-biofouling paints. The calculated index (EF, Igeo and CF) suggests that the sediments of the study area are significantly enriched with all elements except Pb. The contamination factor showed the order of Mn>Zn>Fe>Cu>Ni>Pb. The sediment pollution index (SPI) revealed that the sediments belonged to low polluted to dangerous category. The correlation matrix and dendrogram showed that the elemental distribution was chiefly controlled by riverine input as well as anthropogenic activity in the coast.
Show more [+] Less [-]Biodegradation of dispersed oil in seawater is not inhibited by a commercial oil spill dispersant Full text
2018
Brakstad, Odd G. | Ribicic, Deni | Winkler, Anika | Netzer, Roman
Chemical dispersants are well-established as oil spill response tools. Several studies have emphasized their positive effects on oil biodegradation, but recent studies have claimed that dispersants may actually inhibit the oil biodegradation process. In this study, biodegradation of oil dispersions in natural seawater at low temperature (5°C) was compared, using oil without dispersant, and oil premixed with different concentrations of Slickgone NS, a widely used oil spill dispersant in Europe. Saturates (nC10-nC36 alkanes), naphthalenes and 2- to 5-ring polycyclic aromatic hydrocarbons (PAH) were biotransformed at comparable rates in all dispersions, both with and without dispersant. Microbial communities differed primarily between samples with or without oil, and they were not significantly affected by increasing dispersant concentrations. Our data therefore showed that a common oil spill dispersant did not inhibit biodegradation of oil at dispersant concentrations relevant for response operations.
Show more [+] Less [-]Levels of trace metals on microplastic particles in beach sediments of the island of Vis, Adriatic Sea, Croatia Full text
2018
Maršić-Lučić, Jasna | Lušić, Jelena | Tutman, Pero | Bojanić Varezić, Dubravka | Šiljić, Jasna | Pribudić, Joško
The aim of this study was to determine the levels of trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in plastic pellets collected from two sandy beaches on the island of Vis, Croatia. A total of 92 pellets in a sediment volume of 3965 mL were collected at the investigated sampling sites. Concentrations of pellets in sediment samples ranged from 6 to 36 particles dm−3 of wet sediment. Mean particle weight of the collected beached pellets ranged from 17 mg to 31 mg. Trace metal concentrations in plastic pellets were greater than the concentrations reported for seawater in the investigated area, which indicates that plastic pellets sorb metals from the marine environment. The adsorbed trace metals may enter the food chain due to incidental ingestion of microplastic particles by marine animals, which presents a potential human health risk due to consumption of seafood.
Show more [+] Less [-]Potential microbial consortium involved in the biodegradation of diesel, hexadecane and phenanthrene in mangrove sediment explored by metagenomics analysis Full text
2018
Tiralerdpanich, Parichaya | Sonthiphand, Prinpida | Luepromchai, Ekawan | Pinyakong, Onruthai | Pokethitiyook, Prayad
Hydrocarbon contamination is a serious problem that degrades the quality of mangrove ecosystems, and bioremediation using autochthonous bacteria is a promising technology to recover an impacted environment. This research investigates the biodegradation rates of diesel, hexadecane and phenanthrene, by conducting a microcosm study and survey of the autochthonous microbial community in contaminated mangrove sediment, using an Illumina MiSeq platform. The biodegradation rates of diesel, hexadecane and phenanthrene were 82, 86 and 8 mg kg⁻¹ sediment day⁻¹, respectively. The removal efficiencies of hexadecane and phenanthrene were >99%, whereas the removal efficiency of diesel was 88%. A 16S rRNA gene amplicon sequence analysis revealed that the major bacterial assemblages detected were Gammaproteobacteria, Deltaproteobacteria, Alphaproteobacteria. The bacterial compositions were relatively constant, while reductions of the supplemented hydrocarbons were observed. The results imply that the autochthonous microorganisms in the mangrove sediment were responsible for the degradation of the respective hydrocarbons. Diesel-, hexadecane- and phenanthrene-degrading bacteria, namely Bacillus sp., Pseudomonas sp., Acinetobacter sp. and Staphylococcus sp., were also isolated from the mangrove sediment. The mangrove sediment provides a potential resource of effective hydrocarbon-degrading bacteria that can be used as an inoculum or further developed as a ready-to-use microbial consortium for the purpose of bioremediation.
Show more [+] Less [-]Securing a port's future through Circular Economy: Experiences from the Port of Gävle in contributing to sustainability Full text
2018
Carpenter, Angela | Lozano, Rodrigo | Sammalisto, Kaisu | Astner, Linda
Ports are an important player in the world, due to their role in global production and distributions systems. They are major intermodal transport hubs, linking the sea to the land. For all ports, a key requirement for commercial and economic viability is to retain ships using them and to remain accessible to those ships. Ports need to find approaches to help them remain open. They must ensure their continued economic viability. At the same time, they face increasing pressure to become more environmentally and socially conscious. This paper examines the approach taken by the Port of Gävle, Sweden, which used contaminated dredged materials to create new land using principles of Circular Economy. The paper demonstrates that using Circular Economy principles can be a viable way of securing a port's future and contributing to its sustainability, and that of the city/region where it operates.
Show more [+] Less [-]Integrated disperser freezing purification with extraction using fatty acid-based solidification of floating organic-droplet (IDFP-EFA-SFO) for triclosan and methyltriclosan determination in seawater, sediment and seafood Full text
2018
Gao, Ming | Wang, Jun | Zhang, Xiaona | Dahlgren, Randy A. | Ru, Shaoguo | Wang, Xuedong
A microextraction method for the determination of triclosan and methyltriclosan in marine environmental samples was developed. The disperser was first serves as a preliminary extractant for analytes, then as a frozen solvent to remove impurities at −20 °C, and finally as a disperser agent in the microextraction procedure. With the extractants solidified and float on the surface of the aqueous phase at low temperature, a separation was achieved to avoided use of specialized laboratory instruments. The method was optimized using Plackett-Burman design and central composite design as follows: 146 μL octanoic acid as extractant, 793 μL acetoneas disperser, 3.0 min centrifugation and 1.1 min vortex time. The limits of detection were 0.022–0.060 μg L−1 or μg kg−1 and recoveries were 83.3–103.5% for TCS and MTCS in seawater, sediments and seafood. The method has excellent prospects for sample pre-treatment and trace-level analysis of triclosan and methyltriclosan in marine environmental samples.
Show more [+] Less [-]First evidence of microplastic ingestion by fishes from the Amazon River estuary Full text
2018
Pegado, Tamyris de Souza e Silva | Schmid, Kurt | Winemiller, Kirk O. | Chelazzi, David | Cincinelli, Alessandra | Dei, Luigi | Giarrizzo, Tommaso
This study investigated occurrence of microplastic particles in digestive tracts of fishes from the Amazon River estuary. A total of 189 fish specimens representing 46 species from 22 families was sampled from bycatch of the shrimp fishery. Microplastic particles removed from fish gastrointestinal tracts were identified using Attenuated Total Reflectance – Fourier Transform Infrared (ATR-FTIR). In total, 228 microplastic particles were removed from gastrointestinal tracts of 26 specimens representing 14 species (30% of those examined). Microplastic particles were categorized as pellets (97.4%), sheets (1.3%), fragments (0.4%) and threads (0.9%), with size ranging from 0.38 to 4.16 mm. There was a positive correlation between fish standard length and number of particles found in gastrointestinal tracts. The main polymers identified by ATR-FTIR were polyamide, rayon and polyethylene. These findings provide the first evidence of microplastic contamination of biota from the Amazon estuary and northern coast of Brazil.
Show more [+] Less [-]Fate of hopane biomarkers during in-situ burning of crude oil — A laboratory-scale study Full text
2018
John, Gerald F. | Han, Yuling. | Clement, T Prabhakar
In-situ burning (ISB) is a remediation strategy that is used for managing oil spills. ISB generates heavy residues that can submerge and negatively impact benthic environments. To track the fate of toxic contaminants in ISB residues, a conservative hopane biomarker, such as C₃₀-αβ hopane, is often used. Furthermore, diagnostic ratios of various hopanes are used for source oil identification. Use of these biomarkers assume that during ISB the quantity of C₃₀-αβ hopane will be conserved, and the diagnostic ratios of various hopanes will be stable. The objective of this study is to test the validity of these two assumptions. We conducted laboratory-scale ISB experiments using a model oil prepared from commercial C₃₀-αβ hopane standard, and a reference crude oil. Laboratory data collected under controlled burning conditions show that C₃₀-αβ hopane will not be conserved; however, the diagnostic ratios of hopanes will still remain fairly stable.
Show more [+] Less [-]Multiple field-based methods to assess the potential impacts of seismic surveys on scallops Full text
2018
Przeslawski, Rachel | Huang, Zhi | Anderson, Jade | Carroll, Andrew G. | Edmunds, Matthew | Hurt, Lynton | Williams, Stefan
Marine seismic surveys are an important tool to map geology beneath the seafloor and manage petroleum resources, but they are also a source of underwater noise pollution. A mass mortality of scallops in the Bass Strait, Australia occurred a few months after a marine seismic survey in 2010, and fishing groups were concerned about the potential relationship between the two events. The current study used three field-based methods to investigate the potential impact of marine seismic surveys on scallops in the region: 1) dredging and 2) deployment of Autonomous Underwater Vehicles (AUVs) were undertaken to examine the potential response of two species of scallops (Pecten fumatus, Mimachlamys asperrima) before, two months after, and ten months after a 2015 marine seismic survey; and 3) MODIS satellite data revealed patterns of sea surface temperatures from 2006–2016. Results from the dredging and AUV components show no evidence of scallop mortality attributable to the seismic survey, although sub-lethal effects cannot be excluded. The remote sensing revealed a pronounced thermal spike in the eastern Bass Strait between February and May 2010, overlapping the scallop beds that suffered extensive mortality and coinciding almost exactly with dates of operation for the 2010 seismic survey. The acquisition of in situ data coupled with consideration of commercial seismic arrays meant that results were ecologically realistic, while the paired field-based components (dredging, AUV imagery) provided a failsafe against challenges associated with working wholly in the field. This study expands our knowledge of the potential environmental impacts of marine seismic survey and will inform future applications for marine seismic surveys, as well as the assessment of such applications by regulatory authorities.
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