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Citizen scientists reveal: Marine litter pollutes Arctic beaches and affects wild life Full text
2017
Bergmann, Melanie | Lutz, Birgit | Tekman, Mine B. | Gutow, Lars
Citizen scientists reveal: Marine litter pollutes Arctic beaches and affects wild life Full text
2017
Bergmann, Melanie | Lutz, Birgit | Tekman, Mine B. | Gutow, Lars
Recent data indicate accumulation areas of marine litter in Arctic waters and significant increases over time. Beaches on remote Arctic islands may be sinks for marine litter and reflect pollution levels of the surrounding waters particularly well. We provide the first quantitative data from surveys carried out by citizen scientists on six beaches of Svalbard. Litter quantities recorded by cruise tourists varied from 9–524gm−2 and were similar to those from densely populated areas. Plastics accounted for >80% of the overall litter, most of which originated from fisheries. Photographs provided by citizens show deleterious effects of beach litter on Arctic wildlife, which is already under strong pressure from global climate change. Our study highlights the potential of citizen scientists to provide scientifically valuable data on the pollution of sensitive remote ecosystems. The results stress once more that current legislative frameworks are insufficient to tackle the pollution of Arctic ecosystems.
Show more [+] Less [-]Citizen scientists reveal: marine litter pollutes Arctic beaches and affects wild life Full text
2017
Bergmann, Melanie | Lutz, Birgit | Tekman, Mine Banu | Gutow, Lars
Recent data indicate accumulation areas of marine litter in Arctic waters and significant increases over time. Beaches on remote Arctic islands may be sinks for marine litter and reflect pollution levels of the surrounding waters particularly well. We provide the first quantitative data from surveys carried out by citizen scientists on six beaches of Svalbard. Litter quantities recorded by cruise tourists varied from 9-524 g m-2 and were similar to those from densely populated areas. Plastics accounted for >80% of the overall litter, most of which originated from fisheries. Photographs provided by citizens show deleterious effects of beach litter on Arctic wildlife, which is already under strong pressure from global climate change. Our study highlights the potential of citizen scientists to provide scientifically valuable data on the pollution of sensitive remote ecosystems. The results stress once more that current legislative frameworks are insufficient to tackle the pollution of Arctic ecosystems.
Show more [+] Less [-]Marine Litter quantities on six Beaches of northern Svalbard in 2016 determined by citizen scientists Full text
2017
Bergmann, Melanie | Gutow, Lars
Beaches on remote Arctic islands may be sinks for marine litter and reflect pollution levels of the surrounding waters particularly well. We provide the first quantitative data from surveys carried out by citizen scientists on six beaches of northern Svalbard. Litter quantities recorded by cruise tourists varied from 9-524 g m-2 and were similar to those from densely populated areas. Plastics accounted for >80% of the overall litter, most of which originated from fisheries. Our study highlights the potential of citizen scientists to provide scientifically valuable data on the pollution of sensitive remote ecosystems. The results stress once more that current legislative frameworks are insufficient to tackle the pollution of Arctic ecosystems.
Show more [+] Less [-]Phytochelatins and monothiols in salt marsh plants and their relation with metal tolerance Full text
2017
Negrin, Vanesa L. | Teixeira, Bárbara | Godinho, Rita M. | Mendes, Rogério | Vale, Carlos
Phytochelatins and monothiols in salt marsh plants and their relation with metal tolerance Full text
2017
Negrin, Vanesa L. | Teixeira, Bárbara | Godinho, Rita M. | Mendes, Rogério | Vale, Carlos
Phytochelatins (PCs) and monothiols and their relation with trace element concentrations were studied in three plant species from two Portuguese salt marshes. Belowground tissues showed always higher element concentrations, while enhanced values of monothiols were found in aboveground biomass. Glutathione was usually the most abundant monothiol. The concentration of total PCs was higher in leaves or stems than in roots of Halimione portulacoides and Sarcocornia perennis, while in Spartina maritima the highest concentrations were reported in large roots. PC2 was synthesized by all tissues and species and was higher in large roots of S. maritima. PC4 and PC5 were in high levels in small roots of S. maritima. PC2 was positively correlated with As, Zn and Pb. Although being the first evidence of PCs and monothiols in these species under natural conditions, our results do not point to a simple relationship with elements concentrations, suggesting a complex mechanism involved.
Show more [+] Less [-]Phytochelatins and monothiols in salt marsh plants and their relation with metal tolerance Full text
2017
Negrin, Vanesa Lorena | Teixeira, Bárbara | Godinho, Rita M. | Mendes, Rogério | Vale, Carlos
Phytochelatins (PCs) and monothiols and their relation with trace element concentrations were studied in three plant species from two Portuguese salt marshes. Belowground tissues showed always higher element concentrations, while enhanced values of monothiols were found in aboveground biomass. Glutathione was usually the most abundant monothiol. The concentration of total PCs was higher in leaves or stems than in roots of Halimione portulacoides and Sarcocornia perennis, while in Spartina maritima the highest concentrations were reported in large roots. PC2 was synthesized by all tissues and species and was higher in large roots of S. maritima. PC4 and PC5 were in high levels in small roots of S. maritima. PC2 was positively correlated with As, Zn and Pb. Although being the first evidence of PCs and monothiols in these species under natural conditions, our results do not point to a simple relationship with elements concentrations, suggesting a complex mechanism involved. | Fil: Negrin, Vanesa Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Instituto Português do Mar e da Atmosfera; Portugal | Fil: Teixeira, Bárbara. Instituto Português do Mar e da Atmosfera; Portugal | Fil: Godinho, Rita M.. Instituto Português do Mar e da Atmosfera; Portugal | Fil: Mendes, Rogério. Instituto Português do Mar e da Atmosfera; Portugal | Fil: Vale, Carlos. Instituto Português do Mar e da Atmosfera; Portugal. Universidad de Porto; Portugal
Show more [+] Less [-]Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea Full text
2017
Roca, Guillem | Romero, Javier | Farina, Simone | Martínez-Crego, Begoña | Alcoverro, Teresa
Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea Full text
2017
Roca, Guillem | Romero, Javier | Farina, Simone | Martínez-Crego, Begoña | Alcoverro, Teresa
To manage trace metal pollution it is critical to determine how much temporal trends can be attributed to local or large-scale sources. We tracked changes in metal content in the seagrass Posidonia oceanica, along the NW Mediterranean from 2003 to 2010. While Cu, Cd and Ni showed a large inter-site variation, likely due to local factors, Fe, Mn and Pb showed little local variation and synchronous interannual variability across sites, most likely due to large-scale sources. Zn showed equal importance of local and large-scale sources of variation. Temporal trends of Ni, Zn, Cd, Cu remained almost stable. In contrast, Fe, Mn and Pb slightly increased in the last decade. These trends suggest that metals like Cu, Cd, Ni can be effectively managed at local scale. Whereas, elements like Fe, Mn and Pb have an important large-scale component that needs to be managed across the frontiers of national jurisdictions.
Show more [+] Less [-]Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea Full text
2017
Roca, Guillem | Romero, Javier | Farina, Simone | Martínez-Crego, Begoña | Alcoverro, Teresa
To manage trace metal pollution it is critical to determine how much temporal trends can be attributed to local or large-scale sources. We tracked changes in metal content in the seagrass Posidonia oceanica, along the NW Mediterranean from 2003 to 2010. While Cu, Cd and Ni showed a large inter-site variation, likely due to local factors, Fe, Mn and Pb showed little local variation and synchronous interannual variability across sites, most likely due to large-scale sources. Zn showed equal importance of local and large-scale sources of variation. Temporal trends of Ni, Zn, Cd, Cu remained almost stable. In contrast, Fe, Mn and Pb slightly increased in the last decade. These trends suggest that metals like Cu, Cd, Ni can be effectively managed at local scale. Whereas, elements like Fe, Mn and Pb have an important large-scale component that needs to be managed across the frontiers of national jurisdictions. | Agenda Catalana de l'Aigua [CV04000002] | Spanish Ministry of Science and Innovation [CTM2013-48027-C3.3-R, CTM2013-48027-C3-1-R] | Agenda de Gestic d'Ajuts Universitaris i de Recerca of Generalitat de Catalunya
Show more [+] Less [-]Combined effects of temperature and copper and S-metolachlor on embryo-larval development of the Pacific oyster, Crassostrea gigas Full text
2017
Gamain, Perrine | Gonzalez, Patrice | Cachot, Jérôme | Clérandeau, Christelle | Mazzella, Nicolas | Gourves, Pierre Yves | Morin, Bénédicte
Combined effects of temperature and copper and S-metolachlor on embryo-larval development of the Pacific oyster, Crassostrea gigas Full text
2017
Gamain, Perrine | Gonzalez, Patrice | Cachot, Jérôme | Clérandeau, Christelle | Mazzella, Nicolas | Gourves, Pierre Yves | Morin, Bénédicte
This study evaluates the combined effects of two contaminants (copper and a herbicide S-metolachlor) and temperature on the early life stages of the Pacific oyster Crasssotrea gigas, which is native to Arcachon Bay (southwest France). The responses of D-larvae, obtained from wild and cultivated oysters, were investigated for one year during the oyster breeding period at different sampling sites and compared with the response of D-larvae from a commercial hatchery. Embryotoxicity was measured by considering the percentage of abnormal D-shaped larvae. Normal development of embryos occurred only from 22°C to 26°C. There were synergistic effects of copper at low and high temperatures. Native oysters appear particularly sensitive to an increase in water temperature, suggesting a future increase in the percentage of larval abnormalities as a result of global climate change. Hatchery oysters represent a good alternative model for studying the effects of both pollutants and climate change stressors.
Show more [+] Less [-]Combined effects of temperature and copper and S-metolachlor on embryo-larval development of the Pacific oyster, Crassostrea gigas Full text
2017
Gamain, Perrine | Gonzalez, Patrice | Cachot, Jérôme | Clérandeau, Christelle | Mazzella, Nicolas | Gourves, Pierre Yves | Morin, Bénédicte | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | This study evaluates the combined effects of two contaminants (copper and a herbicide S-metolachlor) and temperature on the early life stages of the Pacific oyster Crasssotrea gigas,which is native to Arcachon Bay (southwest France). The responses of D-larvae, obtained fromwild and cultivated oysters,were investigated for one year during the oyster breeding period at different sampling sites and compared with the response of D-larvae from a commercial hatchery. Embryotoxicity was measured by considering the percentage of abnormal D-shaped larvae. Normal development of embryos occurred only from 22 °C to 26 °C. There were synergistic effects of copper at low and high temperatures. Native oysters appear particularly sensitive to an increase in water temperature, suggesting a future increase in the percentage of larval abnormalities as a result of global climate change. Hatchery oysters represent a good alternative model for studying the effects of both pollutants and climate change stressors.
Show more [+] Less [-]Concentrations of mercury and other trace elements in two offshore skates: sandy ray Leucoraja circularis and shagreen ray L. fullonica Full text
2017
Nicolaus, E.E Manuel | Barry, Jon | Bolam, Thi P.C. | Lorance, Pascal | Marandel, Florianne | McCully Phillips, Sophy R. | Neville, Suzanna | Ellis, Jim
Concentrations of mercury and other trace elements in two offshore skates: sandy ray Leucoraja circularis and shagreen ray L. fullonica Full text
2017
Nicolaus, E.E Manuel | Barry, Jon | Bolam, Thi P.C. | Lorance, Pascal | Marandel, Florianne | McCully Phillips, Sophy R. | Neville, Suzanna | Ellis, Jim
Trace metal concentrations in muscle and liver tissues from two offshore species of skate were examined. Concentrations of mercury in muscle of Leucoraja circularis (n=20; 23–110.5cm total length, 157–490m water depth) and L. fullonica (n=24; 28.5–100cm total length, 130–426m water depth) were 0.02–1.8 and 0.04–0.61mgkg−1, respectively. Concentrations of both As and Hg increased with total length. Only the largest specimen had a concentration of Hg in muscle >1.0mgkg−1. Data were limited for specimens>90cm long, and further studies on contaminants in larger-bodied skates could usefully be undertaken.
Show more [+] Less [-]Concentrations of mercury and other trace elements in two offshore skates: sandy ray Leucoraja circularis and shagreen ray L. fullonica Full text
2017
Nicolaus, E. E. Manuel | Barry, Jon | Bolam, Thi P. C. | Lorance, Pascal | Marandel, Florianne | Phillips, Sophy R. Mccully | Neville, Suzanna | Ellis, Jim R.
Trace metal concentrations in muscle and liver tissues from two offshore species of skate were examined. Concentrations of mercury in muscle of Leucoraja circularis (n = 20; 23–110.5 cm total length, 157–490 m water depth) and L. fullonica (n = 24; 28.5–100 cm total length, 130–426 m water depth) were 0.02–1.8 and 0.04–0.61 mg kg− 1, respectively. Concentrations of both As and Hg increased with total length. Only the largest specimen had a concentration of Hg in muscle > 1.0 mg kg− 1. Data were limited for specimens > 90 cm long, and further studies on contaminants in larger-bodied skates could usefully be undertaken.
Show more [+] Less [-]Bioaugmentation with bacteria selected from the microbiome enhances Arthrocnemum macrostachyum metal accumulation and tolerance Full text
2017
Navarro-Torre, Salvadora | Barcia-Piedras, José M. | Caviedes, Miguel A. | Pajuelo, Eloísa | Redondo-Gómez, Susana | Rodríguez-Llorente, Ignacio D. | Mateos-Naranjo, Enrique
Bioaugmentation with bacteria selected from the microbiome enhances Arthrocnemum macrostachyum metal accumulation and tolerance Full text
2017
Navarro-Torre, Salvadora | Barcia-Piedras, José M. | Caviedes, Miguel A. | Pajuelo, Eloísa | Redondo-Gómez, Susana | Rodríguez-Llorente, Ignacio D. | Mateos-Naranjo, Enrique
A glasshouse experiment was designed to investigate the role of bacterial consortia isolated from the endosphere (CE) and rhizosphere (CR) of Arthrocnemum macrostachyum on its metal uptake capacity and tolerance in plants grown in metal polluted sediments. A. macrostachyum plants were randomly assigned to three bioaugmentation treatments (CE, CR and without inoculation) during 120days. Bioaugmentation with both bacterial consortia enhanced A. macrostachyum capacity to accumulate ions in its roots, while shoot ions concentration only increased with CE treatment. Furthermore bioaugmentation ameliorated the phytotoxicity levels, which was reflected in an increment of plant growth of 59 and 113% for shoots and 52 and 98% for roots with CE and CR treatments, respectively. This effect was supported by bacteria beneficial effect on photochemical apparatus and the modulation of its oxidative stress machinery. These findings indicated that bacteria selected from the microbiome can be claimed to improve A. macrostachyum metal remediation efficiency.
Show more [+] Less [-]Bioaugmentation with bacteria selected from the microbiome enhances Arthrocnemum macrostachyum metal accumulation and tolerance Full text
2017
Navarro Torre, Salvadora | Barcia Piedras, José María | Caviedes Formento, Miguel Ángel | Pajuelo Domínguez, Eloísa | Redondo Gómez, Susana | Rodríguez Llorente, Ignacio David | Mateos Naranjo, Enrique | Universidad de Sevilla. Departamento de Microbiología y Parasitología | Universidad de Sevilla. Departamento de Biología Vegetal y Ecología | Junta de Andalucía | Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA) | Ministerio de Economía y Competitividad (MINECO). España
A glasshouse experiment was designed to investigate the role of bacterial consortia isolated from the endosphere (CE) and rhizosphere (CR) of Arthrocnemum macrostachyum on its metal uptake capacity and tolerance in plants grown in metal polluted sediments. A. macrostachyum plants were randomly assigned to three bioaugmentation treatments (CE, CR and without inoculation) during 120 days. Bioaugmentation with both bacterial consortia enhanced A. macrostachyum capacity to accumulate ions in its roots, while shoot ions concentration only increased with CE treatment. Furthermore bioaugmentation ameliorated the phytotoxicity levels, which was reflected in an increment of plant growth of 59 and 113% for shoots and 52 and 98% for roots with CE and CR treatments, respectively. This effect was supported by bacteria beneficial effect on photochemical apparatus and the modulation of its oxidative stress machinery. These findings indicated that bacteria selected from the microbiome can be claimed to improve A. macrostachyum metal remediation efficiency.
Show more [+] Less [-]Biomarker responses of Cu-induced toxicity in European seabass Dicentrarchus labrax: Assessing oxidative stress and histopathological alterations Full text
2017
Díaz-de-Alba, M. | Canalejo Raya, A. | Granado-Castro, M.D. | Oliva Ramírez, M. | El Mai, B. | Córdoba García, F. | Troyano-Montoro, M. | Espada-Bellido, E. | Torronteras Santiago, R. | Galindo-Riaño, M.D.
Biomarker responses of Cu-induced toxicity in European seabass Dicentrarchus labrax: Assessing oxidative stress and histopathological alterations Full text
2017
Díaz-de-Alba, M. | Canalejo Raya, A. | Granado-Castro, M.D. | Oliva Ramírez, M. | El Mai, B. | Córdoba García, F. | Troyano-Montoro, M. | Espada-Bellido, E. | Torronteras Santiago, R. | Galindo-Riaño, M.D.
A comprehensive approach to chemical accumulation and biological effects of short-term Cu exposure in juveniles of European seabass (Dicentrarchus labrax) has been achieved. Fish were exposed to 0.01–10mgL−1 nominal Cu concentrations for 24–96h. Metal concentrations in water and gills, liver, muscle and brain tissues were studied along with oxidative stress biomarkers (superoxide dismutase, catalase, glutathione peroxidase, lipid peroxidation). Induction of oxidative damage was observed in all the organs with differential antioxidant responses; gills appearing as the most sensitive from low environmentally water Cu concentrations as 0.01mgL−1. Histopathological alterations were also observed in liver and gills, even without a significant Cu accumulation.The results show that the combination of oxidative stress parameters, particularly lipid peroxidation and glutathione peroxidase activities, and histopathological alterations provide a good model fish and reliable early biomarkers for monitoring Cu pollution in seawater and might call for the protection agencies to revise the Cu environmental standards.
Show more [+] Less [-]Biomarker responses of Cu-induced toxicity in European seabass Dicentrarchus labrax: assessing oxidative stress and histopathological alterations Full text
2017
Díaz de Alba, Margarita Isabel | Canalejo Raya, Antonio | Granado Castro, María Dolores | Oliva Ramírez, Milagrosa | El Mai, Bahija | Córdoba García, Francisco | Troyano Montoro, Miriam | Espada Bellido, Estrella | Torronteras Santiago, Rafael | Galindo Riaño, María Dolores | Química Analítica
A comprehensive approach to chemical accumulation and biological effects of short-term Cu exposure in juveniles of European seabass (Dicentrarchus labrax) has been achieved. Fish were exposed to 0.01–10 mg L− 1 nominal Cu concentrations for 24–96 h. Metal concentrations in water and gills, liver, muscle and brain tissues were studied along with oxidative stress biomarkers (superoxide dismutase, catalase, glutathione peroxidase, lipid peroxidation). Induction of oxidative damage was observed in all the organs with differential antioxidant responses; gills appearing as the most sensitive from low environmentally water Cu concentrations as 0.01 mg L− 1. Histopathological alterations were also observed in liver and gills, even without a significant Cu accumulation. The results show that the combination of oxidative stress parameters, particularly lipid peroxidation and glutathione peroxidase activities, and histopathological alterations provide a good model fish and reliable early biomarkers for monitoring Cu pollution in seawater and might call for the protection agencies to revise the Cu environmental standards.
Show more [+] Less [-]Microplastics effects in Scrobicularia plana Full text
2017
Ribeiro, Francisca | Garcia, Ana R. | Pereira, Beatriz P. | Fonseca, María | Mestre, Nélia C. | Fonseca, Tainá G. | Ilharco, Laura M. | Bebianno, Maria João
Microplastics effects in Scrobicularia plana Full text
2017
Ribeiro, Francisca | Garcia, Ana R. | Pereira, Beatriz P. | Fonseca, María | Mestre, Nélia C. | Fonseca, Tainá G. | Ilharco, Laura M. | Bebianno, Maria João
One of the most common plastics in the marine environment is polystyrene (PS) that can be broken down to micro sized particles. Marine organisms are vulnerable to the exposure to microplastics. This study assesses the effects of PS microplastics in tissues of the clam Scrobicularia plana. Clams were exposed to 1mgL−1 (20μm) for 14days, followed by 7days of depuration. A qualitative analysis by infrared spectroscopy in diffuse reflectance mode period detected the presence of microplastics in clam tissues upon exposure, which were not eliminated after depuration. The effects of microplastics were assessed by a battery of biomarkers and results revealed that microplastics induce effects on antioxidant capacity, DNA damage, neurotoxicity and oxidative damage. S. plana is a significant target to assess the environmental risk of PS microplastics.
Show more [+] Less [-]Microplastics effects in Scrobicularia plana Full text
2017
Ribeiro, Francisca | Garcia, Ana | Pereira, Beatriz P. | Fonseca, Maria | Mestre, Nélia | Fonseca, Tainá | Ilharco, Laura M. | Bebianno, Maria João
One of the most common plastics in the marine environment is polystyrene (PS) that can be broken down to micro sized particles. Marine organisms are vulnerable to the exposure to microplastics. This study assesses the effects of PS microplastics in tissues of the clam Scrobicularia plana. Clams were exposed to 1mgL-1(20μm) for 14days, followed by 7days of depuration. A qualitative analysis by infrared spectroscopy in diffuse reflectance mode period detected the presence of microplastics in clam tissues upon exposure, which were not eliminated after depuration. The effects of microplastics were assessed by a battery of biomarkers and results revealed that microplastics induce effects on antioxidant capacity, DNA damage, neurotoxicity and oxidative damage. S. plana is a significant target to assess the environmental risk of PS microplastics. | info:eu-repo/semantics/publishedVersion
Show more [+] Less [-]Microplastics in coastal environments of the Arabian Gulf Full text
2017
Abayomi, Oyebamiji Abib | Range, Pedro | Al-Ghouti, Mohammad A. | Obbard, Jeffrey Philip | Almeer, Saeed Hashim | Ben-Hamadou, Radhouane
Microplastics in coastal environments of the Arabian Gulf Full text
2017
Abayomi, Oyebamiji Abib | Range, Pedro | Al-Ghouti, Mohammad A. | Obbard, Jeffrey Philip | Almeer, Saeed Hashim | Ben-Hamadou, Radhouane
Eight sandy beaches along the coastline of Qatar and four sea surface stations on the eastern coast, adjacent to Doha Bay, were surveyed between December 2014 and March 2015. Microplastics, mainly low density polyethylene and polypropylene, were found in all samples of sediments and seawater. Blue fibers, ranging between 1 and 5mm, were the dominant type of particle present. Abundances on the sea surface varied between 4.38×104 and 1.46×106particles·km−2, with the highest values being consistently found 10km offshore, suggesting the presence of a convergence zone. No significant temporal variability was detected for sea surface samples. The concentration of microplastics in intertidal sediments varied between 36 and 228particlesm−2, with no significant differences among the 8 beaches examined. These results show the pervasiveness of microplastic pollution in coastal environments of the Arabian Gulf. Potential local sources and sinks for microplastics are discussed.
Show more [+] Less [-]Microplastics in coastal environments of the Arabian Gulf Full text
2017
Abayomi, Oyebamiji Abib | Range, Pedro | Al-Ghouti, Mohammad A. | Obbard, Jeffrey Philip | Almeer, Saeed Hashim | Ben-Hamadou, Radhouane
Eight sandy beaches along the coastline of Qatar and four sea surface stations on the eastern coast, adjacent to Doha Bay, were surveyed between December 2014 and March 2015. Microplastics, mainly low density polyethylene and polypropylene, were found in all samples of sediments and seawater. Blue fibers, ranging between 1 and 5 mm, were the dominant type of particle present. Abundances on the sea surface varied between 4.38 × 104 and 1.46 × 106 particles·km− 2, with the highest values being consistently found 10 km offshore, suggesting the presence of a convergence zone. No significant temporal variability was detected for sea surface samples. The concentration of microplastics in intertidal sediments varied between 36 and 228 particles m− 2, with no significant differences among the 8 beaches examined. These results show the pervasiveness of microplastic pollution in coastal environments of the Arabian Gulf. Potential local sources and sinks for microplastics are discussed. | We would like to thank Mariem Amor Safi for her support during sampling activities. This work was funded by Qatar University , through the Department of Biological and Environmental Sciences ( QUUG-CAS-DBES-13/14-9 ) and the College of Arts and Sciences ( QUST-CAS-SPR-14\15-30 ), and supported by the Environmental Science Center . | Scopus
Show more [+] Less [-]Underestimation of chemical contamination in marine fish muscle tissue can be reduced by considering variable wet:dry weight ratios Full text
2017
Cresson, Pierre | Travers-Trolet, Morgane | Rouquette, Manuel | Timmerman, Charles-André | Giraldo, Carolina | Lefebvre, Sébastien | Ernande, Bruno
Underestimation of chemical contamination in marine fish muscle tissue can be reduced by considering variable wet:dry weight ratios Full text
2017
Cresson, Pierre | Travers-Trolet, Morgane | Rouquette, Manuel | Timmerman, Charles-André | Giraldo, Carolina | Lefebvre, Sébastien | Ernande, Bruno
Whether considered as a risk for human health or as ecological tracers, contaminants' concentrations measured in fish muscles are commonly expressed relative to wet or dry mass. Comparison of results required conversion factors (CF) but accurate values are scarce and case-specific. The present paper is aimed at investigating errors linked with the use of the theoretical value. Muscles dry and wet masses were measured in 15 fish species to determine the actual CF. Most CF were lower than the theoretical wet:dry ratio of 5 classically used, with variations at individual and species level. Muscle lipid content (inferred by C/N ratios) was a crucial factor explaining discrepancies, claiming for caution when working with lipid-rich species. The observed variability demonstrated that using the theoretical CF may be inaccurate, when actual CF largely differs from the theoretical value. Dedicated measurement is the better approach when accuracy is required.
Show more [+] Less [-]Underestimation of chemical contamination in marine fish muscle tissue can be reduced by considering variable wet:dry weight ratios Full text
2017
Cresson, Pierre | Travers-trolet, Morgane | Rouquette, Manuel | Timmerman, Charles-andre | Giraldo, Carolina | Lefebvre, Sebastien | Ernande, Bruno
Whether considered as a risk for human health or as ecological tracers, contaminants' concentrations measured in fish muscles are commonly expressed relative to wet or dry mass. Comparison of results required conversion factors (CF) but accurate values are scarce and case-specific. The present paper is aimed at investigating errors linked with the use of the theoretical value. Muscles dry and wet masses were measured in 15 fish species to determine the actual CF. Most CF were lower than the theoretical wet:dry ratio of 5 classically used, with variations at individual and species level. Muscle lipid content (inferred by C/N ratios) was a crucial factor explaining discrepancies, claiming for caution when working with lipid-rich species. The observed variability demonstrated that using the theoretical CF may be inaccurate, when actual CF largely differs from the theoretical value. Dedicated measurement is the better approach when accuracy is required.
Show more [+] Less [-]