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Phytochelatins and monothiols in salt marsh plants and their relation with metal tolerance Texte intégral
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 Texte intégral
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.
Afficher plus [+] Moins [-]Phytochelatins and monothiols in salt marsh plants and their relation with metal tolerance Texte intégral
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
Afficher plus [+] Moins [-]Mercury, arsenic, cadmium and lead in two commercial shark species (Sphyrna lewini and Caraharinus porosus) in Trinidad and Tobago Texte intégral
2017
Mohammed, Azad | Mohammed, Terry
Sharks are long-lived apex predators which can accumulate toxic metals such as mercury and arsenic. Samples of Sphyrna lewini and Carcharinus porosus were collected from two commercial fish landing sites in Trinidad. Heavy metal concentrations were determined in the muscle, dorsal fin, vertebrae and liver using atomic absorption spectrometric. The provisional tolerable weekly intake (PTWI) and target hazard quotient (THQ) were determined to assess the potential health risks to consumers. Mercury levels ranged between 74–1899μg/kg in S. lewini and 67–3268μg/kg in C. porosus. Arsenic levels ranged between 144–2309μg/kg in S. lewini and 762–6155μg/kg in C. porosus. Cadmium levels generally ranged between 0.27–27.29mg/kg in S. lewini and 0.6–29.89mg/kg in C. porosus. Lead levels generally ranged between 0.14 and 208.81mg/kg in S. lewini while C. porosus levels ranged between 0.30 and 459.94mg/kg. The PTWI and THQ values suggest that consumption of these shark species can therefore be a major source of exposure to lead, cadmium, arsenic and mercury in humans and is likely to have potential health risk over long term exposure.
Afficher plus [+] Moins [-]Identifying the source of petroleum pollution in sediment cores of southwest of the Caspian Sea using chemical fingerprinting of aliphatic and alicyclic hydrocarbons Texte intégral
2017
Shirneshan, Golshan | Bakhtiari, Alireza Riyahi | Memariani, Mahmoud
In this study, the concentration and sources of aliphatic and petroleum markers were investigated in 105 samples of Anzali, Rezvanshahr and Astara cores from the southwest of Caspian Sea. Petroleum importation was diagnosed as a main source in most depths of cores by the results of unresolved complex mixture, carbon preference index and hopanes and steranes. From the chemical diagnostic parameters, petroleum inputs in sediment of cores were determined to be different during years and the sources of hydrocarbons in some sections differed than Anzali and Turkmenistan and Azerbaijan oils. Diagenic ratios in most sediments of upper and middle sections in Astara core were determined to be highly similar to those of Azerbaijan oil, while the presence of Turkmenistan and Anzali oils were detected in a few sections of Anzali and Rezvanshahr cores and only five layers of downer section in Anzali core, respectively.
Afficher plus [+] Moins [-]Acute toxicity of organic antifouling biocides to phytoplankton Nitzschia pungens and zooplankton Artemia larvae Texte intégral
2017
Jung, S.M. | Bae, J.S. | Kang, S.G. | Son, J.S. | Jeon, J.H. | Lee, H.J. | Jeon, J.Y. | Sidharthan, M. | Ryu, SH | Shin, H.W.
The toxicity of the antifouling biocides Irgarol 1051, Diuron, Chlorothalonil, Dichlofluanid, Sea-nine 211, Copper pyrithione, Zinc pyrithione, Ziram and Zineb were evaluated on Nitzschia pungens and Artemia larvae. Results showed that EC50 for Irgarol 1051 was 0.586μgl−1 was the strongest effect on N. pungens following by Copper pyrithione (4.908μgl−1), Ziram (5.421μgl−1), Zinc pyrithione (5.513μgl−1), Diuron (6.640μgl−1), Zineb (232.249μgl−1), Sea-nine 211(267.368μgl−1), Chlorothalonil (360.963μgl−1) and Dichlofluanid (377.010μgl−1) in 96h. In Artemia larvae, the biocides were evaluated the LC50 for larval survivals at 48h. Sea-nine 211 and Copper pyrithione were 0.318 and 0.319mgl−1. Chlorothalonil, Zinc pyrithione and Ziram were 2.683, 3.147 and 4.778mgl−1. Irgarol 1051, Diuron, Zineb and Dichlofluanid were 9.734, 30.573, 41.170 and 154.944mgl−1. These results provide baseline data concerning the toxicity of antifouling biocides against marine environment.
Afficher plus [+] Moins [-]Talitrus saltator as a biomonitor: An assessment of trace element contamination on an urban coastline gradient Texte intégral
2017
Morrison, Liam | Bennion, Matthew | McGrory, Ellen | Hurley, William | Johnson, M.P.
This study reports the first ever application of the trace element pollution index (TEPI) along a coastal, urban gradient using trace element concentrations (Ti, Mn, Co, Cu, As, Mo, Ag, Cd, Pb, Cr, Fe, Zn and Se) in the amphipod crustacean Talitrus saltator. Samples were collected from 10 sites in Galway Bay (Ireland) and concentrations of Pb showed the greatest spatial variation, likely due to the proximity of some sites to a former landfill and busy harbour. The TEPI used alongside the quartile method allowed for the assigning of sites to contamination level categories. Mapping these class levels allowed for straightforward visualisation of trace element contamination along the urban gradient. In addition, this study presents trace elements levels in T. saltator form the Atlantic Coast of Europe for the first time and the concentrations observed were comparatively lower than previously reported for T. saltator from the Baltic and Mediterranean seas.
Afficher plus [+] Moins [-]Ecological risk assessment of a coastal zone in Southern Vietnam: Spatial distribution and content of heavy metals in water and surface sediments of the Thi Vai Estuary and Can Gio Mangrove Forest Texte intégral
2017
Costa-Böddeker, Sandra | Hoelzmann, Philipp | Thuyên, Lê Xuân | Huy, Hoang Duc | Nguyễn, Hoàng Anh | Richter, Otto | Schwalb, Antje
Enrichment of heavy metals was assessed in the Thi Vai Estuary and in the Can Gio Mangrove Forest (SE, Vietnam). Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn contents in water and in sediments were measured. Total organic carbon, nitrogen, phosphorus and C/N ratios were determined. Cu and Cr values were higher than threshold effect level of toxicity, while Ni exceeded probable effect level, indicating the risk of probable toxicity effects. Enrichment factors (EF), contamination factor (CF) and Geo-accumulation index (I-geo) were determined. CF reveals moderate to considerable pollution with Cr and Ni. EF suggests anthropogenic sources of Cr, Cu and Ni. I-geo indicates low contamination with Co, Cu and Zn and moderate contamination with Cr and Ni. Overall metal contents were lower than expected for this highly industrialized region, probably due to dilution, suggesting that erosion rates and hydrodynamics may also play a role in metal contents distribution.
Afficher plus [+] Moins [-]Ports and pests: Assessing the threat of aquatic invasive species introduced by maritime shipping activity in Cuba Texte intégral
2017
O'Brien, Charleen E. | Johnston, Matthew W. | Kerstetter, David W.
Aquatic invasive species (AIS) are biological pollutants that cause detrimental ecological, economic, and human-health effects in their introduced communities. With increasing globalization through maritime trade, ports are vulnerable to AIS exposure via commercial vessels. The Cuban Port of Mariel is poised to become a competitive transshipment hub in the Caribbean and the intent of this study was to evaluate present and potential impacts AIS pose with the likely future increase in shipping activity. We utilized previous assessment frameworks and publicly accessible information to rank AIS by level of threat. Fifteen AIS were identified in Cuba and one, the Asian green mussel Perna viridis (Linnaeus, 1758), had repeated harmful economic impacts. Five species associated with trade partners of Port Mariel were considered potentially detrimental to Cuba if introduced through shipping routes. The results presented herein identify species of concern and emphasize the importance of prioritizing AIS prevention and management within Cuba.
Afficher plus [+] Moins [-]The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms Texte intégral
2017
Kühn, Susanne | Werven, Van, Bernike | Oyen, Van, Albert | Meijboom, André | Bravo Rebolledo, Elisa L. | Franeker, Van, Jan A.
The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms
2017
Kühn, Susanne | Werven, Van, Bernike | Oyen, Van, Albert | Meijboom, André | Bravo Rebolledo, Elisa L. | Franeker, Van, Jan A.
In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife.
Afficher plus [+] Moins [-]The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms Texte intégral
2017
Kuhn, Susanne | van Werven, Bernike | van Oyen, Albert | Meijboom, André | Bravo Rebolledo, Elisa L. | van Franeker, Jan A.
In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife.
Afficher plus [+] Moins [-]Spatiotemporal variations in metal accumulation, RNA/DNA ratio and energy reserve in Perna viridis transplanted along a marine pollution gradient in Hong Kong Texte intégral
2017
Yeung, Jamius W.Y. | Zhou, Guang-Jie | Leung, Kenneth M.Y.
We examined spatiotemporal variations of metal levels and three growth related biomarkers, i.e., RNA/DNA ratio (RD), total energy reserve (Et) and condition index (CI), in green-lipped mussels Perna viridis transplanted into five locations along a pollution gradient in the marine environment of Hong Kong over 120days of deployment. There were significant differences in metal levels and biomarker responses among the five sites and six time points. Mussels in two clean sites displayed better CI and significantly lower levels of Ag, Cu, Pb and Zn in their tissues than the other sites. Temporal patterns of RD in P. viridis were found to be site-specific. Across all sites, Et decreased in P. viridis over the deployment period, though the rate of decrease varied significantly among the sites. Therefore, temporal variation of biomarkers should be taken to consideration in mussel-watch programs because such information can help discriminate pollution-induced change from natural variation.
Afficher plus [+] Moins [-]Trace metals in sediments and benthic animals from aquaculture ponds near a mangrove wetland in Southern China Texte intégral
2017
Wu, Hao | Liu, Jinling | Bi, Xiangyang | Lin, Guanghui | Feng, Christopher C | Li, Zhengjie | Qi, Fei | Zheng, Tianling | Xie, Liqi
In this study, we measured the concentrations of trace metals (Cr, Cu, Zn, As, Cd, Pb and Hg) in typical cultured animals (crabs, clams, and shrimps) and sediments from aquaculture ponds nearby mangrove wetlands in Zhangjiang estuary, China. The contents of Cr, Cu, Cd, and Pb in mangrove sediments were significantly higher than those in pond sediments, while an inverse distribution was observed for Zn, As, and Hg. Significantly higher concentrations of trace metals were found in clams from the mangrove mudflats compared to those from the aquaculture ponds. The sources of trace metals in the clams were primarily from organic fertilizer, whereas those in the shrimp were from contaminated sediment. The results of geo-accumulation index and the ecological risk assessment indicated that the aquaculture ponds near the mangrove wetlands in this subtropical estuary posed a special risk of endogenous and exogenous trace metal pollution to nearby systems.
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