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Ecological quality status of the Adriatic coastal waters evaluated by the organotin pollution biomonitoring Texte intégral
2017
Erdelez, A. | Furdek Turk, M. | Štambuk, A. | Župan, I. | Peharda, M.
The aim of this study was to evaluate the post-legislation change in tributyltin (TBT) pollution at Croatian Adriatic coast. Gastropod Hexaplex trunculus and sediments were collected, nearly 10years after TBT based antifouling paints were banned, at 12 locations along the coast where a previous study was conducted in 2005. The study showed a decline of TBT levels over the investigated period, although all gastropods populations were highly affected by imposex meaning that prohibition did not result in the recovery of populations. The further aim was to propose the Ecological Quality Ratio (EQR) boundaries for potential use of H. trunculus as a principal bioindicator in the assessment of the ecological status of the Mediterranean regarding TBT pollution, under the Water Framework Directive (WFD). According to the proposed EQR classes, the WFD target for achieving the Good ecological status of the marine environment by 2015 was not reached.
Afficher plus [+] Moins [-]Exposure to crack cocaine causes adverse effects on marine mussels Perna perna Texte intégral
2017
Maranho, L.A. | Fontes, M.K. | Kamimura, A.S.S. | Nobre, C.R. | Moreno, B.B. | Pusceddu, F.H. | Cortez, F.S. | Lebre, D.T. | Marques, J.R. | Abessa, D.M.S. | Ribeiro, D.A. | Pereira, C.D.S.
Our study aimed to evaluate crack cocaine effects in different life stages of the marine mussel Perna perna. For this purpose, fertilization rate, embryo-larval development, lysosomal membrane stability and DNA strand breaks were assessed. Effect concentrations in gametes and in larval development were found after 1h (IC50=23.53mg·L−1) and 48h (IC50=16.31mg·L−1), respectively. The highest tested concentration showing no acute toxicity (NOEC) was 10mg·L−1, while the lowest observed effect concentration (LOEC) was 20mg·L−1. NOEC concerning embryo-larval development was 0.625mg·L−1, while the LOEC was 1.25mg·L−1. Cyto-genotoxic effects were evidenced in mussels exposed to crack cocaine concentrations ranging from 5 to 500μg·L−1. Our results report the first data on effects of an illicit drug to marine organisms and should encourage further ecotoxicological studies of these contaminants of emerging concern in coastal ecosystems.
Afficher plus [+] Moins [-]Elevated mercury concentrations in the feathers of grey-faced petrels (Pterodroma gouldi) in New Zealand Texte intégral
2017
Lyver, P.O'.B. | Aldridge, S.P. | Gormley, A.M. | Gaw, S. | Webb, S. | Buxton, R.T. | Jones, C.J.
Our objective was to measure the concentrations of Hg, As, Cd, Co, Cr, Cu, Pb, Sb, V and Zn in the body feathers of grey-faced petrel (Pterodroma gouldi), fluttering shearwater (Puffinus gavia), little shearwater (Puffinus assimilis) and common diving petrel (Pelecanoides urinatrix) from breeding colonies in New Zealand between 2006 and 2013. The mean Hg concentration (36.48ppm; SD=9.59) in grey-faced petrel feathers was approximately 8.5 to 14 times that detected in the other three species sampled. We detected no trend or differences in Hg concentrations in grey-faced petrels over the 8years of this study, but Hg concentrations varied between breeding colonies although there was no strong relationship with latitude. The elevated Hg concentrations detected in grey-faced petrels could pose a risk to the breeding performance of grey-faced petrels and the customary harvest of chicks by Māori (New Zealand's indigenous peoples).
Afficher plus [+] Moins [-]Tungsten Contamination of Soils and Sediments: Current State of Science Texte intégral
2017
Datta, Saugata | Vero, Sara E. | Hettiarachchi, Ganga M. | Johannesson, Karen
Tungsten (W) is commonly employed as a non-toxic alternative to lead in a broad variety of industrial and military applications. However, correlations between environmental contamination through soil, water and airborne pathways, and biological effects such as epithelial damage, bioaccumulation, and trophic mobility, have led to its classification as an “emerging contaminant.” Of particular concern are recent clusters of childhood leukemia and lung cancer in the vicinity of tungsten mines and processing facilities. High environmental tungsten availability has also been associated with altered thyroid function, cardiovascular disease, and prolonged elevation of concentrations in blood, breath, and urine. Tungsten’s use as a replacement for lead (Pb) in military munitions has resulted in leaching of tungsten into soil and into soft tissues in which bullet fragments are embedded. Despite these associations, no consensus has been reached regarding the mechanisms by which tungsten affects the human body. Particularly confounding are the issues of co-toxicity with other known contaminants such as arsenic, cobalt, and cadmium, and differences resulting from the various methods of ingestion. The present paper summarizes the current behavior of tungsten in the environment, its occurrence within the pedosphere, biosphere, and atmosphere, and discusses its potential effects on exposed biota (especially humans). In particular, knowledge gaps are identified regarding the biological mechanisms of tungsten-related disease, which urgently require further elucidation in order to develop appropriate policies and management practices for the use of this element.
Afficher plus [+] Moins [-]Impact of an experimental eutrophication on the processes of bioerosion on the reef: One Tree Island, Great Barrier Reef, Australia Texte intégral
2017
Chazottes, Veronique | Hutchings, Pat | Osorno, Alicia
The components of bioerosion were investigated during ENCORE (The Effect of Nutrient Enrichment on Coral Reefs) over 2years of controlled additions of dissolved inorganic nitrogen and phosphorus. The study was carried out at One Tree Island, southern Great Barrier Reef, Australia. Rates of microbioerosion and external erosion by grazing were significantly higher at the enriched sites than at the control sites. Rates of accretion by coralline algae were also significantly higher at enriched sites. In contrast, rates of macroboring were not significantly different between enriched and control sites.This study highlights the importance of improving water quality on the reef to reduce rates of bioerosion given that quantities of dead coral substrates have recently substantially increased as a result of coral bleaching (Hughes et al., 2015) and several Crown of Thorns plagues (Fabricius et al., 2010; De'ath et al., 2012), on the Great Barrier Reef.
Afficher plus [+] Moins [-]Environmental Ground-Borne Noise and Vibration from Urban Light Rail Transportation During Construction and Operation Texte intégral
2017
Vogiatzis, Konstantinos E. | Kouroussis, Georges
Environmental vibration and ground-borne noise from light rail transport (LRT) networks consists a major impact on the urban environment. Since experiments are often difficult to obtain and to interpret especially for environmental vibration, designers and researchers generally resource numerical model to assess vibration levels and understand the complex mechanism of generation and propagation of ground vibration. In this paper, some highlights are provided on vehicle/track/soil modeling for railway-induced ground vibration, including the proper definitions of each of these subsystems. The nature of the wheel/rail interaction is also important, especially in urban area, so a case study demonstrates that local unevenness are important sources of vibrations. On the other hand, specialized prediction models and dose-response relationships for airborne rail noise during operation and construction phases of urban light rail transport networks (both underground and surficial) are needed to be evaluated, in order to quantify the impact of the technical characteristics of the noise source, the operation mode with emphasis to speed, the propagation, the implementation of quiet facades, and the number and distribution of high-level noise events. In the present paper, two distinct case studies are presented in order to emphasize the need and the necessity of using proper tools to predict, access, monitor, and evaluate the environmental impact of LRTs to the urban acoustic environment: (a) the new Brussels Regional Express Network and (b) the new Athens Metro Line 3 extension to Piraeus port in an underground tunnel (length 7.6 km).
Afficher plus [+] Moins [-]Boat anchoring pressure on coastal seabed: Quantification and bias estimation using AIS data Texte intégral
2017
Deter, Julie | Lozupone, Xavier | Inacio, Adrien | Boissery, Pierre | Holon, Florian
Global shipping is economically important, but has many adverse environmental effects. Anchoring contributes greatly to this adverse impact, as it is responsible for mechanical disturbance of highly sensitive marine habitats. Recovery of these ecosystems is limited by slow regrowth. Anchoring pressure on coastal seabed habitats was estimated using AIS (Automatic Identification System) data along 1800km of Mediterranean coastline between 2010 and 2015. A comparison with field observations showed that these results were most consistent for large boats (>50m). An analysis of AIS data coupled with a seabed map showed that around 30% of the habitats between 0 and −80m exhibited anchoring pressure. Posidonia oceanica seagrass beds were the most impacted habitat in terms of duration. This methodology efficiently estimates spatial and temporal anchoring pressure principally due to large boats and should interest managers of marine protected areas as much as coastline managers.
Afficher plus [+] Moins [-]Distribution, sources, and ecological risk assessment of polycyclic aromatic hydrocarbons in surface sediments from the Nantong Coast, China Texte intégral
2017
Liu, Na | Li, Xian | Zhang, Daolai | Liu, Qiang | Xiang, Lihui | Liu, Ke | Yan, Dongyun | Li, Yue
The distribution, sources, and ecological risk assessment of 16 polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the Nantong coast in China were investigated. The results indicated that the total concentrations of the 16 PAHs in the surface sediments from the study area ranged from 1.4 to 87.1ngg−1 dw (mean value 19.9ngg−1 dw), which were generally low compared to the adjacent offshore area and other coastal zones around the world. The selected PAH ratios and the principal components analysis for each site showed that petroleum combustion and petrogenic pollution (mainly caused by petroleum spills) were the dominant PAHs sources in the surface sediments of the coast. The ecological risk assessment indicated that most of the individual PAHs had few negative effects in this area.
Afficher plus [+] Moins [-]Evaluation of sediment contamination by monoaromatic hydrocarbons in the coastal lagoons of Gulf of Saros, NE Aegean Sea Texte intégral
2017
Ünlü, Selma | Alpar, Bedri
The concentrations and distribution of monoaromatic hydrocarbons (benzene, toluene, ethyl benzene and the sum of m-, p- and o-, xylenes) were determined in the sediments of coastal lagoons of the Gulf of Saros, using a static headspace GC–MS. The total concentrations of BTEX compounds ranged from 368.5 to below detection limit 0.6μgkg−1 dw, with a mean value of 61.5μgkg−1 dw. The light aromatic fraction of m-, p-xylene was the most abundant compound (57.1% in average), and followed by toluene (38.1%)>ethylbenzene (4.1%)>o-xylene (2.5%)>benzene (1.1%). The factor analysis indicated that the levels and distribution of BTEX compounds depend on the type of contaminant source (mobile/point), absorbance of compounds in sediment, and mobility of benzene compound and degradation processes. Point sources are mainly related to agricultural facilities and port activities while the dispersion of compounds are related with their solubility, volatility and effect of sea/saline waters on lagoons.
Afficher plus [+] Moins [-]Characterization of Enterococcus species isolated from marine recreational waters by MALDI-TOF MS and Rapid ID API® 20 Strep system Texte intégral
2017
Christ, Ana Paula Guarnieri | Ramos, Solange Rodrigues | Cayô, Rodrigo | Gales, Ana Cristina | Hachich, Elayse Maria | Sato, Maria Inês Zanoli
MALDI-TOF Mass Spectrometry Biotyping has proven to be a reliable method for identifying bacteria at the species level based on the analysis of the ribosomal proteins mass fingerprint. We evaluate the usefulness of this method to identify Enterococcus species isolated from marine recreational water at Brazilian beaches. A total of 127 Enterococcus spp. isolates were identified to species level by bioMérieux's API® 20 Strep and MALDI-TOF systems. The biochemical test identified 117/127 isolates (92%), whereas MALDI identified 100% of the isolates, with an agreement of 63% between the methods. The 16S rRNA gene sequencing of isolates with discrepant results showed that MALDI-TOF and API® correctly identified 74% and 11% of these isolates, respectively. This discrepancy probably relies on the bias of the API® has to identify clinical isolates. MALDI-TOF proved to be a feasible approach for identifying Enterococcus from environmental matrices increasing the rapidness and accuracy of results.
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