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Selective detection of chloramphenicol based on molecularly imprinted solid-phase extraction in seawater from Jiaozhou Bay, China 全文
2018
Lian, Ziru | Wang, Jiangtao
This study highlights an efficient sample pre-treatment method for preconcentration and detection of chloramphenicol in marine water using molecularly imprinted solid-phase extraction (MISPE). Chloramphenicol molecularly imprinted microspheres were prepared and evaluated on the base of morphology, capacity and selectivity. The imprinted microspheres exhibited specific recognition and high retention capability to chloramphenicol and were applied as special solid-phase extraction adsorbents. An off-line MISPE protocol has been optimized and a creative analytical method coupled to HPLC-DAD was successfully developed for the cleanup and determination of chloramphenicol in seawater samples. Method performance was satisfactory with recoveries ranging from 81 to 90% and relative standard deviation (RSD) was <4.93% (n = 3). Accuracy of the method was assessed at three spiking concentration levels and the limit of detection was 5 ng L⁻¹. Finally, five seawater samples from Jiaozhou Bay of China were determined and the results showed that there was no chloramphenicol detected.
显示更多 [+] 显示较少 [-]Polycyclic aromatic hydrocarbon (PAH) accumulation in different common sole (Solea solea) tissues from the North Adriatic Sea peculiar impacted area 全文
2018
Frapiccini, Emanuela | Annibaldi, Anna | Betti, Mattia | Polidori, Piero | Truzzi, Cristina | Marini, Mauro
This study extends our knowledge of the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in marine organisms and investigates its possible determinants. PAH levels were measured in Solea solea tissue and in marine sediments collected from three areas of the northern Adriatic Sea characterized by different anthropic impacts (Venetian Lagoon, Po Delta, and fishing grounds off Chioggia). The possibility of differential PAH bioaccumulation in different tissues (muscle, liver and gills) was investigated by seeking relationships between mean individual and total PAH concentrations in tissue and sediment samples, the physicochemical properties of PAHs (rings and Kow), and some key biological variables (lipid content of tissues, body size, habitat). The present study demonstrated that the lipid content might not be the only determinant of PAH bioaccumulation in common sole tissues. The habitat characteristics, the tissue types and some physicochemical properties of compounds were closely related to PAH bioaccumulation.
显示更多 [+] 显示较少 [-]The need for a formalised system of Quality Control for environmental policy-science 全文
2018
Research science used to inform public policy decisions, herein defined as “Policy-Science”, is rarely subjected to rigorous checking, testing and replication. Studies of biomedical and other sciences indicate that a considerable fraction of published peer-reviewed scientific literature, perhaps half, has significant flaws. To demonstrate the potential failings of the present approaches to scientific Quality Control (QC), we describe examples of science associated with perceived threats to the Great Barrier Reef (GBR), Australia. There appears a serious risk of efforts to improve the health of the GBR being directed inefficiently and/or away from the more serious threats. We suggest the need for a new organisation to undertake quality reviews and audits of important scientific results that underpin government spending decisions on the environment. Logically, such a body could also examine policy science in other key areas where governments rely heavily upon scientific results, such as education, health and criminology.
显示更多 [+] 显示较少 [-]Development of ELISAs for the detection of vitellogenin in three marine fish from coastal areas of China 全文
2018
Li, Yuejiao | Wang, Jun | Zheng, Mingyi | Zhang, Yabin | Ru, Shaoguo
Estrogenic pollution has aroused great concern for its adverse effects on marine organisms. This study aimed to establish biomarker-based methods for detecting environmental estrogens using vitellogenin (Vtg) of teleost fishes inhabiting coastal areas of China. Firstly, Vtgs in marbled flounder (Pseudopleuronectes yokohamae), black rockfish (Sebastes schlegelii) and fat greenling (Hexagrammos otakii) were purified, characterized and used to prepare antibodies. Then, Vtg ELISA for each species was developed using purified Vtg and its antibody. Marbled flounder Vtg ELISA had a working range of 3.9–500 ng/mL and a detection limit of 2.1 ng/mL, and black rockfish Vtg ELISA had strong cross-reactivity with marbled flounder Vtg. Furthermore, Vtg induction in male marbled flounder exposed to pentadecafluorooctanoic acid (PFOA) was measured by developed ELISA. Plasma Vtg concentrations were significantly increased with PFOA concentrations in seawater and fish muscle. Therefore, Vtg ELISAs for these species might be useful tools for monitoring marine environmental estrogens.
显示更多 [+] 显示较少 [-]An ecological risk assessment model for Arctic oil spills from a subsea pipeline 全文
2018
Arzaghi, Ehsan | Abbassi, Rouzbeh | Garaniya, Vikram | Binns, Jonathan | K̲h̲ān, Faiṣal
There is significant risk associated with increased oil and gas exploration activities in the Arctic Ocean. This paper presents a probabilistic methodology for Ecological Risk Assessment (ERA) of accidental oil spills in this region. A fugacity approach is adopted to model the fate and transport of released oil, taking into account the uncertainty of input variables. This assists in predicting the 95th percentile Predicted Exposure Concentration (PEC95%) of pollutants in different media. The 5th percentile Predicted No Effect Concentration (PNEC5%) is obtained from toxicity data for 19 species. A model based on Dynamic Bayesian Network (DBN) is developed to assess the ecological risk posed to the aquatic community. The model enables accounting for the occurrence likelihood of input parameters, as well as analyzing the time-variable risk profile caused by seasonal changes. It is observed through the results that previous probabilistic methods developed for ERA can be overestimating the risk level.
显示更多 [+] 显示较少 [-]Amount, composition, and spatial distribution of floating macro litter along fixed trans-border transects in the Mediterranean basin 全文
2018
Arcangeli, Antonella | Campana, Ilaria | Angeletti, Dario | Atzori, Fabrizio | Azzolin, Marta | Carosso, Lara | Di Miccoli, Valentina | Giacoletti, Antonio | Gregorietti, Martina | Luperini, Cristina | Paraboschi, Miriam | Pellegrino, Giuliana | Ramazio, Martina | Sarà, Gianluca | Crosti, Roberto
Marine litter is a major source of pollution in the Mediterranean basin, but despite legislative requirements, scant information is available for the ongoing assessment of this threat.Using higher size classes as proxy for litter distribution, this study gave a synoptic estimation of the amount, composition, and distribution of floating macro-litter in the Mediterranean. The average amount of macro-litter was in a range of 2–5items/km2, with the highest in the Adriatic basin. Seasonal patterns were present in almost all study areas and were significant in the Ligurian Sea, Sardinian-Balearic basin, and Central Tyrrhenian Sea. Plastic accounted for >80% of litter in all areas and seasons, with the highest proportion in the Adriatic Sea, Ligurian Sea, and Sicilian-Sardinian Channels; in the Bonifacio Strait, Tyrrhenian Sea, and Sardinian-Balearic basin, litter composition was instead more diverse. Spatial analysis suggested an almost homogeneous distribution of litter without evident regular aggregation zones.
显示更多 [+] 显示较少 [-]An assessment of the microbial community in an urban fringing tidal marsh with an emphasis on petroleum hydrocarbon degradative genes 全文
2018
Ní Chadhain, Sinéad M. | Miller, Jarett L. | Dustin, John P. | Trethewey, Jeff P. | Jones, Stephen H. | Launen, Loren A.
Small fringing marshes are ecologically important habitats often impacted by petroleum. We characterized the phylogenetic structure (16S rRNA) and petroleum hydrocarbon degrading alkane hydroxylase genes (alkB and CYP 153A1) in a sediment microbial community from a New Hampshire fringing marsh, using alkane-exposed dilution cultures to enrich for petroleum degrading bacteria. 16S rRNA and alkB analysis demonstrated that the initial sediment community was dominated by Betaproteobacteria (mainly Comamonadaceae) and Gammaproteobacteria (mainly Pseudomonas), while CYP 153A1 sequences predominantly matched Rhizobiales. 24 h of exposure to n-hexane, gasoline, dodecane, or dilution culture alone reduced functional and phylogenetic diversity, enriching for Gammaproteobacteria, especially Pseudomonas. Gammaproteobacteria continued to dominate for 10 days in the n-hexane and no alkane exposed samples, while dodecane and gasoline exposure selected for gram-positive bacteria. The data demonstrate that small fringing marshes in New England harbor petroleum-degrading bacteria, suggesting that petroleum degradation may be an important fringing marsh ecosystem function.
显示更多 [+] 显示较少 [-]Structural and functional shifts of bacterioplanktonic communities associated with spatiotemporal gradients in river outlets of the subtropical Pearl River Estuary, South China 全文
2018
Mai, Yong-zhan | Lai, Zi-ni | Li, Xin-hui | Peng, Song-yao | Wang, Chao
In this study, we used high-throughput sequencing of 16S rRNA gene amplicons, to investigate the spatio-temporal variation in bacterial communities in surface-waters collected from eight major outlets of the Pearl River Estuary, South China. Betaproteobacteria were the most abundant class among the communities, followed by Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, and Acidimicrobiia. Generally, alpha-diversity increased in winter communities and the taxonomic diversity of bacterial communities differed with seasonal and spatial differences. Temperature, conductivity, salinity, pH and nutrients were the crucial environmental factors associated with shifts in the bacterial community composition. Furthermore, inferred community functions that were associated with amino acid, carbohydrate and energy metabolisms were lower in winter, whereas the relative abundance of inferred functions associated with membrane transport, bacterial motility proteins, and xenobiotics biodegradation and metabolism, were enriched in winter. These results provide new insights into the dynamics of bacterial communities within estuarine ecosystems.
显示更多 [+] 显示较少 [-]Floating plastics in Adriatic waters (Mediterranean Sea): From the macro- to the micro-scale 全文
2018
Zeri, C. | Adamopoulou, A. | Bojanić Varezić, D. | Fortibuoni, T. | Kovač Viršek, M. | Kržan, A. | Mandic, M. | Mazziotti, C. | Palatinus, A. | Peterlin, M. | Prvan, M. | Ronchi, F. | Siljic, J. | Tutman, P. | Vlachogianni, Th
Macro- and microplastics abundances were determined in the Adriatic Sea following the MSFD TG10 protocol. The studied areas included populated gulfs, river outlets and offshore waters in five Adriatic countries. The use of small ships enabled us to detect small sized plastics (2.5–5 cm) and record average macroplastics densities of 251 ± 601 items km−2, one order of magnitude higher than previously considered. Results from manta net tows for microplastics revealed an average abundance of 315,009 ± 568,578 items km−2 (217 ± 575 g km−2). We found significantly higher microplastics abundances in nearshore (≤4 km) than in offshore waters (>4 km) and this trend seems to affect also the small sized macro plastic fragments (2.5–5 cm). The dominant polymers were polyethylene and polypropylene while the presence of some rare polymers and waxes used in food and dentistry indicated waste water treatment plants as potential sources of microplastics.
显示更多 [+] 显示较少 [-]Scleractinian coral microplastic ingestion: Potential calcification effects, size limits, and retention 全文
2018
Hankins, Cheryl | Duffy, Allyn | Drisco, Kathryn
The impact that microplastics (<5 mm) have on scleractinian coral is largely unknown. This study investigated calcification effects, size limits, and retention times of microbeads and microfibers in two Caribbean species, Montastraea cavernosa and Orbicella faveolata, in a series of three experiments. No calcification effects were seen in the two-day exposure to a microbead concentration of 30 mg L−1. M. cavernosa and O. faveolata actively ingested microbeads ranging in size from 425 μm–2.8 mm, however, a 212–250 μm size class did not elicit a feeding response. The majority of microbeads were expelled within 48 h of ingestion. There was no difference in ingestion or retention times of 425–500 μm microbeads versus 3–5 mm long microfibers. M. cavernosa and O. faveolata have the ability to recognize and reject indigestible material, yet, there is still a need to study effects of energetics and microplastic contamination as a result of ingestion and egestion.
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