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Absence of selenium protection against methylmercury toxicity in harbour seal leucocytes in vitro
2016
Dāsa, Kr̥shṇā | Dupont, Aurélie | De Pauw-Gillet, Marie- Claire | Debier, Cathy | Siebert, Ursula
Previous studies described high concentrations of mercury (Hg) and selenium (Se) in the blood of harbour seals, Phoca vitulina from the North Sea. In the present study, we evaluated the in vitro potential protective effects of sodium selenite (Na2SeO3) and selenomethionine (SeMet) on cell proliferation of harbour seal lymphocytes exposed to MeHgCl 0.75μM. In vitro exposure of ConA-stimulated T lymphocytes resulted in severe inhibition of DNA synthesis, likely linked to severe loss of mitochondrial membrane potential at 0.75μM. Neither selenite nor SeMet showed a protective effect against MeHg toxicity expressed at the T lymphocyte proliferation level for harbour seals. Selenite and SeMet did not show negative effects regarding lymphocyte proliferation and mitochondrial membrane potential.To conclude, our results clearly demonstrated that MeHg affected in vitro immune cells exposure with no protective effects of selenium at a molar ratio Hg:Se of 1:10 in harbour seals from the North Sea.
Mostrar más [+] Menos [-]Active biomonitoring of mussels Mytilus galloprovincialis with integrated use of micronucleus assay and physiological indices to assess harbor pollution
2016
Gherras Touahri, Hamida | Boutiba, Zitouni | Benguedda, Wacila | Shaposhnikov, Sergey
The mussels Mytilus galloprovincialis collected from a noncontaminated site (Chaib Rasso) were transplanted during one, three and six months at Ghazaouet harbor (GH), areas with a strong gradient of pollution. The micronucleus test (MN) was selected to monitor the impact of contamination, along with physiological indexes (condition index CI and organo-somatic indexes RI and GSI). The results show a negative correlation of MN variation in gill cells with CI but a positive correlation with transplantation duration. However, a significant correlation was found between the indexes. Moreover, the findings indicate that MN in the hemolymph and gills of transplanted mussels for one, three and six months at GH are significantly higher than those of the reference site. However, no significant differences were noted between the three transplants at the two organs. Monitoring the physiological status of mussels, in parallel with the biomarker measurements, is useful in assessing the impact of contaminants.
Mostrar más [+] Menos [-]Spatio-temporal distributions of chlorofluorocarbons and methyl iodide in the Changjiang (Yangtze River) estuary and its adjacent marine area
2016
Yuan, Da | Yang, Gui-Peng | He, Zhen
Temporal and spatial distribution patterns of volatile halogenated organic compounds (VHOCs), such as dichlorodifluoromethane (CFC-12), trichlorofluoromethane (CFC-11), trichlorotrifluoroethane (CFC-113), and methyl iodide (CH3I), in the Changjiang (Yangtze River) estuary and its adjacent marine area were measured during two cruises from 21 February to 10 March 2014 and from 10 to 21 July 2014. VHOC concentrations showed seasonal variation with higher values during winter. VHOC distributions evidently decreased along the freshwater plume from the river mouth to the open sea and from inshore to offshore regions. VHOC distributions were obviously influenced by the Changjiang runoff, anthropogenic inputs, and biological release of phytoplankton. The study area was a net sink for CFC-12 and CFC-11, but a net source for atmospheric CH3I during the study periods.
Mostrar más [+] Menos [-]Islands in the oil: Quantifying salt marsh shoreline erosion after the Deepwater Horizon oiling
2016
Turner, R Eugene | McClenachan, Giovanna | Tweel, Andrew W.
Qualitative inferences and sparse bay-wide measurements suggest that shoreline erosion increased after the 2010 BP Deepwater Horizon (DWH) disaster, but quantifying the impacts has been elusive at the landscape scale. We quantified the shoreline erosion of 46 islands for before and after the DWH oil spill to determine how much shoreline was lost, if the losses were temporary, and if recovery/restoration occurred. The erosion rates at the oiled islands increased to 275% in the first six months after the oiling, were 200% of that of the unoiled islands for the first 2.5years after the oiling, and twelve times the average land loss in the deltaic plain of 0.4%y−1 from 1988 to 2011. These results support the hypothesis that oiling compromised the belowground biomass of the emergent vegetation. The islands are, in effect, sentinels of marsh stability already in decline before the oil spill.
Mostrar más [+] Menos [-]Nutrient distribution and structure affect the acidification of eutrophic ocean margins: A case study in southwestern coast of the Laizhou Bay, China
2016
Zhang, Jinfeng | Gao, Xuelu
The effects of nutrient distribution and structure on the acidity of coastal waters were analyzed based on the data of 48 surface water samples collected in the southwestern coast of the Laizhou Bay and its adjacent rivers (SWLZB) which are heavily influenced by nutrient-laden discharges. The concentration and structure of nutrients varied considerably along the coast owing to different contributors. The studied inshore waters exhibited a sign of acidification. The pH was significantly negatively correlated with the concentration of NO3-N, NO2-N, NH4-N and DSi, but showed no obvious correlation with the concentration of PO4-P and the ratio of TDN/TDP, DSi/DIN and DSi/PO4-P, respectively. The results indicated that the distribution of nutrients might well be an important environmental factor affecting the acidification of the SWLZB in warmer months.
Mostrar más [+] Menos [-]Microbiome analysis and detection of pathogenic bacteria of Penaeus monodon from Jakarta Bay and Bali
2016
Oetama, Vincensius S.P. | Hennersdorf, Philipp | Abdul-Aziz, Muslihudeen A. | Mrotzek, Grit | Haryanti, Haryanti | Saluz, Hans Peter
Penaeus monodon, the Asian black tiger shrimp is one of the most widely consumed marine crustaceans worldwide. In this study, we examine and compare the fecal microbiota of P. monodon from highly polluted waters around Jakarta Bay, with those of less polluted waters of Bali. Using next generation sequencing techniques, we identified potential bacterial pathogens and common viral diseases of shrimp. Proteobacteria (96.08%) was found to be the most predominant phylum, followed by Bacteriodetes (2.32%), Fusobacteria (0.96%), and Firmicutes (0.53%). On the order level, Vibrionales (66.20%) and Pseudoaltermonadales (24.81%) were detected as predominant taxa. qPCR profiling was used as a confirmatory step and further revealed Vibrio alginolyticus and Photobacterium damselae as two potential pathogenic species present in most of the samples. In addition, viral diseases for shrimp were discovered among the samples, WSSV in Jakarta free-living samples, YHV in Bali free-living samples and IHHNV in both.
Mostrar más [+] Menos [-]Is there a direct relationship between stress biomarkers in oysters and the amount of metals in the sediments where they inhabit?
2016
Rodriguez-Iruretagoiena, A. | Rementeria, A. | Zaldibar, B. | de Vallejuelo, S Fdez-Ortiz | Gredilla, A. | Arana, G. | de Diego, A.
The effects exerted by metals in oysters are still a matter of debate and require more detailed studies. In this work we have investigated whether the health status of oysters are affected by the amount of metals present in the sediments of their habitat. Sediments and oysters were collected in the tidal part of the estuary of the Oka River (Basque Country), representative of other mesotidal, well mixed and short estuaries of the European Atlantic coast. The concentrations of 14 elements were determined in all the samples. Several biomarkers were also measured in the soft tissues of oysters. According to the concentrations found, the sediments were classified as non-toxic or slightly toxic. In good agreement, the histological alterations observed in oysters were not severe. Interestingly, in those sampling sites where the sediments showed relatively high metal concentrations, the metallic content in oysters was lower, and vice versa.
Mostrar más [+] Menos [-]Trace metals in the surface sediments of the intertidal Jiaozhou Bay, China: Sources and contamination assessment
2016
Xu, Fangjian | Qiu, Longwei | Cao, Yingchang | Huang, Jingli | Liu, Zhaoqing | Tian, Xu | Li, Anchun | Yin, Xuebo
The major (Al) and trace metal (Cu, Pb, Zn, Cr, Cd, and As) concentrations in 29 surface sediment samples from the intertidal Jiaozhou Bay (JZB) are evaluated to assess the contamination level. The results show that the overall sediment quality in the area has been obviously impacted by trace metal contamination. The geoaccumulation index and the enrichment factor values indicate that no Cr or Cu contamination has occurred on the whole, only a few stations have been polluted by As, and some areas have been polluted by Cd, Pb, and Zn. Principal component analysis suggests that the Cu, Pb, Zn, and Cd are derived from anthropogenic inputs and that Cr, As, Cu, and Zn are influenced by natural weathering processes. Cu and Zn may originate from both natural and anthropogenic sources. The contamination in the northeastern JZB is higher than that in other areas of the bay.
Mostrar más [+] Menos [-]Excitation–emission matrix scan analysis of raw fish oil from coastal New Jersey menhaden collected before and after Hurricane Sandy
2016
Bentivegna, Carolyn S. | DeFelice, Chelsea R. | Murphy, Wyatt R.
The impact of Hurricane Sandy (October 29, 2012) on PAH exposure was investigated in adult Atlantic menhaden (Brevoortia tyrannus) collected along the NJ coast. Collections were made in August, September and/or October of 2011, 2012 and 2013. PAHs were monitored in raw fish oil using excitation–emission matrix (EEM) spectroscopy. Results showed that raw fish oils had relatively high levels of high molecular weight, PAH-like compounds (173 to 24,421ng/mL) compared to values reported for bile in other species. EEM profiles resembled that of crude oil and excluded matrix interference by some common biological molecules that also fluoresce. Concentrations and EEM profiles varied by collection; however, collection ship, month, year and fish size did not account for the data. Replicates showed that fish from the same catch had similar PAH exposure. Overall, Hurricane Sandy did not alter body burdens of PAHs in raw fish oil of menhaden.
Mostrar más [+] Menos [-]Indoor air quality investigation of the school environment and estimated health risks: Two-season measurements in primary schools in Kozani, Greece
2016
Kalimeri, Krystallia K. | Saraga, Dikaia E. | Lazaridis, Vasileios D. | Legkas, Nikolaos A. | Missia, Dafni A. | Tolis, Evangelos I. | Bartzis, John G.
Two primary schools and one kindergarten were selected in the city of Kozani, Greece in order to investigate the school environment, the indoor air pollutants that children are exposed to and possible health risks at school. In each school three classrooms and one outdoor position were monitored from Monday to Friday, in both non-heating (26/09/2011–14/10/2011) and heating (23/01/2012–10/02/2012) period. Temperature, relative humidity and CO2, were continuously monitored. Formaldehyde, benzene, trichloroethylene, pinene, limonene, NO2 and O3 were measured with diffusive samplers. CO was monitored every day (30 min/day). Radon was measured for four weeks with short term radon detectors. PM2.5 was gravimetrically determined while PM2.5 and PM10 fractions were measured using the optical light scattering technique. Building material emission testing for VOCs was performed using the Field and Laboratory Emission Cell (FLEC). The ventilation rate for each classroom was calculated based on the CO2 measurements.Results indicated that indoor air concentrations of the measured pollutants were within accepted limits with indicative ranges 1.5–9.4 μg/m3 for benzene, 2.3–28.5 μg/m3 for formaldehyde, 4.6–43 μg/m3 for NO2 and 0.1–15.6 μg/m3 for O3. Emissions from building materials seem to have a significant contribution to the indoor air quality. Very low ventilation rates (0.1–3.7 L/s per person) were observed, indicating inadequate ventilation and possible indoor air quality problems requiring intervention measures. The estimated average lifetime cancer risks for benzene, formaldehyde and trichloroethylene were very low.
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