Refine search
Results 551-560 of 1,310
Organochlorine pesticides in sediments of Laizhou Bay and its adjacent rivers, North China Full text
2011
Zhong, Guangcai | Tang, Jianhui | Zhao, Zhen | Pan, Xiaohui | Chen, Yingjun | Li, Jun | Zhang, Gan
Organochlorine pesticides (HCHs, DDTs and HCB) have been investigated in sediments of Laizhou Bay and its adjacent rivers. The average concentrations of HCHs, DDTs and HCBs are 0.09ng/gdw, 0.59 and 0.05 for marine sediments and 0.55, 8.6 and 1.1 for riverine sediments, respectively. Laizhou Bay is less contaminated by HCHs and DDTs in comparison with other coastal regions around the world, including the other two biggest bays in Bohai Sea. Fresh input of lindane and dicofol-type DDT were found in several riverine sites. Relatively strong TOC-dependence of HCB distribution in the entire studied area suggested no point source existed and/or water–sediment equilibrium achieved. No significant difference of α/γ-HCH ratios have been observed between marine and riverine sediments. However, o,p′-DDT/p,p′-DDT ratios varied largely between the two regions.
Show more [+] Less [-]Testes specific accumulation of tributyltin in turbot Scophthalmus maximus from the southern Baltic Sea Full text
2011
Gosz, E. | Horbowy, J. | Ruczyńska, W.
Concentrations of tributyltin (TBT) and its breakdown products, dibutyltin (DBT) and monobutyltin (MTB), were measured in tissues of male turbot Scophthalmus maximus from the Gulf of Gdańsk (GDA) and the Pomeranian Bay (POM) in the southern Baltic Sea. The fish (n=206) were collected during the spawning seasons of 2008–2009. All specimens were at the same maturity stage and in full breeding condition. The ripe testes of the turbot appeared to be a target tissue for TBT accumulation. We report that TBT is extensively eliminated at the specific whole-body level and that the males from TBT-contaminated location (GDA) reach this specific level at 23–24cm in total length.
Show more [+] Less [-]PBDEs in the blubber of marine mammals from coastal areas of São Paulo, Brazil, southwestern Atlantic Full text
2011
Yogui, G.T. | Santos, M.C.O. | Bertozzi, C.P. | Sericano, J.L. | Montone, R.C.
Limited information is available in the literature on the levels of brominated flame retardants in the southern hemisphere. This study presents concentrations of polybrominated diphenyl ethers (PBDEs) in the blubber of small cetaceans from the coast of São Paulo (Brazil), southwestern Atlantic. PBDE levels were highest in Stenellafrontalis (770ngg⁻¹ lipid) followed by Stenobredanensis (475ngg⁻¹ lipid), Sotaliaguianensis (65.6ngg⁻¹ lipid), Tursiopstruncatus (64.2ngg⁻¹ lipid) and Pontoporiablainvillei (60.3ngg⁻¹ lipid). In general, continental shelf individuals exhibited higher contamination than inshore animals. This might be related to larger prey items consumed by continental shelf dolphins. The pattern of contamination indicates that Penta-BDE commercial mixtures are a major source of PBDEs to top predators in the southwestern Atlantic. Congeners found in Octa-BDE formulations were not detected in the investigated animals.
Show more [+] Less [-]Occurrence and distribution of hydrocarbons in the surface microlayer and subsurface water from the urban coastal marine area off Marseilles, Northwestern Mediterranean Sea Full text
2011
Guigue, Catherine | Tedetti, Marc | Giorgi, Sébastien | Goutx, Madeleine
Aliphatic (AHs) and polycyclic aromatic hydrocarbons (PAHs) were analyzed in dissolved and particulate material from surface microlayer (SML) and subsurface water (SSW) sampled at nearshore observation stations, sewage effluents and harbour sites from Marseilles coastal area (Northwestern Mediterranean) in 2009 and 2010. Dissolved and particulate AH concentrations ranged 0.05–0.41 and 0.04–4.3μgl⁻¹ in the SSW, peaking up to 38 and 1366μgl⁻¹ in the SML, respectively. Dissolved and particulate PAHs ranged 1.9–98 and 1.9–21ngl⁻¹ in the SSW, amounting up 217 and 1597ngl⁻¹ in the SML, respectively. In harbours, hydrocarbons were concentrated in the SML, with enrichment factors reaching 1138 for particulate AHs. Besides episodic dominance of biogenic and pyrogenic inputs, a moderate anthropisation from petrogenic sources dominated suggesting the impact of shipping traffic and surface runoffs on this urbanised area. Rainfalls increased hydrocarbon concentrations by a factor 1.9–11.5 in the dissolved phase.
Show more [+] Less [-]Differential concentration of Technetium-99 (⁹⁹Tc) in common intertidal molluscs with different food habits Full text
2011
Sjøtun, K. | Heldal, H.E. | Brakstad, D.S.
Concentration of ⁹⁹Tc has been measured in fucoids and molluscs, sampled in a sheltered intertidal at the southwest coast of Norway from February to November 2006. The concentrations of ⁹⁹Tc in molluscs differed significantly between species. The filtering bivalve Mytilus edulis had the lowest concentrations with averages of 2.3–5.9Bqkg⁻¹d.w., while the herbivorous gastropods Littorinalittorina, Littorina obtusata and Patella vulgata had higher concentrations. P. vulgata and L. obtusata had the highest concentrations, 40–47 and 26–30Bqkg⁻¹d.w., respectively. L. obtusata has a specialized habit of living, and prefers to feed on fucoids. P. vulgata can graze extensively on the fucoid Ascophyllum nodosum when available. Fucoids are known to have very high uptake of ⁹⁹Tc, and this was also found in the present study. The high ⁹⁹Tc-concentrations of L. obtusata and P. vulgata are most likely due to their habit of feeding on fucoids.
Show more [+] Less [-]Evaluation of physical, chemical and microbiological parameters of water quality in the Harris Neck estuarine marshes along the Georgia coast Full text
2011
Markand, Shanu | Bachoon, Dave S. | Gentit, Lisa | Sherchan, Samendra | Gates, Keith
Analysis of the physical, chemical and biological parameters assessing water quality in Harris Neck estuary indicated that the average dissolved oxygen level was 8.6mg/L, it maintained moderate levels of total dissolved nitrogen (2.7–4.6mg/L) and total dissolved phosphorous (<0.05mg/L), chlorophyll a was above 5.0μg/L and it is contaminated with low levels of fecal bacteria. Bifidobacterium adolescentis, a putative marker of human fecal pollution, was detected once at stations 3 and 5. Overall the Harris Neck water quality analyses indicated a relatively pristine and a healthy functioning marine environment.
Show more [+] Less [-]Bioaccumulation of nitroarenes in bivalves at Osaka Bay, Japan Full text
2011
Uno, Seiichi | Tanaka, Hiroyuki | Miki, Shizuho | Kokushi, Emiko | Ito, Kazuki | Yamamoto, Masataka | Koyama, Jiro
This paper reports for the first time the detection and occurrence of nitroarenes (NPAHs) in marine organisms. Mussels and oysters collected from Osaka Bay, Japan, had total NPAHs concentrations that ranged from 2380 to 24,688pg/g dry and 2672 to 25,961pg/g dry, respectively. Relatively higher concentrations were detected in sampling sites located near the central district and suburbs of Osaka City implying that the most probable sources of NPAHs in the two bivalves are exhaust gases and smokes emitted by automobiles and industrial plants. Bivalves had relatively higher residues of 1-nitronaphthalene, 2-nitronaphthalene, 3-nitrophenanthrene, and 9-nitrophenanthrenes. Residues of 2-nitrofluorene, 1-nitropyrene, 4-nitropyrenes, and 6-nitrochrysene were much lower compared to nitronaphthalenes and nitrophenanthrenes. Inter-species differences was only observed for 2-nitronaphthalene with oysters exhibiting significantly higher residues than mussels.
Show more [+] Less [-]Environmental toxicology: Population modeling of cod larvae shows high sensitivity to loss of zooplankton prey Full text
2011
Stige, Leif Christian | Ottersen, Geir | Hjermann, Dag Ø | Dalpadado, Padmini | Jensen, Louise K. | Stenseth, Nils Chr
Two factors determine whether pollution is likely to affect a population indirectly through loss of prey: firstly, the sensitivity of the prey to the pollutants, and secondly, the sensitivity of the predator population to loss of prey at the given life stage. We here apply a statistical recruitment model for Northeast Arctic cod to evaluate the sensitivity of cod cohorts to loss of zooplankton prey, for example following an oil spill. The calculations show that cod cohorts are highly sensitive to possible zooplankton biomass reductions in the distribution area of the cod larvae, and point to a need for more knowledge about oil-effects on zooplankton. Our study illustrates how knowledge about population dynamics may guide which indirect effects to consider in environmental impact studies.
Show more [+] Less [-]Evaluation of heavy metals and arsenic speciation discharged by the industrial activity on the Tinto-Odiel estuary, SW Spain Full text
2011
Pérez López, Rafael | Nieto, José Miguel | López-Cascajosa, M José | Díaz-Blanco, M Jesús | Sarmiento, Aguasanta M. | Oliveira, Vanesa | Sánchez-Rodas, Daniel
This study reports the annual amount of heavy metals discharged by industrial activity into the estuary of the Ría of Huelva (SW Spain). The findings showed that the discharged metals found in highest amounts were Fe (11ty⁻¹), Zn (3.4ty⁻¹) and Mo (0.88ty⁻¹). There were other metals with high pollutant charge, such as Ti (232kgy⁻¹), As (228kgy⁻¹), Ni (195kgy⁻¹), Pb (100kgy⁻¹), Cr (39kgy⁻¹) and Cd (33kgy⁻¹). These results were compared with pollutants transported via the Tinto and Odiel rivers from abandoned mining activities in the Iberian Pyrite Belt (IPB), and it was deduced that the amounts spilled exclusively by industries were less than 1% in relation to the total discharge. Hence, the treatment of residues from the IPB should be the priority goal to improve water quality in the estuary.
Show more [+] Less [-]The occurrence of chemical elements and POPs in loggerhead turtles (Caretta caretta): An overview Full text
2011
D’Ilio, S. | Mattei, D. | Blasi, M.F. | Alimonti, A. | Bogialli, S.
Chemical elements and persistent organic pollutants (POPs) are globally present in aquatic systems and their potential transfer to loggerhead marine turtles (Caretta caretta) has become a serious threat for their health status. The environmental fate of these xenobiotics may be traced by the analysis of turtles’ tissues and blood. Generally, loggerhead turtles exhibited a higher metal load than other turtle species, this could be explained by differences in diet habits being food the main source of exposure. Literature shows that muscle, liver and kidney are most considered for the quantification of chemical elements, while, organic compounds are typically investigated in liver and fat. This paper is an overview of the international studies carried out on the quantification of chemical elements, polychlorinated biphenyls (PCBs), organochlorines (OCs) and perfluorinated compounds (PFCs), in tissues, organs and fluids of C. caretta from the Mediterranean Sea, the Atlantic and the Pacific Oceans.
Show more [+] Less [-]