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Regional distribution of halogenated organophosphate flame retardants in seawater samples from three coastal cities in China Full text
2014
Hu, Mengyang | Li, Jun | Zhang, Beibei | Cui, Qinglan | Wei, Si | Yu, Hongxia
Thirteen samples of seawater were collected from Yellow Sea and East China Sea near Qingdao, Lianyungang, and Xiamen, China. They were analyzed for halogenated organophosphorus flame retardants (OPFRs). The compounds selected for detection were Tris(2-chloroethyl) phosphate (TCEP), Tris(2-chloroisopropyl) phosphate (TCPP), Tris (1,3-dichloro-2-propyl) phosphate (TDCPP), and Tris(2,3-dibromopropyl) phosphate (TDBPP). The total concentrations ranged from 91.87 to 1392ng/L and the mean concentrations of these four chemicals were 134.44, 84.12, 109.28, and 96.70ng/L, respectively. TCEP exhibited the highest concentrations, although concentrations of TCPP and TDCPP were also fairly high in Lianyungang and Xiamen. Generally, Lianyungang was the most heavily polluted district, with very high concentrations of TCEP at LYG-2 (550.54ng/L) and LYG-4 (617.92ng/L). The main sources of halogenated OPFRs were municipal and industrial effluents of wastewater treatment plants in the nearby economic and industrial zones.
Show more [+] Less [-]Bioconcentration of the anionic surfactant linear alkylbenzene sulfonate (LAS) in the marine shrimp Palaemonetes varians: A radiotracer study Full text
2014
Renaud, Florent | Warnau, Michel | Oberhänsli, François | Teyssié, Jean-Louis | Temara, Ali | Rouleau, Claude | Metian, Marc
Uptake and depuration kinetics of dissolved [14C]C12-6-linear alkylbenzene sulfonate (LAS) were determined in the shrimp Palaemonetes varians using environmentally relevant exposure concentration. The shrimp concentrated LAS from seawater with a mean BCF value of 120Lkg−1 after a 7-day exposure. Uptake biokinetics were best described by a saturation model, with an estimated BCFss, of 159±34Lkg−1, reached after 11.5days. Shrimp weight influenced significantly BCF value with smaller individuals presenting higher affinity to LAS. To the light of a whole body autoradiography, major accumulation of LAS occurred in the cephalothorax circulatory system (gills, heart, hepatopancreas) and ocular peduncle, but not in the flesh, limiting potential transfer to human consumers. LAS depuration rate constant value of the shrimp was 1.18±0.08d−1 leading to less than 1% of remaining LAS in its tissues after 8days of depuration.
Show more [+] Less [-]Seasonal distribution of ultraphytoplankton and heterotrophic prokaryotes in relation to abiotic variables on the north coast of Sfax after restoration Full text
2014
Rekik, Amira | Denis, Michel | Dugenne, Mathilde | Barani, Aude | Maalej, Sami | Ayadi, Habib
The Taparura project was set up to restore the north Sfax coast (Tunisia) by shutting down the northern phosphate plant responsible for chronic pollution and uncontrolled phosphogypsum dumping. The restoration effect on coastal ultraphytoplankton (<10μm) and heterotrophic prokaryotes was investigated using conventional flow cytometry over four successive seasons during 2009–2010. Cell concentrations were generally higher than values reported for the open sea, both in the western and eastern Mediterranean basins. One striking point was that chl a concentration on the north Sfax coast was unchanged after restoration but was still one order of magnitude higher than in the Gulf of Gabès. Restoration of pH, following the shutdown of the phosphate processing plants on the north coast, appeared to reach normal levels for seawater during the study, whereas seawater acidification persisted on the south coast where plants are still in operation. The largest ultraphytoplankton biomass was from an unknown cell group, whose identity and role needs to be established.
Show more [+] Less [-]Characterizing metal levels and their speciation in intertidal sediments along Mumbai coast, India Full text
2014
Fernandes, Lina L. | Nayak, G.N.
The present study investigated the concentration, distribution and speciation of metals (Fe, Mn, Cu, Pb, Co, Zn and Cr) in sediments of Mumbai region. Pearson’s correlation matrix and cluster analyses showed good association of metals with grain size and organic matter. Factor analysis applied to the speciation data helped to identify the role of different sediment fractions in metal retention. The environmental risks of metals, evaluated by sediment quality guidelines, revealed some contamination in the region. However, the Individual and Global Contamination Factors and the Risk Assessment Code, suggested low risk to the aquatic environment, except of Mn in the creek sediments.
Show more [+] Less [-]Interactive effects of hypoxia and PBDE on larval settlement of a marine benthic polychaete Full text
2014
Shin, Paul K.S. | Gopalakrishnan, Singaram | Chan, Alice K.Y. | Qian, P.Y. | Wu, Rudolf S.S.
Marine benthic polychaete Capitella sp. I is widely known to adapt to polluted habitats; however, its response to xenobiotics under hypoxic conditions has been rarely studied. This research aimed to test the hypothesis that interactive effects of hypoxia and congener BDE-47 of polybrominated diphenyl ethers (PBDE), which is ubiquitous in marine sediments, may alter the settlement of Capitella sp. I. Our results revealed that under hypoxic condition, settlement success and growth in body length of Capitella larvae were significantly reduced compared to those under normoxia of similar BDE-47 concentration. While no significant changes in morphology of settled larvae were noted in both exposure conditions, the presence of BDE-47 could enhance polychaete growth. The present findings demonstrated that the interactive effects of hypoxia and environmentally realistic concentrations of BDE-47 in sediments could affect polychaete settlement, which, in turn, reduce its recruitment and subsequent population size in the marine benthic ecosystem.
Show more [+] Less [-]Review of oil spill remote sensing Full text
2014
Fingas, Mervin F. | Brown, Carl
Remote-sensing for oil spills is reviewed. The use of visible techniques is ubiquitous, however it gives only the same results as visual monitoring. Oil has no particular spectral features that would allow for identification among the many possible background interferences. Cameras are only useful to provide documentation. In daytime oil absorbs light and remits this as thermal energy at temperatures 3–8K above ambient, this is detectable by infrared (IR) cameras.Laser fluorosensors are useful instruments because of their unique capability to identify oil on backgrounds that include water, soil, weeds, ice and snow. They are the only sensor that can positively discriminate oil on most backgrounds. Radar detects oil on water by the fact that oil will dampen water-surface capillary waves under low to moderate wave/wind conditions. Radar offers the only potential for large area searches, day/night and foul weather remote sensing.
Show more [+] Less [-]Distribution, sources and potential toxicological significance of polycyclic aromatic hydrocarbons (PAHs) in surface soils of the Yellow River Delta, China Full text
2014
Yuan, Hongming | Li, Tiegang | Ding, Xigui | Zhao, Guangming | Ye, Siyuan
PAH concentrations of 61 surface soil samples collected from the Yellow River Delta (YRD), China were measured to determine occurrence levels, sources, and potential toxicological significance of PAHs. The total concentrations of ∑PAHs ranged from 27 to 753ng/g d.w., with a mean of 118±132ng/g. The highest concentrations was found in the mid-southern part of the YRD (753ng/g), which was associated with the oil exploration. The ratios indicated that the PAHs throughout the YRD were mostly of pyrogenic origin; while various sites in mid-southern part in the region were derived mainly from the petrogenic sources. Multivariate statistical analyses supported that the PAHs in surface soils of the YRD were principally from the coal and biomass combustion, petroleum spills, and/or vehicular emissions. The toxic assessment suggested that the PAHs in soils were at low potential of ecotoxicological contamination level for the YRD.
Show more [+] Less [-]High-levels of microplastic pollution in a large, remote, mountain lake Full text
2014
Free, Christopher M. | Jensen, Olaf P. | Mason, Sherri A. | Eriksen, Marcus | Williamson, Nicholas J. | Boldgiv, Bazartseren
Despite the large and growing literature on microplastics in the ocean, little information exists on microplastics in freshwater systems. This study is the first to evaluate the abundance, distribution, and composition of pelagic microplastic pollution in a large, remote, mountain lake. We quantified pelagic microplastics and shoreline anthropogenic debris in Lake Hovsgol, Mongolia. With an average microplastic density of 20,264 particles km−2, Lake Hovsgol is more heavily polluted with microplastics than the more developed Lakes Huron and Superior in the Laurentian Great Lakes. Fragments and films were the most abundant microplastic types; no plastic microbeads and few pellets were observed. Household plastics dominated the shoreline debris and were comprised largely of plastic bottles, fishing gear, and bags. Microplastic density decreased with distance from the southwestern shore, the most populated and accessible section of the park, and was distributed by the prevailing winds. These results demonstrate that without proper waste management, low-density populations can heavily pollute freshwater systems with consumer plastics.
Show more [+] Less [-]Developmental toxicity of PAH mixtures in fish early life stages. Part I: adverse effects in rainbow trout Full text
2014
Le Bihanic, Florane | Morin, Bénédicte | Cousin, Xavier | Le Menach, Karyn | Budzinski, Hélène | Cachot, Jérôme | Université Sciences et Technologies - Bordeaux 1 (UB) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Physiologie et Génomique des Poissons (LPGP) ; Institut National de la Recherche Agronomique (INRA)-Structure Fédérative de Recherche en Biologie et Santé de Rennes (Biosit : Biologie - Santé - Innovation Technologique) | Unité Biogéochimie et Ecotoxicologie (BE) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | ANR ConPhyPop (2009-002) ; CPER A2E ; European Regional Development Fund ; GDR EXECO ; Aquitaine Region ; Ministère de l'Enseignement Supérieur et de la Recherche
Developmental toxicity of PAH mixtures in fish early life stages. Part I: adverse effects in rainbow trout Full text
2014
Le Bihanic, Florane | Morin, Bénédicte | Cousin, Xavier | Le Menach, Karyn | Budzinski, Hélène | Cachot, Jérôme | Université Sciences et Technologies - Bordeaux 1 (UB) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Physiologie et Génomique des Poissons (LPGP) ; Institut National de la Recherche Agronomique (INRA)-Structure Fédérative de Recherche en Biologie et Santé de Rennes (Biosit : Biologie - Santé - Innovation Technologique) | Unité Biogéochimie et Ecotoxicologie (BE) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | ANR ConPhyPop (2009-002) ; CPER A2E ; European Regional Development Fund ; GDR EXECO ; Aquitaine Region ; Ministère de l'Enseignement Supérieur et de la Recherche
A new gravel-contact assay using rainbow trout, Oncorhynchus mykiss, embryos was developed to assess the toxicity of polycyclic aromatic hydrocarbons (PAHs) and other hydrophobic compounds. Environmentally realistic exposure conditions were mimicked with a direct exposure of eyed rainbow trout embryos incubated onto chemical-spiked gravels until hatching at 10 °C. Several endpoints were recorded including survival, hatching delay, hatching success, biometry, developmental abnormalities, and DNA damage (comet and micronucleus assays). This bioassay was firstly tested with two model PAHs, fluoranthene and benzo[a]pyrene. Then, the method was applied to compare the toxicity of three PAH complex mixtures characterized by different PAH compositions: a pyrolytic extract from a PAH-contaminated sediment (Seine estuary, France) and two petrogenic extracts from Arabian Light and Erika oils, at two environmental concentrations, 3 and 10 μg g−1 sum of PAHs. The degree and spectrum of toxicity were different according to the extract considered. Acute effects including embryo mortality and decreased hatching success were observed only for Erika oil extract. Arabian Light and pyrolytic extracts induced mainly sublethal effects including reduced larvae size and hemorrhages. Arabian Light and Erika extracts both induced repairable DNA damage as revealed by the comet assay versus the micronucleus assay. The concentration and proportion of methylphenanthrenes and methylanthracenes appeared to drive the toxicity of the three PAH fractions tested, featuring a toxic gradient as follows: pyrolytic < Arabian Light < Erika. The minimal concentration causing developmental defects was as low as 0.7 μg g−1 sum of PAHs, indicating the high sensitivity of the assay and validating its use for toxicity assessment of particle-bound pollutants.
Show more [+] Less [-]Developmental toxicity of PAH mixtures in fish early life stages. Part I: adverse effects in rainbow trout Full text
2014
Le Bihanic, Florane | Morin, Benedicte | Cousin, Xavier | Le Menach, Karyn | Budzinski, Helene | Cachot, Jerome
A new gravel-contact assay using rainbow trout, Oncorhynchus mykiss, embryos was developed to assess the toxicity of polycyclic aromatic hydrocarbons (PAHs) and other hydrophobic compounds. Environmentally realistic exposure conditions were mimicked with a direct exposure of eyed rainbow trout embryos incubated onto chemical-spiked gravels until hatching at 10 °C. Several endpoints were recorded including survival, hatching delay, hatching success, biometry, developmental abnormalities, and DNA damage (comet and micronucleus assays). This bioassay was firstly tested with two model PAHs, fluoranthene and benzo[a]pyrene. Then, the method was applied to compare the toxicity of three PAH complex mixtures characterized by different PAH compositions: a pyrolytic extract from a PAH-contaminated sediment (Seine estuary, France) and two petrogenic extracts from Arabian Light and Erika oils, at two environmental concentrations, 3 and 10 μg g−1 sum of PAHs. The degree and spectrum of toxicity were different according to the extract considered. Acute effects including embryo mortality and decreased hatching success were observed only for Erika oil extract. Arabian Light and pyrolytic extracts induced mainly sublethal effects including reduced larvae size and hemorrhages. Arabian Light and Erika extracts both induced repairable DNA damage as revealed by the comet assay versus the micronucleus assay. The concentration and proportion of methylphenanthrenes and methylanthracenes appeared to drive the toxicity of the three PAH fractions tested, featuring a toxic gradient as follows: pyrolytic < Arabian Light < Erika. The minimal concentration causing developmental defects was as low as 0.7 μg g−1 sum of PAHs, indicating the high sensitivity of the assay and validating its use for toxicity assessment of particle-bound pollutants.
Show more [+] Less [-]An approach to detecting species diversity of microfaunas in colonization surveys for marine bioassessment based on rarefaction curves Full text
2014
Xu, Guangjian | Zhong, Xiaoxiao | Wang, Yangfan | Xu, Henglong
The objective of this study was to measure α-, β- and γ-diversity of microfaunas with different ages in colonization surveys using rarefaction-modeling methods. A dataset was complied based on a microperiphyton survey in coastal waters of the Yellow Sea, near Qingdao. The analyses showed that: (1) there was a strong residual influence of sampling effort on β- and γ-diversity after rarefaction, especially for the young communities; (2) the rarefaction curves were well fitted to the Michaelis–Menten equation, and allow modeling and removing the residual influence of sampling effort on β- and γ-diversity; and (3) the estimated values of α-, β- and γ-diversity of a community based on the rarefaction-modeling method were independent of the influence of sampling effort. The results suggest that this approach may be used as a feasible tool to detect α-, β- and γ-diversity without the influence of sampling effort in microfauna colonization surveys for marine bioassessment.
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