1,720,988 research outputs found
Bioaccumulation of endocrine disrupting compounds in the Greenland shark Somniosus microcephalus from the Greenland seawaters.
No full textRecent climate changes associated with anthropogenic emissions of pollutants are triggering shifts in global biogeochemical cycles and polar marine ecosystem. The decrease of sea ice and the mechanism of ice formation/melting, may considerably have an impact on the mobility of contaminants and on the loss of biodiversity. In this work, we report the occurrence and bioaccumulation of selected endocrine-disrupting compounds (EDCs) in muscle and liver of the Greenland shark Somniosus microcephalus, an arctic species of interest for biogeography, migration, physiology, long- and short-term contaminant storage. The EDCs selected for this study were 4-nonylphenol (4-NP), its mono- (NP1EO) and di-ethoxylate (NP2EO) precursors and bisphenol A (BPA). There are currently very few scientific papers on the distribution and transport of these EDCs in the arctic marine food web and no such studies have been performed on the Greenland shark. Totally, muscles and liver samples were analyzed from 23 Greenland sharks (TL range 149–442 cm) sampled in W, SW, SE, and NE Greenland. Extraction of analytes from biological matrices were performed by ASE (Accelerated Solvent Extraction), followed by HPLC-Fluorescence (FLD) detection. Results showed higher contamination levels in muscle than in liver in the sharks from SE and NE Greenland, while in specimens from W and SW Greenland the liver was the tissue more contaminated. In fact, the 4-NP, NP1-2EO and BPA mean content in liver of SW Greenland specimens was 43.5 ng/g, 288.5 ng/g and 8.2 ng/g wet wt respectively, while in muscle mean concentrations was 20.3 ng/g for 4-NP, 171.1 ng/g wet wt for NP1-2EO and 7.9 ng/g for BPA. Results confirm the presence of selected EDCs in this species, suggesting the transfer of contamination in the Euro-Arctic marine trophic web
Bioaccumulation of nonylphenols and bisphenol A in the Greenland shark Somniosus microcephalus from the Greenland seawaters
No full textRecent climate changes associated with anthropogenic emissions of pollutants are triggering shifts in global biogeochemical cycles and polar marine ecosystem. The decrease of sea ice and the mechanism of ice formation/melting, may considerably have an impact on the mobility of contaminants and on the loss of biodiversity. In this work, we report the occurrence and bioaccumulation of selected endocrine-disrupting compounds (EDCs) in muscle and liver of the Greenland shark . Somniosus microcephalus, an arctic species of interest for biogeography, migration, physiology, long- and short-term contaminant storage. The EDCs selected for this study were 4-nonylphenol (4-NP), its mono- (NP1EO) and di-ethoxylate (NP2EO) precursors and bisphenol A (BPA). There are currently very few scientific papers on the distribution and transport of these EDC. s in the arctic marine food web and no such studies have been performed on the Greenland shark. Totally, muscles and liver samples were analyzed from 23 Greenland sharks (TL range 149-442. cm) sampled in W, SW, SE, and NE Greenland. Extraction of analytes from biological matrices were performed by ASE (Accelerated Solvent Extraction), followed by HPLC-Fluorescence (FLD) detection. Results showed higher contamination levels in muscle than in liver in the sharks from SE and NE Greenland, while in specimens from W and SW Greenland the liver was the tissue more contaminated. In fact, the 4-NP, NP1-2EO and BPA mean content in liver of SW Greenland specimens was 43.5. ng/g, 288.5. ng/g and 8.2. ng/g wet wt respectively, while in muscle mean concentrations was 20.3. ng/g for 4-NP, 171.1. ng/g wet wt for NP1-2EO and 7.9. ng/g for BPA. Results confirm the presence of selected EDCs in this species, suggesting the transfer of contamination in the Euro-Arctic marine trophic web
Determination of nonionic aliphatic and aromatic polyethoxylated surfactants in environmental aqueous samples
No full textNonionic surfactants of the polyethoxylate type are environmentally relevant because of their ubiquitous presence in raw and treated, municipal and industrial, wastewaters. Until today the
standard methods currently used for the routine determination of nonionic surfactants in environmental matrices are cumulative methods (BIAS, CTAS, PPAS, TAS), which are poorly reliable,
particularly in terms of accuracy, and do not supply any structural information on the ethoxymeric and homolog composition, as well as on the chain length of the hydrophobic moiety. This paper
describes a specific analytical procedure for the simultaneous specific determination of polyethoxylate aliphatic (AE) and aromatic (APE) nonionics in aqueous matrices. The analytes were
isolated from water samples by solid phase extraction with graphitized carbon black and then derivatized with 1-naphthylisocyanate (NIC). AE and APE were separated by reversed-phase
HPLC combined with fluorescence detection (RP-HLPC/FL). The analytical procedure was applied to the monitoring of these two classes of surfactants in a municipal sewage treatment plant.
The method allows rapid, precise and reliable determination of AE and APE in environmental samples at concentrations as low as 0.1 g/L
Germination, root elongation, and photosynthetic performance of plants exposed to sodium lauryl ether sulfate (SLES): an emerging contaminant
No full textThe anionic surfactant SLES (sodium lauryl ether sulfate) is an emerging contaminant, being the main component of foaming agents that are increasingly used by the tunnel construction industry. To fill the gap of knowledge about the potential SLES toxicity on plants, acute and chronic effects were assessed under controlled conditions. The acute ecotoxicological test was performed on Lepidum sativum L. (cress) and Zea mays L. (maize). Germination of both species was not affected by SLES in soil, even at concentrations (1200 mg kg−1) more than twice higher than the maximum realistic values found in contaminated debris, thus confirming the low acute SLES toxicity on terrestrial plants. The root elongation of the more sensitive species (cress) was instead reduced at the highest SLES concentration. In the chronic phytotoxicity experiment, photosynthesis of maize was downregulated, and the photosynthetic performance (PITOT) significantly reduced already under realistic exposures (360 mg kg−1), owing to the SLES ability to interfere with water and/or nutrients uptake by roots. However, such reduction was transient, likely due to the rapid biodegradation of the surfactant by the soil microbial community. Indeed, SLES amount decreased in soil more than 90% of the initial concentration in only 11 days. A significant reduction of the maximum photosynthetic capacity (Pnmax) was still evident at the end of the experiment, suggesting the persistence of negative SLES effects on plant growth and productivity. Overall results, although confirming the low phytotoxicity and high biodegradability of SLES in natural soils, highlight the importance of considering both acute and nonlethal stress effects to evaluate the environmental compatibility of soil containing SLES residues
Multiple exposure of the Boreogadus saida populations to legacy and emerging pollutants from inner and outer Bessel fjord (NE Greenland)
No full textTemporal trend of perfluoroalkyl substances and current-use pesticides in penguin eggs from the Ross Sea (Antarctica)
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Multiple exposure of the Boreogadus saida from Bessel fjord (NE Greenland) to legacy and emerging pollutants
No full textThis work investigates the occurrence of OCPs, such as hexachlorocyclohexane (α-, β-, γ- and δ-HCH) isomers, dichlorodiphenyltrichloroethane (p,p’-DDT) and its metabolite dichlorodiphenyldichloroethylene (p,p’-DDE), endosulfan (α- and β-EDS) isomers, chlorpyrifos (CPF), dacthal (DAC) and phenolic compounds, such as 4-nonylphenol (4-NP) and its precursors nonylphenol polyethoxylates (NP1EO and NP2EO) and bisphenol A (BPA), in polar cod sampled in and outside Bessel Fjord (NE Greenland). Linear regressions between target contaminants and morphological parameters (age, length, weight, gonad- and hepato-somatic indices and Fulton K) have been also evaluated. Polar cod collected at shelf had higher average concentrations of BPA, NP1EO, NP2EO and 4-NP (muscle: 6.2, 13.2, 8.9 and 1.9 ng/g w.w., respectively; liver: 5.8, 7.5, 5.2 and 0.9 ng/g w.w. respectively), than fjord’s specimens (muscle: 3.5, 9.1, 3.9 and 1.0 ng/g w.w., respectively; liver: 2.4, 5.3, 2.9 and 1.1 ng/g w.w. respectively). ΣHCHs, ΣEDSs, ΣDDTs, CPF and DAC, were more accumulated in the polar cod from the fjord (average amount in muscle: 9.1, 4.8, 7.9, 3.8 and 2.8 ng/g w.w., respectively; average amount in the liver: 11.2, 9.0, 3.8, 5.9 and 4.9 ng/g w.w., respectively) than shelf’s ones (average amount in muscle 3.9, 4.5, 4.2, 0.9 and 1.2 ng/g w.w., respectively; average amount in liver 7.8, 6.3, 2.1, 3.4 and 2.5 ng/g w.w., respectively). The comparison between the concentration of target contaminants and morphologic parameters suggested a different exposure of polar cod occupying the fjord and shelf habitats, due to a combination of genetic and dietary differences, climate change effects and increased human activities
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