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Lead accumulation and elimination in tissues of Prussian carp, Carassius gibelio (Bloch, 1782), after long-term dietary exposure, and depuration periods Texto completo
2013
Łuszczek-Trojnar, Ewa | Drąg-Kozak, Ewa | Popek, Wlodzimierz
We studied the bioaccumulation of lead in selected tissues of Prussian carp Carassius gibelio (Bloch, 1782) during 12 and 24 months exposure to different doses of this metal in feed and the elimination of lead from tissues during the following 12-month depuration period. Lead concentration was determined using atomic absorption spectrometry method. The highest lead concentrations were observed at 2.0 ± 0.54 to 7.4 ± 1.1 mg kg⁻¹ in the kidney, 3.0 ± 0.13 to 5.2 ± 0.17 mg kg⁻¹ in the bone, and 4.5 (±0.4) mg kg⁻¹ in the hepatopancreas of fish from groups exposed to lead dietary concentration from 8 to 49 mg kg⁻¹ for 24 months. The rate of accumulation were generally the highest at the beginning of exposure as evidenced by the highest monthly increments of bioaccumulation observed after 3 months of contamination for muscles, hepatopancreatic gland, intestine, and gills. Also analysis of the monthly increments of lead bioaccumulation in bone tissue and the highly significant coefficients of correlation indicate that the dynamics of accumulation are clearly dependent on dose of exposure. Depuration of accumulated lead from the organs depended mainly on tissue and duration of elimination period. Very rapid depuration was observed in soft tissues such as the intestine or muscles. Very low elimination was observed for scales and bones where until the end of the experiment highly significant lead concentration differences were observed in all groups in relation to the control group. Chronic dietary exposure in the range of 8–49 mg Pb kg⁻¹ resulted in no significant effects on the growth and survival of Prussian carp females.
Mostrar más [+] Menos [-]Monitoring wild pig populations: a review of methods Texto completo
2013
Engeman, R. M. | Massei, G. | Sage, M. | Gentle, M. N.
Wild pigs (Sus scrofa) are widespread across many landscapes throughout the world and are considered to be an invasive pest to agriculture and the environment, or conversely a native or desired game species and resource for hunting. Wild pig population monitoring is often required for a variety of management or research objectives, and many methods and analyses for monitoring abundance are available. Here, we describe monitoring methods that have proven or potential applications to wild pig management. We describe the advantages and disadvantages of methods so that potential users can efficiently consider and identify the option(s) best suited to their combination of objectives, circumstances, and resources. This paper offers guidance to wildlife managers, researchers, and stakeholders considering population monitoring of wild pigs and will help ensure that they can fulfill their monitoring objectives while optimizing their use of resources.
Mostrar más [+] Menos [-]Determining the experimental leachability of copper, lead, and zinc in a harbor sediment and modeling Texto completo
2013
Chatain, Vincent | Blanc, Denise | Borschneck, Daniel | Delolme, Cécile
The potential leaching of pollutants present in harbor sediments has to be evaluated in order to choose the best practices for managing them. Little is known about the speciation and mobility of heavy metals in these specific solid materials. The objective of this paper is to determine and model the leachability of copper, lead, and zinc present in harbor sediments in order to obtain essential new data. The mobility of inorganic contaminants in a polluted harbor sediment collected in France was investigated as a function of physicochemical conditions. The investigation relied mainly on the use of leaching tests performed in combination with mineralogical analysis and thermodynamic modeling using PHREEQC. The modeling phase was dedicated to both confirm the hypothesis formulated to explain the experimental results and improve the determination of the main physico-chemical parameters governing mobility. The experimental results and modeling showed that the release of copper, lead, and zinc is very low with deionized water which is due to the stability of the associated solid phases (organic matter, carbonate minerals, and/or iron sulfides) at natural slightly basic conditions. However, increased mobilization is observed under pH values below 6.0 and above 10.0. This methodology helped to consistently obtain the geochemical parameters governing the mobility of the contaminants studied.
Mostrar más [+] Menos [-]Xenobiotics removal by adsorption in the context of tertiary treatment: a mini review Texto completo
2013
Tahar, Alexandre | Choubert, Jean-Marc | Coquery, Marina
Many xenobiotics, including several pharmaceuticals and pesticides, are poorly treated in domestic wastewater treatment plants. Adsorption processes, such as with activated carbons, could be a solution to curb their discharge into the aquatic environment. As adsorbent-like activated carbon is known to be expensive, identifying promising alternative adsorbent materials is a key challenge for efficient yet affordable xenobiotic removal from wastewaters. As part of the effort to address this challenge, we surveyed the literature on pharmaceutical and pesticide xenobiotics and built a database compiling data from 38 scientific publications covering 65 xenobiotics and 58 materials. Special focus was given to the relevance and comparability of the data to the characteristics of the adsorbent materials used and to the operating conditions of the batch tests inventoried. This paper gives an in-depth overview of the adsorption capacities of various adsorbents. The little data on alternative adsorbent materials, especially for the adsorption of pharmaceuticals, makes it difficult to single out any one activated carbon alternative capable of adsorbing pesticides and pharmaceuticals at the tertiary stage of treatment. There is a pressing need for further lab-scale experiments to investigate the tertiary treatment of discharged effluents. We conclude with recommendations on how future data should best be used and interpreted.
Mostrar más [+] Menos [-]Metal extractability patterns to evaluate (potentially) mobile fractions in periurban calcareous agricultural soils in the Mediterranean area—analytical and mineralogical approaches Texto completo
2013
de Santiago-Martín, Ana | Valverde-Asenjo, Inmaculada | Quintana, Jose R. | Vázquez, Antonio | Lafuente, Antonio L. | González-Huecas, Concepción
A set of periurban calcareous agricultural Mediterranean soils was spiked with a mixture of Cd, Cu, Pb and Zn at two levels within the limit values proposed by current European legislation, incubated for up to 12 months, and subjected to various one-step extraction procedures to estimate mobile (neutral salts) and potentially mobile metal fractions (complexing and acidic extraction methods). The results obtained were used to study metal extractability patterns according to the soil characteristics. The analytical data were coupled with mineralogical investigations and speciation modelling using the Visual Minteq model. The formation of soluble metal-complexes in the complexing extracts (predicted by the Visual Minteq calculations) led to the highest extraction efficiency with complexing extractants. Metal extractability patterns were related to both content and composition of carbonate, organic matter, Fe oxide and clay fractions. Potentially mobile metal fractions were mainly affected by the finest soil fractions (recalcitrant organic matter, active lime and clay minerals). In the case of Pb, scarce correlations between extractable Pb and soil constituents were obtained which was attributed to high Pb retention due to the formation of 4PbCO3·3PbO (corroborated by X-ray diffraction). In summary, the high metal proportion extracted with complexing agents highlighted the high but finite capacity to store potentially mobilizable metals and the possible vulnerability of these soils against environmental impact from metal accumulation.
Mostrar más [+] Menos [-]Seasonal and air mass trajectory effects on dissolved organic matter of bulk deposition at a coastal town in south-western Europe Texto completo
2013
Santos, Patrícia S. M. | Santos, Eduarda B. H. | Duarte, Armando C.
Rainwater contains a complex mixture of organic compounds which may influence climate, terrestrial and maritime ecosystems and thus human health. In this work, the characteristics of DOM of bulk deposition at a coastal town on the southwest of Europe were assessed by UV–visible and three-dimensional excitation–emission matrix fluorescence spectroscopies and by dissolved organic carbon (DOC) content. The seasonal and air mass trajectory effects on dissolved organic matter (DOM) of bulk deposition were evaluated. The absorbance at 250 nm (UV₂₅₀ₙₘ) and integrated fluorescence showed to be positively correlated with each other, and they were also positively correlated to the DOC in bulk deposition, which suggest that a constant fraction of DOM is likely to fluoresce. There was more chromophoric dissolved organic matter (CDOM) present in summer and autumn seasons than in winter and spring. Bulk deposition associated with terrestrial air masses contained a higher CDOM content than bulk deposition related to marine air masses, thus highlighting the contribution of terrestrial/anthropogenic sources.
Mostrar más [+] Menos [-]Responses of juvenile European flounder (Platichthys flesus) to multistress in the Vilaine estuary, during a 6-month survey Texto completo
2013
Evrard, Estérine | Devaux, Alain | Bony, Sylvie | Cachot, Jérôme | Charrier, Grégory | Quiniou, Louis | Laroche, Jean
Physiological and genetic responses of age 0+ Platichthys flesus were investigated in the eutrophicated and moderately contaminated Vilaine estuary, during a 6-month survey. The main objective of this study was to explore the biological responses of fishes during their juvenile period in an estuarine system in order to detect a possible selective pressure induced by the environmental stress. Our results showed a general convergence in physiological responses along the survey: an increase in genotoxicity was associated with an increase in mRNA expression of ATPase and betaine homocysteine methyltransferase. These results could suggest an increase of cellular damage, energetic request, and detoxification rate related to the growing exposure time to stress. Considering the aging of the cohort, the genetic characteristics of the Vilaine flounder cohort came closer to the one observed in a highly stressed system, the Seine estuary, suggesting a potential selective pressure mainly induced by the chemical stress.
Mostrar más [+] Menos [-]Accumulation of heavy metals and antioxidant responses in Vicia faba plants grown on monometallic contaminated soil Texto completo
2013
The purpose of this study was to explore the effects of soil contamination by selected metals (cadmium, copper, nickel, lead or zinc) on the antioxidant response of Vicia faba plants. The levels of the antioxidants: glutathione, proline, non-protein thiols, as well as guaiacol peroxidase and catalase activities were measured in the upperparts of plants. Additionally, the potential bioavailability of metals in the soil and their concentrations in V. faba plants were compared. Treatment with metal caused the problem of an elevation in its bioavailability in soil and its concentration in leaves and stems. The most serious problems seemed to be metal elevations in soil, especially Zn and Ni as well as in the aerial parts of V. faba plants. The antioxidant responses appeared to be metal specific. The elevation of guaiacol peroxidase activity in leaves and stems as well as the proline in leaves was the only more general reaction to metal exposure. Upon analysis of the effects of soil metal contamination on V. faba plants, we recommend the use of some measurements such as guaiacol peroxidase activity and proline level as useful tools in biological monitoring.
Mostrar más [+] Menos [-]The role of transboundary air pollution over Galicia and North Portugal area Texto completo
2013
Borrego, C. | Souto, J. A. | Monteiro, A. | Dios, M. | Fernandez, Aurelio Rodriguez | Ferreira, J. | Saavedra, S. | Casares, J. J. | Miranda, A. I.
In summer, high levels of ozone (O₃) are frequently measured at both Galicia and Northern Portugal air quality monitoring stations, even exceeding the limit values imposed by legislation. This work aims to investigate the origin of these high O₃ concentrations by the application of a chemical transport modelling system over the northwestern area of the Iberian Peninsula. The WRF–CHIMERE modelling system was applied with high resolution to simulate the selected air pollution episodes that occurred simultaneously in Galicia and North Portugal and in order to study both the contribution of local emission sources and the influence of transboundary pollution. Emission inputs have been prepared based on the development of the Portuguese and Galician emission inventories. The obtained results for O₃ have been evaluated and validated against observations. Modelling results show possible contribution of the transboundary transport over the border of two neighbour regions/countries, indicating that the O₃ episode starts over the urban and industrialised area of North coast of Portugal, reaching the maximum peaks over this region; at the same time, O₃ levels increased over Galicia region, where lower concentrations, but still high, were observed. These results pointed out that air quality management should not be driven by political boundaries and highlight the importance of joining efforts between neighbouring countries.
Mostrar más [+] Menos [-]Effects of mono-(2-ethylhexyl) phthalate (MEHP) on chicken germ cells cultured in vitro Texto completo
2013
Guibert, Edith | Prieur, Bérénice | Cariou, Ronan | Courant, Frédérique | Antignac, Jean Philippe | Pain, Bertrand | Brillard, Jean Pierre | Froment, Pascal
In recent decades, many toxicological tests based on in vivo or in vitro models, mainly from mammalian (rat–mouse) and fish species, were used to assess the risks raised by contact or ingestion of molecules of pharmaceutical, agricultural, or natural origin. But no, or few, in vitro tests using other non-mammalian models such as bird have been explored despite their advantages: the embryonic gonads of birds have a high plasticity of development sensitive to estrogen, and sperm production is nearly two times faster than in rodents. Hence, we have established an in vitro culture of germ cells and somatic cells from chicken post-natal testis, and we have evaluated the sensitivity against the endocrine disruptor compound mono-(2-ethylhexyl) phthalate (MEHP) in comparison to previous studies using rodent and human models. After 96 h of exposure in presence of 10 μM MEHP, chicken seminiferous tubules cultures present a structural alteration, a reduction in cell proliferation and in germ cells population. Apoptosis of germ and somatic cells increases in presence of 1 μM MEHP. Furthermore, MEHP does not affect inhibin B and lactate production by Sertoli cells. These results are in accordance with previous studies using rat, mice, or human culture of testicular cells and in similar range of exposures or even better sensitivity for some “end-points” (biological parameters). In conclusion, the establishment of this postnatal testicular cells culture could be considered as an alternative method to in vivo experiments frequently used for evaluating the impact on the terrestrial wildlife species. This method could be also complementary to mammal model due to the limiting number of animals used and its elevated sensitivity.
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