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Francesco Regoli - One of the best experts on this subject based on the ideXlab platform.
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arsenic speciation in tissues of the mediterranean Polychaete sabella spallanzanii
Environmental Toxicology and Chemistry, 2004Co-Authors: Daniele Fattorini, Francesco RegoliAbstract:Arsenic toxicity is strictly related to its chemical form and marine organisms are known to accumulate this element mostly as organoarsenic nontoxic molecules. Contrasting with this general trend, the presence of moderately toxic to toxic arsenic compounds recently has been reported in some Polychaete species, showing a completely different profile of represented chemical species. In this work the presence and distribution of arsenic were characterized in the Mediterranean Polychaete Sabella spallanzanii, by analyzing total levels in different tissues and subcellular fractions and the occurrence of various arsenical compounds. Further investigations on arsenic accumulation in S. spallanzanii were based on the capability of this species to regenerate the branchial crown both in laboratory and field conditions. Though basal levels of arsenic in the thorax were similar to those already described for most Polychaetes and invertebrate species, branchial crown revealed a remarkable accumulation of this element with concen- trations higher than 1,000 mg/g. Arsenic mainly was localized in a soluble form within the cytosol and dimethyl-arsinate (DMA) appeared the most represented chemical species. Experiments on bioaccumulation of arsenic in regenerating branchial crowns confirmed the environmental origin of this element and the time-dependent appearance of various As compounds suggested a methylation pathway more than a degradation process for the elevated content of DMA. The accumulation of this moderately toxic compound in the more vulnerable tissues of the Polychaete might represent an antipredatory strategy, as indicated by some feeding trials where fish ate the thorax but rejected the branchial crowns. Keywords—Arsenic compounds Dimethyl-arsinate Chemical speciation Polychaetes Sabella spallanzanii
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Total content and chemical speciation of arsenic in the Polychaete Sabella spallanzanii.
Marine environmental research, 2004Co-Authors: Daniele Fattorini, Raffaella Bocchetti, Stefano Bompadre, Francesco RegoliAbstract:An unusual feature has been observed in Polychaetes regarding their capacity to accumulate high levels of relatively toxic forms of arsenic in specific tissues. Basal levels of arsenic and distribution of its compounds were investigated in tissues of the Mediterranean Polychaete Sabella spallanzanii. Particularly high concentrations were measured in the branchial crown (1036+/-136 microg/g d.w.) and chemical speciation revealed that the predominant form was the relatively toxic dimethylarsinate (DMA). These data suggest a potential role of As as anti-predatory strategy in Polychaetes.
Daniele Fattorini - One of the best experts on this subject based on the ideXlab platform.
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arsenic speciation in tissues of the mediterranean Polychaete sabella spallanzanii
Environmental Toxicology and Chemistry, 2004Co-Authors: Daniele Fattorini, Francesco RegoliAbstract:Arsenic toxicity is strictly related to its chemical form and marine organisms are known to accumulate this element mostly as organoarsenic nontoxic molecules. Contrasting with this general trend, the presence of moderately toxic to toxic arsenic compounds recently has been reported in some Polychaete species, showing a completely different profile of represented chemical species. In this work the presence and distribution of arsenic were characterized in the Mediterranean Polychaete Sabella spallanzanii, by analyzing total levels in different tissues and subcellular fractions and the occurrence of various arsenical compounds. Further investigations on arsenic accumulation in S. spallanzanii were based on the capability of this species to regenerate the branchial crown both in laboratory and field conditions. Though basal levels of arsenic in the thorax were similar to those already described for most Polychaetes and invertebrate species, branchial crown revealed a remarkable accumulation of this element with concen- trations higher than 1,000 mg/g. Arsenic mainly was localized in a soluble form within the cytosol and dimethyl-arsinate (DMA) appeared the most represented chemical species. Experiments on bioaccumulation of arsenic in regenerating branchial crowns confirmed the environmental origin of this element and the time-dependent appearance of various As compounds suggested a methylation pathway more than a degradation process for the elevated content of DMA. The accumulation of this moderately toxic compound in the more vulnerable tissues of the Polychaete might represent an antipredatory strategy, as indicated by some feeding trials where fish ate the thorax but rejected the branchial crowns. Keywords—Arsenic compounds Dimethyl-arsinate Chemical speciation Polychaetes Sabella spallanzanii
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Total content and chemical speciation of arsenic in the Polychaete Sabella spallanzanii.
Marine environmental research, 2004Co-Authors: Daniele Fattorini, Raffaella Bocchetti, Stefano Bompadre, Francesco RegoliAbstract:An unusual feature has been observed in Polychaetes regarding their capacity to accumulate high levels of relatively toxic forms of arsenic in specific tissues. Basal levels of arsenic and distribution of its compounds were investigated in tissues of the Mediterranean Polychaete Sabella spallanzanii. Particularly high concentrations were measured in the branchial crown (1036+/-136 microg/g d.w.) and chemical speciation revealed that the predominant form was the relatively toxic dimethylarsinate (DMA). These data suggest a potential role of As as anti-predatory strategy in Polychaetes.
Wenhong Fan - One of the best experts on this subject based on the ideXlab platform.
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Mercury and methylmercury bioaccumulation in a contaminated bay.
Marine Pollution Bulletin, 2019Co-Authors: Wenhong Fan, Zhiwei Shi, Cheng Tan, Minming Cui, Shichuan Tang, Guangle Qiu, Xinbin FengAbstract:Abstract The bioaccumulation and the main source of total Hg (THg) and methylmercury (MMHg) in the deposit-feeding Polychaete Neanthes japonica collected in Jinzhou Bay, China, were investigated. Compared with the historical data, THg bioaccumulation in Polychaetes collected in sediment of Jinzhou Bay was distinctly higher due to higher sediment THg concentration, but MMHg bioaccumulation was significantly lower. THg accumulation in Polychaetes mainly derived from its accumulation in sediment. However, MMHg bioaccumulation in Polychaetes did not correlate with Hg concentration in sediment. Besides sediment ingestion, MMHg accumulation in Polychaetes may partially source from the process of in vivo transformation. The in vivo Hg methylation may take place in Polychaetes, according to the excellent correlation between MMHg concentration and THg and inorganic Hg concentration in Polychaetes. The biochemical characters in Polychaete body, the oxidation-reduction environment and the microbial activity in Polychaete gut may be beneficial to in vivo Hg methylation.
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metal pollution in a contaminated bay relationship between metal geochemical fractionation in sediments and accumulation in a Polychaete
Environmental Pollution, 2014Co-Authors: Wenhong Fan, Wenxiong WangAbstract:Abstract Jinzhou Bay in Northern China has been seriously contaminated with metals due to the impacts of smelting activities. In this study, we investigated the relationship between metal accumulation in a deposit-feeding Polychaete Neanthes japonica and metal concentration and geochemical fractionation (Cd, Cu, Pb, Zn and Ni) in sediments of Jinzhou Bay. Compared with the historical data, metals in the more mobile geochemical fraction (exchangeable and carbonate fractions) were gradually partitioned into the more stable fraction (Fe–Mn oxides) over time. Metal concentration and geochemical fractionation in sediment significantly affected metal bioavailability and accumulation in Polychaetes, except for Ni. Metal accumulation in Polychaetes was significantly influenced by Fe or Mn content, and to a lesser degree by organic matter. Prediction of metal bioaccumulation in Polychaetes was greatly improved by normalizing metal concentrations to Mn content in sediment. The geochemical fractionation of metals in sediments including the exchangeable, organic matter and Fe–Mn oxides were important in controlling the sediment metal bioavailability to Polychaetes.
Jean-claude Dauvin - One of the best experts on this subject based on the ideXlab platform.
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Polychaete amphipod ratios an approach to validating simple benthic indicators
Ecological Indicators, 2016Co-Authors: Jean-claude Dauvin, H. Andrade, Jose Antonio Delaossacarretero, Yoana Delpilarruso, R. RieraAbstract:Among the macro-invertebrates used for the assessment of soft-bottom communities, most Polychaetes are classified as tolerant/opportunistic to pollution while amphipods are considered as sensitive. These taxa have been used in several ecological indices, such as the simple abundance ratio between Polychaeta and Amphipoda or the Benthic Opportunist Annelids Amphipods (BO2A) index, to assess the Ecological Quality Status -EcoQs- of soft-bottom communities. In terms of Taxonomic Sufficiency (TS), the Polychaete/amphipod ratio (i.e. at the level of the class/order) has been proved to be effective in identifying major changes in benthic communities following disturbances. However, an underlying issue is to assess the acceptable TS limit value needed to state accurately the quality of the benthic environment. We tested three indices using 18 series of observations carried out in five north-eastern Atlantic and Mediterranean zones impacted by oil spills, oil and gas production, brine and urban sewage, harbours and aquaculture farms within impacted and control areas. Similar results to BO2A were obtained when limiting the TS at the level of Polychaete opportunistic families, which required a lower degree of taxonomic expertise, and classifying all amphipods as sensitive taxa. In such a way that the EcoQs given by the BPOFA (Benthic Polychaete Opportunistic Families Amphipods) was very similar to those given by the BO2A (Benthic Opportunistic Annelids Amphipods).
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Polychaete/amphipod ratios: An approach to validating simple benthic indicators
Ecological Indicators, 2016Co-Authors: Jean-claude Dauvin, H. Andrade, J.a. De-la-ossa-carretero, Y. Del-pilar-ruso, R. RieraAbstract:Among the macro-invertebrates used for the assessment of soft-bottom communities, most Polychaetes are classified as tolerant/opportunistic to pollution while amphipods are considered as sensitive. These taxa have been used in several ecological indices, such as the simple abundance ratio between Polychaeta and Amphipoda or the Benthic Opportunist Annelids Amphipods (BO2A) index, to assess the Ecological Quality Status -EcoQs- of soft-bottom communities. In terms of Taxonomic Sufficiency (TS), the Polychaete/amphipod ratio (i.e. at the level of the class/order) has been proved to be effective in identifying major changes in benthic communities following disturbances. However, an underlying issue is to assess the acceptable TS limit value needed to state accurately the quality of the benthic environment. We tested three indices using 18 series of observations carried out in five north-eastern Atlantic and Mediterranean zones impacted by oil spills, oil and gas production, brine and urban sewage, harbours and aquaculture farms within impacted and control areas. Similar results to BO2A were obtained when limiting the TS at the level of Polychaete opportunistic families, which required a lower degree of taxonomic expertise, and classifying all amphipods as sensitive taxa. In such a way that the EcoQs given by the BPOFA (Benthic Polychaete Opportunistic Families Amphipods) was very similar to those given by the BO2A (Benthic Opportunistic Annelids Amphipods).
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Short-term impact of bait digging on intertidal macrofauna of tidal mudflats around the Kneiss Islands (Gulf of Gabès, Tunisia)
Aquatic Living Resources, 2015Co-Authors: Nawfel Mosbahi, Jean-claude Dauvin, Jean-philippe Pezy, Lassad NeifarAbstract:In the Gulf of Gabès (South-eastern Tunisia), Polychaete bait digging is widely practiced for recreational and commercial fishing and is an economically significant activity. The present study aims to assess the short-term effects of intertidal bait digging on macrobenthic communities from the Kneiss Islands. Following a protocol with a control station (not impacted) and three impacted stations for Polychaete collection, the study was conducted during March and April 2015 at spring tides. After digging, immediate significant decreases were observed in the abundance of total macrofauna as well in numerous families of Polychaetes. Control of this activity should be proposed for the future to protect the biodiversity of this intertidal area of high heritage interest.
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Regional patterns of continental shelf Polychaete diversity: examples for the North Sea, English Channel, Irish Sea and Outer Bristol Channel areas
Italian Journal of Zoology, 2011Co-Authors: B. Quiroz-martinez, Jean-claude Dauvin, François G Schmitt, Jean Marie Dewarumez, A. Foveau, C. GarciaAbstract:Polychaetes are a well-represented group in most marine and estuarine environments, both in terms of number of individuals and species; they typically constitute a significant percentage of the total macrofaunal diversity. The aim of our analyses was to characterise the biodiversity and regional distribution patterns of Polychaete assemblages from the continental shelf (0-200 m) of the North Sea, English Channel and Irish Sea. Variations in depth and local distribution of sediment types, amongst other environmental factors, are the main factors affecting the pattern of distribution of benthic Polychaetes. Here we applied and compared different approaches to draw the diversity pattern of this marine invertebrate group on a regional biogeographical scale, and to identify the main factors structuring these patterns.
Xinbin Feng - One of the best experts on this subject based on the ideXlab platform.
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Mercury and methylmercury bioaccumulation in a contaminated bay.
Marine Pollution Bulletin, 2019Co-Authors: Wenhong Fan, Zhiwei Shi, Cheng Tan, Minming Cui, Shichuan Tang, Guangle Qiu, Xinbin FengAbstract:Abstract The bioaccumulation and the main source of total Hg (THg) and methylmercury (MMHg) in the deposit-feeding Polychaete Neanthes japonica collected in Jinzhou Bay, China, were investigated. Compared with the historical data, THg bioaccumulation in Polychaetes collected in sediment of Jinzhou Bay was distinctly higher due to higher sediment THg concentration, but MMHg bioaccumulation was significantly lower. THg accumulation in Polychaetes mainly derived from its accumulation in sediment. However, MMHg bioaccumulation in Polychaetes did not correlate with Hg concentration in sediment. Besides sediment ingestion, MMHg accumulation in Polychaetes may partially source from the process of in vivo transformation. The in vivo Hg methylation may take place in Polychaetes, according to the excellent correlation between MMHg concentration and THg and inorganic Hg concentration in Polychaetes. The biochemical characters in Polychaete body, the oxidation-reduction environment and the microbial activity in Polychaete gut may be beneficial to in vivo Hg methylation.
