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1.
Mar Pollut Bull ; 145: 564-568, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590825

RESUMO

The brown alga Sargassum furcatum and three families of amphipods (Ampithoidae, Caprellidae and Hyalidae) associated to that algae were evaluated as bioindicators of petroleum hydrocarbons input into the marine environment of São Sebastião Channel, in southeastern region of Brazil. The n-alkanes pattern were mainly associated with the natural composition of the macroalgae and amphipods, although some indicatives of petroleum hydrocarbons such as unresolved complex mixture and the no predominance of odd over even n-alkanes have been observed in some samples. Total PAHs ranged from 33.4 to 2010 ng g-1 dry weight with the predominance of low molecular weight PAHs, mostly of naphthalene and alkyl-naphthalenes, which also suggested petroleum input. Even in low concentration, Sargassum furcatum and amphipods species studied seems to be good indicators of the introduction of petroleum hydrocarbons.


Assuntos
Anfípodes/química , Hidrocarbonetos/análise , Sargassum/química , Alga Marinha/química , Poluentes Químicos da Água/análise , Alcanos/análise , Anfípodes/efeitos dos fármacos , Animais , Brasil , Biomarcadores Ambientais , Monitoramento Ambiental , Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Sargassum/efeitos dos fármacos , Alga Marinha/efeitos dos fármacos
2.
Bull Environ Contam Toxicol ; 103(2): 255-260, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31062039

RESUMO

Ecological effects of gold nano-particles (AuNP) are examined due to growing use in consumer and industrial materials. This study investigated uptake and movement of AuNPs through an aquatic food chain. Simple (single-species) and diverse (multi-species) periphyton communities were exposed to AuNP (0, 100, 500 µg L-1 treatments). AuNP quickly aggregated and precipitated from the water column, suggesting it is an insignificant route of AuNP exposure even at elevated concentrations. Gold was measured in 100 and 500 µg L-1 periphyton treatments. Gold accumulation was similar between periphyton treatments, suggesting physical processes were important for AuNP basal accumulation. Hyalella azteca and Lymnea stagnalis whole body tissue analysis indicated gold accumulation may be attributed to different feeding mechanisms, general versus selective grazing, respectively. Results suggest trophic transfer of AuNP is organism specific and aggregation properties of AuNP are important when considering fate of nano-particles in the environment and movement through aquatic food webs.


Assuntos
Anfípodes/efeitos dos fármacos , Ouro/análise , Lymnaea/efeitos dos fármacos , Nanopartículas Metálicas/análise , Perifíton/efeitos dos fármacos , Poluentes Químicos da Água/análise , Anfípodes/química , Animais , Exposição Dietética , Cadeia Alimentar , Lymnaea/química , Especificidade da Espécie
3.
Environ Sci Pollut Res Int ; 25(28): 28725-28729, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30109688

RESUMO

Using Fourier transform infrared spectroscopy (FT-IR) measurements and comparing the spectrum peaks (range 4000-600 cm-1) with reference spectra database and instrument libraries, we observed new evidence of the ingestion of microplastic particles analyzing the digestive tracts of Talitrus saltator. Specimens, sampled in central Italy, probably ingested the particles with natural detritus. Since worldwide many species of invertebrates and vertebrates (e.g., birds) feed on Amphipoda along coastal ecosystems, we hypothesized that microplastic in these crustaceans can be accumulated along the food chain.


Assuntos
Anfípodes/química , Exposição Dietética/análise , Plásticos/análise , Poluentes Químicos da Água/análise , Animais , Ecossistema , Ecotoxicologia/métodos , Monitoramento Ambiental/métodos , Cadeia Alimentar , Conteúdo Gastrointestinal , Itália , Polietileno/análise , Espectroscopia de Infravermelho com Transformada de Fourier
4.
PLoS One ; 13(4): e0196461, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29702662

RESUMO

Insect growth regulator insecticides mimic the action of hormones on the growth and development of insect pests. However, they can affect the development of non-target arthropods. In the present study, we tested the effects of the growth regulator insecticide fenoxycarb on several endpoints in the freshwater crustacean Gammarus fossarum (Amphipoda). Females carrying embryos in their open brood pouch were exposed to 50 µg L-1 fenoxycarb throughout the entire oogenesis (i.e. 21 days). After exposure, newborn individuals from exposed embryos were removed from the maternal open brood pouch for lipidomic analysis, while males were added to assess the reproductive success. After fertilization, the lipid profile, energy reserve content (lipids, proteins and glycogen), and activity of phenoloxidase - an enzyme involved in the immune response - were measured in females. No significant effect of fenoxycarb exposure was observed on the lipid profile of both newborn individuals and females, while reproductive success was severely impaired in exposed females. Particularly, precopulatory behavior was significantly reduced and fertilized eggs were unviable. This study highlighted the deleterious effects of the insect growth regulator fenoxycarb on gammarid reproduction, which could have severe repercussions on population dynamics.


Assuntos
Anfípodes/química , Anfípodes/efeitos dos fármacos , Lipídeos/química , Fenilcarbamatos/efeitos adversos , Animais , Embrião não Mamífero , Exposição Ambiental , Feminino , Água Doce , Glicogênio/química , Hormônios/química , Sistema Imunitário/efeitos dos fármacos , Inseticidas/efeitos adversos , Masculino , Monofenol Mono-Oxigenase/química , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Dinâmica Populacional , Proteínas/química , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/química , Zigoto/efeitos dos fármacos
5.
Sci Total Environ ; 616-617: 1199-1207, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29079095

RESUMO

The aim of this study was to investigate the concentrations of the metals Ag, Cd, Cu, Mn, Mo, Pb, Pt and Zn in sediments and amphipods along a 100m transect downstream of three different combined sewer overflows (CSOs). Moreover, the study was implemented to better understand the biological availability of metals downstream of CSOs as well as to identify a potential risk of CSOs for benthic or pelagic biota. Samples were taken at downstream sampling sites, which were 1, 5, 10, 20, 50 and 100m away from the outlets of the CSOs. An upstream-located sampling site each was used as reference for the respective transect. Additionally, sediments in two retention zones, located between the CSOs and the receiving creeks were analyzed. All downstream located creek sediments showed a similar metal pattern. Metal concentrations were found to be highest within the first 20m of the creek sediments. Elevated metal concentrations were also detected in the sediments of the retention zones. Metal accumulation in the amphipods was different at all three locations, but highest levels were always found downstream of the sediment accumulation hot spots. This might indicate that the metals were remobilized and became available for the amphipods further downstream of the CSOs. Although the general contamination pattern with respect to each reference site was similar, the degree of contamination was different at each location as demonstrated by anthropogenic enrichment factors. The discharge frequency as well as anthropogenic influences from upper reaches appear to be the most important factors for high metal concentrations in the sediments. Accordingly, in one case high background concentrations in combination with the CSO lead to an exceedance of the predicted effect level of Zn for aquatic organisms. Therefore, sediment contamination should be included in risk assessment when constructing CSOs to protect aquatic life.


Assuntos
Anfípodes/química , Monitoramento Ambiental , Sedimentos Geológicos/química , Metais/análise , Poluentes Químicos da Água/análise , Animais , Organismos Aquáticos , Biota , Eliminação de Resíduos Líquidos
6.
Environ Sci Pollut Res Int ; 25(12): 11281-11294, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28624948

RESUMO

Industrialization has left large surfaces of contaminated soils, which may act as a source of pollution for contiguous ecosystems, either terrestrial or aquatic. When polluted sites are recolonized by plants, dispersion of leaf litter might represent a non-negligible source of contaminants, especially metals. To evaluate the risks associated to contaminated leaf litter dispersion in aquatic ecosystems, we first measured the dynamics of metal loss from leaf litter during a 48-h experimental leaching. We used aspen (Populus tremula L.), a common tree species on these polluted sites, and collected leaf litter on three polluted sites (settling pond of a former steel mill) and three control sites situated in the same geographic area. Then, toxicity tests were carried out on individuals of a key detritivore species widely used in ecotoxicology tests, Gammarus fossarum (Crustacea, Amphipoda), with uncontaminated and contaminated leaf litter leachates, using a battery of biomarkers selected for their sensitivity to metallic stress. Leaf litters collected on polluted sites exhibited not only significantly higher cadmium and zinc concentrations but also lower lignin contents. All leaf litters released high amounts of chemical elements during the leaching process, especially potassium and magnesium, and, in a lesser extent, phosphorus, calcium, and trace metals (copper, cadmium, and zinc but not lead). Toxicity tests revealed that the most important toxic effects measured on G. fossarum were due to leaf litter leachates by themselves, whatever the origin of litter (from polluted or control sites), confirming the toxicity of such substances, probably due to their high content in phenolic compounds. Small additional toxic effects of leachates from contaminated leaf litters were only evidenced on gammarid lipid peroxidation, indicating that contaminated leaf litter leachates might be slightly more toxic than uncontaminated ones, but in a very reduced manner. Further studies will be required to verify if these patterns are generalizable to other species and to investigate the effects of contaminated leaf litter ingestion by consumers on aquatic food webs. Nevertheless, our results do not permit to exclude potential chronic effects of an exposure to contaminated leaf litter leachates in aquatic ecosystems.


Assuntos
Cádmio/análise , Ecotoxicologia/métodos , Metais/análise , Fósforo/análise , Folhas de Planta/química , Zinco/análise , Anfípodes/química , Anfípodes/efeitos dos fármacos , Animais , Ecossistema , Água Doce , Metais/química , Testes de Toxicidade
7.
Environ Toxicol Chem ; 36(11): 3057-3064, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28577330

RESUMO

Pyrethroids are insecticides widely used to control pests and disease vectors in residential areas and agricultural lands. Pyrethroids are emerging pollutants, and their use is a growing concern because of their toxicity potential to aquatic organisms. Todos Santos Bay and the Punta Banda estuary, 2 coastal bodies located to the south of the Southern California Bight, were studied to establish a baseline of the current conditions of pollution by pyrethroids and fipronil. Eight pyrethroids, along with fipronil and its 2 metabolites, were determined in effluents from wastewater-treatment plants (n = 3), surface sediments (n = 32), and 3 locations with mussels (Mytilus californianus, n = 9). Bifenthrin, permethrin, and cypermethrin were the most common pyrethroids found in the study areas and were widespread in sediments, mussels, and wastewater-treated effluents. Fipronil and its metabolites were detected in mussels and wastewater-treated effluents only. Total pyrethroid concentrations in sediments ranged from 0.04 to 1.95 ng/g dry weight in the Punta Banda estuary (n = 13) and from 0.07 to 6.62 ng/g dry weight in Todos Santos Bay (n = 19). Moreover, total pyrethroids in mussels ranged from 1.19 to 6.15 ng/g wet weight. Based on the toxic unit data calculated for pyrethroids and fipronil for Eohaustorius estuarius and Hyalella azteca, little to no impact is expected to the benthic population structure. Environ Toxicol Chem 2017;36:3057-3064. © 2017 SETAC.


Assuntos
Sedimentos Geológicos/química , Inseticidas/análise , Pirazóis/análise , Piretrinas/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Anfípodes/química , Animais , Baías/química , Estuários , México , Permetrina/análise , Resíduos de Praguicidas/análise
8.
Anal Bioanal Chem ; 409(16): 3969-3991, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28417180

RESUMO

A highly multiplexed liquid chromatography mass spectrometry-selected reaction monitoring (SRM)-based assay for determination of 40 potential protein biomarkers from Gammarus fossarum, an ecotoxicological relevant species, was described. The assay relies on 71 stable isotope-labeled reported peptide standards for the quantitation of proteins of interest in relation to essential physiological functions such as reproductive cycle, defense mechanism, and enzymes involved in homeostasis process and in energy. A direct linear relationship between the spiked peptide concentration and the area under the peak was clearly demonstrated in biological extracts. Precision and accuracy were determined to be between 1.1 and 21% and between 79 and 120%, respectively, depending on the selected protein in a few samples after optimization of digestion conditions. The validity of the assay was documented for several biomarkers linked with reproduction and the molting process was performed with the assessment of protein levels throughout contrasted physiological process (sex, reproductive status). This assay is easy to use, robust, sensitive, and has high-throughput capabilities. The proposed strategy may be extended to any non-model organisms relevant in environmental science. Graphical abstract ᅟ.


Assuntos
Anfípodes/química , Proteínas de Artrópodes/análise , Espectrometria de Massas em Tandem/métodos , Anfípodes/fisiologia , Animais , Proteínas de Artrópodes/metabolismo , Cromatografia Líquida/métodos , Monitoramento Ambiental , Feminino , Masculino , Muda , Reprodução
9.
Fish Shellfish Immunol ; 63: 196-200, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28212833

RESUMO

Dietary administration of immunostimulants showed promising results for elevation of immune responses and disease resistance. The aim of the present study was to investigate the effects of dietary Pontogammarus (Pontogammarus maeoticus) extract on innate immune response, stress resistance, feed intake and growth performance of the Caspian roach fingerling. Two levels of P. maeoticus extract dilution with distilled water 1:25 [T1] and 1:50 [T2] were prepared. Experimental diets were prepared by top-spraying the basal diet with equal amount (2%) of diluted extracts. One hundred and eighty Caspian roach fingerlings (4.30 ± 0.10 g) were supplied, stocked in nine 100-L tanks (three treatment repeated in triplicates) and fed on experimental diets for 8 weeks. At the end of the trial, serum innate immune parameters (Total Ig, ACH50, and lysozyme activity), resistance against salinity stress, feed intake and growth parameters were measured. The results revealed remarkable increase of innate immune parameters and resistance against salinity stress in roach fed P. maeoticus extracts (P < 0.05). Also, growth performance and food intake were notably improved in P. maeoticus extracts fed fish (P < 0.05). These results revealed beneficial effects of P. maeoticus extract on innate immune response, resistance, feed intake as well as growth performance of the Caspian roach.


Assuntos
Anfípodes/química , Cyprinidae/fisiologia , Dieta/veterinária , Suplementos Nutricionais , Imunidade Inata , Salinidade , Ração Animal/análise , Animais , Cyprinidae/crescimento & desenvolvimento , Cyprinidae/imunologia , Comportamento Alimentar/fisiologia , Estresse Fisiológico/fisiologia
10.
J Proteomics ; 146: 207-14, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27404005

RESUMO

UNLABELLED: In environmental science, omics-based approaches are widely used for the identification of gene products related to stress response. However, when dealing with non-model species, functional prediction of genes is challenging. Indeed, functional predictions are often obtained by sequence similarity searches and functional data from phylogenetically distant organisms, which can lead to inaccurate predictions due to quite different evolutionary scenarios. In oviparous females, vitellogenin production is vital for embryonic development, ensuring population viability. Its abnormal presence in fish male organisms is commonly employed as a biomarker of exposure to xenoestrogens, named endocrine disruptors. Here, in the freshwater amphipod Gammarus fossarum, we identified vitellogenin proteins by means of a proteome temporal dynamics analysis during oogenesis and embryogenesis. This exhaustive approach allows several functional molecular hypotheses in the oogenesis process to be drawn. Moreover, we revealed an unsuspected diversity of molecular players involved in yolk formation as eight proteins originating from different families of the large lipid transfer protein superfamily were identified as "true vitellogenins". BIOLOGICAL SIGNIFICANCE: In non-model species, next generation sequencing technologies development enables quickly deciphering gene and protein sequences but accuracy of associated functional prediction remains to be established. Here, in the crustacean Gammarus fossarum, a key sentinel species in freshwater biomonitoring, we identified key molecular players involved in the female reproduction by studying the proteome dynamics of ovaries and embryos. An unsuspected diversity of vitellogenin proteins was evidenced. These proteins being vital for offspring development, their high diversity may be advantageous for the organism's reproduction. Phylogenetic analysis showed that some forms are true vitellogenin orthologs while others are included in the apolipoprotein family, a paralogous group from the vitellogenin family. Among crustaceans, Gammarus fossarum is the first documented case where diverse protein families are involved in the yolk formation process.


Assuntos
Anfípodes/química , Sequenciamento de Nucleotídeos em Larga Escala , Proteômica/métodos , Espécies Sentinelas/fisiologia , Vitelogeninas/análise , Anfípodes/fisiologia , Animais , Proteínas do Ovo/análise , Embrião não Mamífero/química , Monitoramento Ambiental , Feminino , Variação Genética , Ovário/química
11.
J Chromatogr A ; 1456: 217-25, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27324621

RESUMO

An innovative analytical method has been developed to quantify the bioaccumulation in an amphipod crustacean (Gammarus fossarum) of three micropollutants regarded as anthropic-pollution markers: carbamazepine, oxazepam, and testosterone. A liquid-liquid extraction assisted by salts, known as QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) was miniaturised and optimised, so it could be adapted to the low mass samples (approximatively 5mg dry weight). For this same reason and in order to obtain good sensitivity, ultra-trace analyses were carried out by means of nanoliquid chromatography. A preconcentration system by on-column trapping was optimised to increase the injection volume. In order to improve both sensitivity and selectivity, the multiple reaction monitoring cubed mode analyses (MRM(3)) were carried out, validated and compared to the classic MRM. To the best of our knowledge, this is the first time that MRM(3) is coupled to nanoliquid chromatography for the analysis and detection of organic micropollutants <300Da. The optimised extraction method exhibited recoveries superior to 80%. The limits of quantification of the target compounds were 0.3, 0.7 and 4.7ng/g (wet weight) for oxazepam, carbamazepine and testosterone, respectively and the limits of detection were 0.1, 0.3 and 2.2ng/g (wet weight), respectively. The intra- and inter-day precisions were inferior to 7.7% and 10.9%, respectively, for the three levels of concentration tested. The analytical strategy developed allowed to obtain limits of quantification lower than 1ng/g (wet weight) and to establish the kinetic bioconcentration of contaminants within G. fossarum.


Assuntos
Anfípodes/química , Poluentes Químicos da Água/análise , Animais , Carbamazepina/análise , Cromatografia Líquida de Alta Pressão , Extração Líquido-Líquido , Masculino , Miniaturização , Nanotecnologia , Oxazepam/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Testosterona/análise
12.
Environ Sci Technol ; 49(1): 103-12, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25478728

RESUMO

This study investigated the role of a permanently manned Australian Antarctic research station (Casey Station) as a source of contemporary persistent organic pollutants (POPs) to the local environment. Polybrominated diphenyl ethers (PBDEs) and poly- and perfluoroalkylated substances (PFASs) were found in indoor dust and treated wastewater effluent of the station. PBDE (e.g., BDE-209 26-820 ng g(-1) dry weight (dw)) and PFAS levels (e.g., PFOS 3.8-2400 ng g(-1) (dw)) in dust were consistent with those previously reported in homes and offices from Australia, reflecting consumer products and materials of the host nation. The levels of PBDEs and PFASs in wastewater (e.g., BDE-209 71-400 ng L(-1)) were in the upper range of concentrations reported for secondary treatment plants in other parts of the world. The chemical profiles of some PFAS samples were, however, different from domestic profiles. Dispersal of chemicals into the immediate marine and terrestrial environments was investigated by analysis of abiotic and biotic matrices. Analytes showed decreasing concentrations with increasing distance from the station. This study provides the first evidence of PFAS input to Polar regions via local research stations and demonstrates the introduction of POPs recently listed under the Stockholm Convention into the Antarctic environment through local human activities.


Assuntos
Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Substâncias Perigosas/análise , Hidrocarbonetos Fluorados/análise , Anfípodes/química , Animais , Regiões Antárticas , Briófitas/química , Poeira/análise , Meio Ambiente , Sedimentos Geológicos/análise , Halogenação , Líquens/química , Perciformes , Fitoplâncton/química , Pesquisa , Poluentes do Solo/análise , Águas Residuárias/análise
13.
Sci Total Environ ; 511: 153-60, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25544334

RESUMO

The development, characterisation and application of a new analytical method for multi-residue PPCP determination in the freshwater amphipod, Gammarus pulex are presented. Analysis was performed using pulverised liquid extraction (PuLE), solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Qualitative method performance offered excellent limits of detection at <20 ng g(-1) for 18 out of 29 compounds. For quantitative application, linearity and precision were considered acceptable for 10 compounds across the ng-µg g(-1) range (R2≥0.99; ≤20% relative standard deviation respectively). The method was applied to the analysis of G. pulex and river water sourced from six tributaries of the River Thames. Carbamazepine, diazepam, nimesulide, trimethoprim and warfarin were determined in G. pulex samples at low ng g(-1) (dry weight) concentrations across these sites. Temazepam and diclofenac were also detected, but were not quantifiable. Six pharmaceuticals were quantified in surface waters across the eight sites at concentrations ranging from 3 to 344 ng L(-1). The possibility for confirmatory detection and subsequent quantification of pharmaceutical residues in benthic organisms such as G. pulex will enable further understanding on the susceptibility and ecological effects of PPCPs in the aquatic environment.


Assuntos
Anfípodes/química , Monitoramento Ambiental/métodos , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Animais , Cromatografia Líquida , Água Doce , Extração em Fase Sólida , Espectrometria de Massas em Tandem
14.
J Chromatogr A ; 1367: 16-32, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25287267

RESUMO

Aquatic ecosystems are continuously contaminated by agricultural and industrial sources. Although the consequences of this pollution are gradually becoming visible, their potential impacts on aquatic ecosystems are poorly known, particularly regarding the risk of bioaccumulation in different trophic levels. To establish a causality relationship between bioaccumulation and disease, experiments on biotic matrices must be performed. In this context, a multi-residue method for the analysis of 35 emerging pollutants in three benthic invertebrates (Potamopyrgus antipodarum, Gammarus fossarum, and Chironomus riparius) has been developed. Because the variation in response of each individual must be taken into account in ecotoxicological studies, the entire analytical chain was miniaturised, thereby reducing the required sample size to a minimum of one individual and scaling the method accordingly. A new extraction strategy based on a modified, optimised and miniaturised "QuEChERS" approach is reported. The procedure involves salting out liquid-liquid extraction of approximately 10-20mg of matrix followed by nano-liquid chromatography-nano electospray ionisation coupled with tandem mass spectrometry. The validated analytical procedure exhibited recoveries between 40 and 98% for all the target compounds and enabled the determination of pollutants on an individual scale in the ng g(-1) concentration. The method was subsequently applied to determine the levels of target analytes in several encaged organisms which were exposed upstream and downstream of an effluent discharge. The results highlighted a bioaccumulation of certain targeted emerging pollutants in three freshwater invertebrates, as well as inter-species differences. 18 out of 35 compounds were detected and eight were quantified. The highest concentrations were measured for ibuprofen in G. fossarum, reaching up to 105 ng g(-1).


Assuntos
Anfípodes/química , Chironomidae/química , Cromatografia Líquida/métodos , Poluentes Ambientais/análise , Gastrópodes/química , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida/economia , Extração Líquido-Líquido , Nanoestruturas , Espectrometria de Massas em Tandem/economia
15.
Ecotoxicol Environ Saf ; 110: 182-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25244686

RESUMO

Gammarids are aquatic amphipods widely used for water quality monitoring. To investigate the copper and cadmium diet-borne metal uptake in Gammarus pulex, we adapted the pulse-chase stable isotopes-based approach to determine the food ingestion rate (IR), the gut retention time (GRT) and the metal assimilation efficiencies (AE). G. pulex were fed with (65)Cu-, (106)Cd-, and (53)Cr-labeled alder leaves for 7.5h and then with unlabeled leaves for 5d. The metal stable isotope contents in the gammarids, leaves, filtered water and periodically collected feces were determined. Chromium was poorly assimilated by the gammarids; thus, Cr was used as an unassimilated tracer. The first tracer defecation occurred before the first feces harvest, indicating a gut passage time of less than 9h. A 24-h GRT and a 0.69gg(-1)d(-1) IR were estimated. The Cd AE value was estimated as 5-47%, depending on the assimilation determination method applied. The Cu AE value could not be evaluated regardless of the determination method used, most likely because of the rapid Cu regulation in gammarids in addition to analytical uncertainties when determining the Cu content in leaves. Application of the Cd AE value in the framework of the biodynamic bioaccumulation model shows that the diet-borne uptake of Cd significantly contributes (66-95%) to the metal bioaccumulation in G. pulex fed with alder leaves.


Assuntos
Anfípodes , Monitoramento Ambiental/métodos , Marcação por Isótopo/métodos , Metais/análise , Metais/farmacocinética , Poluentes Químicos da Água/análise , Anfípodes/química , Anfípodes/metabolismo , Animais , Cádmio/análise , Cádmio/farmacocinética , Isótopos do Cromo/análise , Cobre/análise , Cobre/farmacocinética , Água Doce/análise , Modelos Teóricos , Traçadores Radioativos , Poluentes Químicos da Água/farmacocinética , Poluição da Água/análise
16.
Aquat Toxicol ; 153: 89-97, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24342352

RESUMO

The expression of the yolk protein vitellogenin (Vtg) has been used as a biomarker of feminisation in multiple fish species throughout the world. Since the late 1990s, researchers have attempted to develop similar biomarkers to address whether reproductive endocrine disruption also occurs in the males of invertebrate groups such as the Crustacea. To date, the vast majority of studies investigating Vtg induction in male Crustacea have resulted in negative or inconclusive results, leading researchers to question the utility of Vtg expression as a biomarker in this taxon. This study measured the expression of Vtg genes in two intersex phenotypes (termed internal and external) found in the male amphipod, Echinogammarus marinus, and compared them with those of normal males and females. Males presenting the external intersex phenotype are infected with known feminising parasites and display a variety of feminised traits including oviduct structures on their testes and external female brood plates (oostegites). The internal intersex male phenotype, that displays a pronounced oviduct structure on the testes without the external intersex characteristics, is not parasite infected and it is thought to be a result of environmental contamination. Given their morphology, these phenotypes might be considered highly 'feminised' or 'de-masculinised' and can be utilised to test the suitability of feminisation biomarkers. The E. marinus transcriptome was searched for genes resembling Vtg and two sequences were revealed, that we subsequently refer to as Vtg1 and Vtg2. Results from a high-throughput transcriptomic sequencing screen of gonadal cDNA libraries suggested that very low expression (in this manuscript gene transcription is taken to represent gene expression, although it is acknowledged that in addition to transcription, translation, transcript processing, mRNA stability and protein stability can regulate gene expression) of Vtg1 and Vtg2 in normal males (ESTs=1 and 0 for Vtg1 and Vtg2, respectively), internal intersex males (ESTs=0 for both Vtg sequences) and external intersex males (ESTs=5 and 0 for Vtg1 and Vtg2, respectively). In contrast, the sequencing suggested notable levels of expression of both Vtg genes in females (ESTs=1133 and 84 for Vtg1 and Vtg2, respectively). Subsequent qPCR analysis validates these expression levels, with the signal for Vtg1 and Vtg2 transcripts in all male phenotypes being indistinguishable from that caused by contamination of trace levels of genomic DNA or the low-level amplification non-target sequences. These findings suggest that Vtg expression is not notably induced in highly feminised amphipods and is therefore not an appropriate biomarker of feminisation/de-masculination in crustaceans. We discuss our findings in the context of previous attempts to measure Vtg in male crustaceans and suggest a requirement for more appropriate taxon-specific biomarkers to monitor feminisation in these groups.


Assuntos
Anfípodes/genética , Biomarcadores/análise , Vitelogeninas/genética , Vitelogeninas/metabolismo , Anfípodes/química , Anfípodes/metabolismo , Animais , Feminino , Hepatopâncreas/química , Invertebrados/genética , Invertebrados/metabolismo , Masculino , Ovário/química , Ovário/metabolismo , Testículo/química , Testículo/metabolismo , Transcriptoma
17.
Parasitology ; 140(10): 1310-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23866854

RESUMO

Freshwater gammarids infected with the acanthocephalan parasite Polymorphus minutus show behavioural alterations but also differ from uninfected individuals in their appearance because of the carotenoid-based colouration of the parasite visible through the cuticle. However, it's not clear whether this phenotypic alteration is an adaptation favouring parasite transmission to the definitive host. To test this hypothesis, we investigated the selective preference of mallard towards two prey types: uninfected gammarids on which we applied a dot of inconspicuous brown paint, and uninfected gammarids on which we applied a dot of bright orange paint to mimic the change in appearance due to P. minutus without changes in host behaviour. Mallards showed a significant preference for orange-painted gammarids regardless of how gammarids were distributed (isolated or aggregated). This suggests that parasite's colouration may play a role in enhanced transmission to definitive avian hosts. The role of P. minutus' colouration in the conspicuousness of gammarids has however to be balanced by the extent to which mallards use visual cues to forage in the field. From the perspective of a multidimensional manipulation, this study suggests that the change in appearance may act synergistically with the changes in behaviour to promote transmission to waterbirds.


Assuntos
Acantocéfalos/fisiologia , Anfípodes/parasitologia , Patos/fisiologia , Cadeia Alimentar , Interações Hospedeiro-Parasita , Comportamento Predatório/fisiologia , Acantocéfalos/química , Adaptação Fisiológica , Anfípodes/química , Animais , Comportamento Animal/fisiologia , Carotenoides/metabolismo , Patos/parasitologia
18.
Sci Total Environ ; 463-464: 690-9, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23850659

RESUMO

While chronic acidification of water bodies has been steadily decreasing, episodic acidification continues to affect stream biology by temporarily decreasing pH and mobilizing aluminum. These events are becoming more common as climate change renders more frequent and intense storms and flooding. Throughout Scandinavia, the effects of acidification have been mitigated by liming since the 1980s, but remediation efforts can now be reduced. While transient acidity may reduce fish populations, also other species in streams are affected. In this in-stream study, two macro-invertebrates (Gammarus pulex and Baetis rhodani), both known as salmonid prey organisms, were exposed to snowmelt in six humic brooks with a natural gradient of pH and inorganic monomeric Al (Al(i)). We hypothesize that acid toxicity thresholds can be defined using lethal (mortality) and sublethal (changes in body elemental content) metrics. Periodic observations were made of mortality and whole body concentrations of base cations (BC: Ca, Mg, Na and K) and metals (Al, Fe, Zn and Mn). Mortality increased dramatically at pH<6.0 and Al(i)>15 µg/L for G. pulex and at pH<5.7 and Al(i)>20 µg/L for B. rhodani. No accumulation of Al was found. The invertebrate body Na concentration decreased when pH dropped, suggesting that osmoregulation in both species was affected. In contrast to general BC pattern, Ca concentration in G. pulex and Mg concentration in B. rhodani increased when pH decreased. Although Al(i) strongly correlates to pH, the Al composition of soil and bedrock also influences Al availability, potentially contributing to toxic Al(i) episodes. The estimated values calculated in this study can be used to improve water quality criteria and as thresholds to adjust doses of lime compared to old recommendations in ongoing liming programs. Such adjustments may be critical since both Al(i) and pH levels have to be balanced to mitigate damage to recovering stream ecosystems.


Assuntos
Anfípodes/efeitos dos fármacos , Substâncias Húmicas/análise , Insetos/efeitos dos fármacos , Rios/química , Alumínio/análise , Anfípodes/química , Animais , Concentração de Íons de Hidrogênio , Insetos/química , Estações do Ano , Qualidade da Água
19.
Aquat Toxicol ; 140-141: 106-16, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23770824

RESUMO

This study aimed at investigating the individual and interactive effects of cadmium (Cd) and arsenate (AsV) in Gammarus pulex (Crustacea, Amphipoda) through the use of several biomarkers. Individuals were exposed for 240 h to two concentrations of AsV or Cd alone, and all the possible binary mixtures of these concentrations of AsV and Cd in a complete factorial design. The pattern of the biomarkers' responses to Cd and AsV alone or in mixture was similar in Gammarus pulex, even if the response intensity varied depending on the tested conditions. G. pulex responded to contamination with increased mobilization of the detoxification systems [i.e. γ-glutamyl-cystein ligase activity (GCL), reduced glutathione content (GSH) and metallothionein concentrations (MT)]. This response seems to imply changes in energy reserve utilization (total lipids and proteins are used prior to glycogen reserves), but also a possible energy reallocation from locomotion to detoxification processes. The observed increase in lipid peroxidation could be relied to the increasing gammarid mortality, despite the higher mobilization of detoxification systems. Even if the outcome of the complex interactions between AsV and Cd remains difficult to unravel, such studies are critically important for better assessing the effects of stressors on organisms, populations and communities in a multi-contamination context of ecosystems.


Assuntos
Anfípodes/efeitos dos fármacos , Anfípodes/fisiologia , Arseniatos/toxicidade , Comportamento Animal/efeitos dos fármacos , Cádmio/toxicidade , Poluentes Químicos da Água/toxicidade , Anfípodes/química , Animais , Biomarcadores/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/análise , Metalotioneína/análise , Mortalidade , Proteínas/análise
20.
Aquat Toxicol ; 126: 291-8, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23063068

RESUMO

Differences between the bioavailability of cadmium in a periphyton diet and an artificial laboratory diet (TetraMin(®)) have important consequences for predicting bioaccumulation and toxicity in the freshwater amphipod Hyalella azteca. The assimilation efficiency (AE) of Cd was compared between periphyton and TetraMin(®) at low (1510 and 358 nmol/g ash-free dry mass respectively) and chronically lethal (31,200 and 2890 nmol/g ash-free dry mass respectively) Cd concentrations and in fresh and dry forms using a (109)Cd radiotracer pulse-chase feeding technique. Assimilation efficiency of Cd from periphyton (AE=3-14%) was lower than that for TetraMin(®) (AE=44-86%) regardless of Cd concentration or food form. Ingestion rate (IR) was lower for dry than fresh forms of periphyton (0.042 and 0.16 g AFDM/g H. azteca/day respectively) and TetraMin(®) (0.19 and 0.87 AFDM/g H. azteca/day respectively) and depuration rate (k(e)) did not differ statistically with food type, form or Cd concentration (0.032-0.094 d(-1)). Biokinetic models with parameters of AE, IR and k(e) were used to estimate bioaccumulation from the separate food types. These estimates were compared to those from an independent chronic Cd saturation bioaccumulation model. While the model estimates did not concur, a sensitivity analysis indicated that AE and IR were the most influential biokinetic model parameters for Cd in periphyton and TetraMin(®) respectively. It was hypothesized that AE was underestimated for Cd in periphyton due to a non-adapted gut enzyme system and IR was overestimated for Cd in TetraMin(®) due to an initial rapid ingestion phase in H. azteca's feeding habits. This research demonstrated the importance of using ecologically relevant food types in laboratory experiments and verifying acute biokinetic model predictions of dietary metal contribution with those derived from a chronic exposure which is more representative of a field exposure scenario.


Assuntos
Anfípodes/química , Anfípodes/metabolismo , Cádmio/metabolismo , Dieta , Modelos Biológicos , Poluentes Químicos da Água/metabolismo , Animais , Disponibilidade Biológica , Cádmio/análise , Água Doce , Fatores de Tempo , Poluentes Químicos da Água/análise
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