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1.
Mar Pollut Bull ; 124(1): 21-32, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28688520

RESUMO

The aim of the present study was to evaluate the hazard from shipwrecks on communities by a holistic approach taking into account different effects on biological communities. Multibeam and Remotely Operated Vehicles surveys recorded ecological assessment of fish and benthic species on three shipwrecks flooded during the Second World War on Maërl beds habitats in the strait of Sicily. Pollution levels of a wide range of chemicals of ecotoxicological concern were also measured in sediments and in fish species from different trophic levels. Statistical analysis evidenced significant differences among pollutant levels between both sediments and fish collected in shipwreck sites and controls. Concerning fish, significant effects due to the vessel's cargo type and flooding position are recorded. In spite of that, our results underline that shipwrecks are also a hotspots of biodiversity and a habitat for preservation strategies in marine ecosystems that need to be monitored.


Assuntos
Biodiversidade , Peixes/fisiologia , Sedimentos Geológicos/análise , Navios , Poluição Química da Água/análise , Acidentes , Animais , Organismos Aquáticos/fisiologia , Ecossistema , Itália , Mar Mediterrâneo , Análise Multivariada
2.
Int J Endocrinol ; 2015: 234358, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26074959

RESUMO

Background. Impairments of endocrine system may be associated with exposure to perfluorinated compounds that are able to bind nuclear receptors, including the peroxisome proliferator-activating receptors. Aim of this study was to assess perfluorooctane sulfonate and perfluorooctanoic acid concentrations in children and adolescents at the onset of type 1 diabetes compared to healthy controls. Methods. Forty-four children and adolescents were recruited and subdivided into two groups: (A) 25 subjects with type 1 diabetes and (B) 19 healthy controls. Perfluorinated compounds were measured using high performance liquid chromatography with electrospray ionization tandem mass spectrometry. Nonparametric statistical analysis was performed. Results. Perfluorooctane sulfonate concentrations were significantly higher in patients with type 1 diabetes compared to controls (1.53 ± 1.50 versus 0.55 ± 0.15 ng/mL, resp.; p < 0.001). Multivariate linear regression analysis identified lipid levels as significant predictive factors for perfluorooctane sulfonate levels. Conclusions. Our data suggests that higher serum levels of perfluorooctane sulfonate may be considered a biomarker of exposure and susceptibility to develop type 1 diabetes.

3.
Ecotoxicology ; 23(6): 1055-72, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24838657

RESUMO

Phaeodactylum tricornutum was exposed to various toxic substances (zinc, copper or dodecylbenzenesulfonic acid sodium salt) in accordance with the AlgalToxkit(®) protocol based on the UNI EN ISO 10253 method in order to quantitatively compare the responses obtained by traditional growth-rate inhibition tests with morphological (biovolume) and physiological (chlorophyll-a, phaeophytin ratio) endpoints. A novel approach is proposed for detecting early and sub-lethal effects based on biovolume quantification using confocal microscopy coupled with an image analysis system. The results showed that effects on both biovolume and the photosynthetic complex are sensitive and powerful early warning tools for evaluating sub-lethal effects of exposure. Specifically, biovolume showed significant sensitive and early responses for the tested surfactant. Qualitatively, we also observed structural anomalies and effects on natural auto-fluorescence in exposed cells that also represent potentially useful tools for ecotoxicological studies.


Assuntos
Benzenossulfonatos/toxicidade , Cobre/toxicidade , Diatomáceas/efeitos dos fármacos , Zinco/toxicidade , Diatomáceas/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Fotossíntese/efeitos dos fármacos , Testes de Toxicidade
4.
Mar Pollut Bull ; 76(1-2): 146-57, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24095201

RESUMO

The results of a study on levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), analyzed in terms of HPLC-ESI-MS in water, sediment, macrophyte, bivalve, crustacean and fish samples, are reported here. The aim of the research is to define, for the first time, PFOA/S levels in a heavily human-stressed transitional water ecosystem (Orbetello lagoon, Italy) and evaluate trophic web enrichments and human dietary intakes. The results obtained show that: (i) levels significantly higher than those reported in the literature were found in mussels, clams and crabs; (ii) the river is a significant pollution source; (iii) although absolute levels are relatively low, macroalgae proliferation contributes to redistribute pollutants from river-affected areas throughout the entire lagoon basin; (iv) to the best of our current knowledge, water-filtering species considered in this study are the most exposed to PFOA/S pollution; (v) human daily dietary intakes of PFOA/S through Slow Food-endorsed product consumption are below maximum tolerable levels suggested by the EFSA.


Assuntos
Ecossistema , Exposição Ambiental/estatística & dados numéricos , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Dieta/estatística & dados numéricos , Cadeia Alimentar , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Itália
5.
Food Chem ; 140(1-2): 197-203, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23578633

RESUMO

Despite the health risks associated with perfluorinated compounds (PFC) exposure and the detection of these compounds in many countries around the world, little is known on their occurrence in Italy. The results of a study on levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), analysed by HPLC-ESI-MS, in human milk and food samples from the city of Siena and its province (central Italy) are here reported. PFOS was found in 13 out of 49 breast milk samples (0.76±1.27 ng/g), while PFOA was detected in one sample (8.04 ng/g). Only PFOS was found in food samples. Fish were the most contaminated samples (7.65±34.2 ng/g); mean concentrations in meat and milk and dairy products were similar (1.43±7.21 ng/g and 1.35±3.45 ng/g, respectively). In all cereal-based food, eggs, vegetables, honey and beverages PFOS concentration was

Assuntos
Ácidos Alcanossulfônicos/análise , Caprilatos/análise , Poluentes Ambientais/análise , Fluorocarbonos/análise , Contaminação de Alimentos/análise , Leite Humano/química , Adulto , Exposição Ambiental , Feminino , Humanos , Itália , Projetos Piloto
6.
FEMS Microbiol Lett ; 343(2): 105-12, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23521025

RESUMO

Four bacterial strains capable of growing in the presence of tannic acid as sole carbon and energy source were isolated from olive mill waste mixtures. 16S rRNA gene sequencing assigned them to the genus Klebsiella. The most efficient strain, Klebsiella sp. strain C2A, was able to degrade 3.5 g L(-1) tannic acid within 35 h with synthesizing gallic acid as main product. The capability of Klebsiella sp. strain C2A to produce tannase was evidenced at high concentrations of tannic acid up to 50 g L(-1) . The bacteria adapted to the toxicity of tannic acids by an increase in the membrane lipid fatty acids degree of saturation, especially in the presence of concentrations higher than 20 g L(-1) . The highly tolerant and adaptable bacterial strain characterized in this study could be used in bioremediation processes of wastes rich in polyphenols such as those derived from olive mills, winery or tanneries.


Assuntos
Klebsiella/efeitos dos fármacos , Klebsiella/metabolismo , Taninos/metabolismo , Taninos/farmacologia , Hidrolases de Éster Carboxílico/metabolismo , Membrana Celular/metabolismo , Klebsiella/classificação , Klebsiella/genética , Klebsiella/isolamento & purificação , Dados de Sequência Molecular , Azeite de Oliva , Fosfolipídeos/metabolismo , Filogenia , Óleos de Plantas , RNA Bacteriano , RNA Ribossômico 16S , Resíduos
7.
Extremophiles ; 13(5): 839-48, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19621207

RESUMO

Two bacterial strains were isolated in the presence of naphthalene as the sole carbon and energy source from sediments of the Orbetello Lagoon, Italy, which is highly contaminated with both organic compounds and metals. 16S rRNA gene sequence analysis of the two isolates assigned the strains to the genera Paenibacillus and Pseudomonas. The effect of different contaminants on the growth behaviors of the two strains was investigated. Pseudomonas sp. ORNaP2 showed a higher tolerance to benzene, toluene, and ethylbenzene than Paenibacillus sp. ORNaP1. In addition, the toxicity of heavy metals potentially present as co-pollutants in the investigated site was tested. Here, strain Paenibacillus sp. ORNaP1 showed a higher tolerance towards arsenic, cadmium, and lead, whereas it was far more sensitive towards mercury than strain Pseudomonas sp. ORNaP2. These differences between the Gram-negative Pseudomonas and the Gram-positive Paenibacillus strain can be explained by different general adaptive response systems present in the two bacteria.


Assuntos
Sedimentos Geológicos/microbiologia , Bactérias Gram-Positivas/metabolismo , Naftalenos/metabolismo , Pseudomonas/metabolismo , Poluentes Químicos da Água/metabolismo , Sequência de Bases , Biodegradação Ambiental , Primers do DNA/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/isolamento & purificação , Itália , Metais Pesados/toxicidade , Dados de Sequência Molecular , Naftalenos/toxicidade , Filogenia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Pseudomonas/efeitos dos fármacos , Pseudomonas/genética , Pseudomonas/isolamento & purificação , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Poluentes Químicos da Água/toxicidade
8.
Extremophiles ; 12(3): 343-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18305894

RESUMO

Bacillus sp. ORAs2 and Pseudomonas sp. ORAs5, two arsenic-resistant bacterial strains previously isolated from sediments of the Orbetello Lagoon, Italy, were tested for their adaptation to mixed contaminants on the level of membrane fatty acid composition. The two bacterial strains were characterized by high levels of arsenic resistance, and Pseudomonas sp. ORAs5 was also shown to be solvent-tolerant. The bacterial strains were exposed to mixtures of two toxic compounds: arsenic at fixed concentrations and toluene in variable amounts or, alternatively, toluene at constant values along with arsenic added at variable concentrations. Both strains react to the contaminants by changing the composition of their membrane fatty acids. Bacillus sp. strain ORAs2 showed a correlation between growth rate decreases and fatty acids degree of saturation increases in both cases, although pointedly in the presence of 1, 2, and 3 mM of toluene and different additions of arsenic, counteracting membranes fluidity induced by toxic compounds. In Pseudomonas sp. ORAs5, adaptive changes in membrane composition was observed both in terms of increases in the degree of saturation and in the trans/cis ratio of unsaturated fatty acids in the presence of varying toluene and constant arsenic concentrations, whereas only minor changes occurred with increasing arsenic and constant toluene concentrations. Thus, on the level of membrane composition, Bacillus sp. ORAs2 showed a higher potential for adaptation to the presence of mixed pollutants, suggesting its probable suitability for bioremediation purposes.


Assuntos
Arsênio/toxicidade , Bacillus/efeitos dos fármacos , Ácidos Graxos/metabolismo , Lipídeos de Membrana/metabolismo , Pseudomonas/efeitos dos fármacos , Tolueno/toxicidade , Poluentes Químicos da Água/toxicidade , Adaptação Fisiológica , Arsênio/metabolismo , Bacillus/crescimento & desenvolvimento , Bacillus/metabolismo , Biodegradação Ambiental , Relação Dose-Resposta a Droga , Itália , Fluidez de Membrana/efeitos dos fármacos , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/metabolismo , Tolueno/metabolismo , Poluentes Químicos da Água/metabolismo
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