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1.
Arch Environ Contam Toxicol ; 84(1): 73-84, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36566463

RESUMO

The epiphytic lichen Pseudevernia furfuracea was exposed to a simulation of drift deposition rate of the fungicide Fosetyl-Al in an indoor controlled environment by testing two exposure factors: pesticide concentrations (based on the application rates of 4 kg ha-1 and 1.6 kg ha-1) and drop sizes (anti-drift nozzle: 386-484 µm; non-anti-drift nozzle: 159-231 µm) for a total of four treatments. Drift for higher application rate was simulated once and that for the lower one twice to reproduce agricultural practices. Following fungicide spraying, we measured the concentration of Fosetyl and phosphonic acid in lichen thalli, and the response of ecophysiological status parameters. No trace of Fosetyl was quantifiable 4 days after each treatment, being detected only phosphonic acid whose concentrations stayed substantially unchanged for the whole duration of the experiment (40 days) and resulting affected by application rate and not by drop size. Both pesticide concentrations caused a remarkable harmful effect that, however, was statistically significant vs control group only starting from the 20th day of stay in the climatic chamber. The drift associated with the higher rate resulted, on average, to be 83% more effective, with the most affected parameters being membrane integrity, lipid peroxidation and photosynthetic pigments. Because the selected lower rate can be considered a quite low value when compared with the rank of used rates for crop protection, the Fosetyl-Al formulate is classifiable as hazardous for its effect on non-target organisms.


Assuntos
Fungicidas Industriais , Líquens , Fungicidas Industriais/toxicidade
2.
Environ Toxicol Chem ; 42(2): 421-436, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36420672

RESUMO

The present study investigated if new biocomposite materials, polyurethanes (PURs) added with functionalized cellulose fibers, produce potential toxic effects on two target organisms currently used in biomonitoring the quality of two different environmental compartments. Natural fibers were extracted from the species Spartium junceum L., a shrub commonly found in the southern region of the Mediterranean having a high cellulose content. All PURs produced were characterized by Fourier-transform infrared spectroscopy, and their structure was analyzed by scanning electron microscopy. We measured the effects of exposure to aromatic and aliphatic PUR composites (containing or not cellulose fibers) on the aquatic model organism Daphnia magna Straus, a freshwater crustacean (Cladocera), and a biomonitor of air quality, the fruticose epiphytic lichen Pseudevernia furfuracea (L.) Zopf. Leachates from aliphatic PUR composite not containing cellulose are more toxic to D. magna than all others, showing a slight acute toxicity in the case of the shortest exposure (24 h) and a moderate acute toxicity in the longer one (48 h). This effect is most likely due to the presence of free organic ammines and amides, which, in their turn, are immobilized in composites containing cellulosic fibers because of the considerable amount of chemical functional groups. Regarding lichens, both types of aliphatic PURs resulted in a toxic effect. Formulate not added with cellulose strongly promoted fungal peroxidation, whereas that which was functionalized affected the pigment concentration of the algal partner. Our results suggest that the use of cellulose in PUR production, in general, can limit the ecotoxicological effects on both test organisms and reduce the potential environmental impact due to this type of polymer. Environ Toxicol Chem 2023;42:421-436. © 2022 SETAC.


Assuntos
Poliuretanos , Poluentes Químicos da Água , Animais , Poliuretanos/toxicidade , Poliuretanos/química , Daphnia , Organismos Aquáticos , Água Doce , Poluentes Químicos da Água/análise
3.
Arch Environ Contam Toxicol ; 70(3): 506-21, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26546421

RESUMO

Thalli of the lichen Pseudevernia furfuracea were transplanted for 3 months at 32 sites located in and around an industrial area of S Italy whose main anthropogenic sources of atmospheric trace elements are a biomass power plant and vehicular emissions. Meteorological stations were deployed at four sites for finer detection of local wind patterns. The station near the biomass power plant showed a significant S-SE wind component not detectable by measurements made at the regional scale or by the other local meteorological stations. Sb, Sn, and Mo showed a very high degree of covariance and a statistically significant correlation with traffic rate. No element concentrations in the exposed thalli were correlated with distance from the biomass power plant, although Ti and Co concentrations showed a significant correlation with the "Potential Number of Times the Winds coming from the biomass power plant Reach each exposure Site" (PNTWRS). This value is calculated dividing the time (minutes) during the experimental trimester that the wind blows from the power plant into each of the four geographical sides by the time (minutes) the winds passing through the power plant take to reach the exposure sites in each of the four geographical sides.) during the period of thalli transplantation. Moreover, there were significant differences among clusters of sites with different levels of enrichment of Ti, Co, Al, V, and Cu and a "local control" group. These results, together with the high covariance of the Al-Ti and V-Co pairs, indicate an association between the biomass power plant and spatial variation of Ti, Co, Al, and V levels in the transplanted lichens. The nature of the fuels used in the biomass power plant explains the spatial variation of As, Cr, Cu, and Zn concentrations.


Assuntos
Poluentes Atmosféricos/análise , Ascomicetos/química , Monitoramento Ambiental/métodos , Líquens/química , Oligoelementos/análise , Itália , Centrais Elétricas
4.
Environ Monit Assess ; 187(8): 500, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26160739

RESUMO

Thalli of the lichen Pseudevernia furfuracea were transplanted for 3 months (November 2010-January 2011) at 61 monitoring sites around a cement plant near Castrovillari (Calabria, southern Italy). NH3, NO x and SO2 concentrations were monitored monthly in a subarea of 10 sites (SA10) where the cement plant was located. At the end of the exposure period, the integrity of cell membranes; membrane lipid peroxidation (thiobarbituric acid reactive substances, TBARS level); vitality (cell respiration); chlorophyll a; chlorophyll b; carotenoids; phaeophytization quotient; photosynthetic efficiency and thalli concentrations of Al, Ca, Mg, V and Fe were measured. NO x concentrations correlated with the site distance from the cement plant while NH3 concentrations correlated with lichen vitality within SA10. For the monitoring area as a whole, only Fe and Mg concentrations correlated with membrane lipid peroxidation, while TBARS levels showed a significant increase and chlorophyll a, chlorophyll b and carotenoids a significant decrease with respect to the lichen origin area. Multivariate analysis (detrended correspondence analysis, cluster analysis and multi-response permutation procedure) of the eco-physiological parameters × monitoring sites data set resulted in four clusters termed C1, C2, C3 and C4. The eco-physiological parameters were compared among the four clusters and lichen origin area by one-way ANOVA. An index of environmental favourableness (IEF) to lichens was calculated to evaluate the spatial recovery of impaired values of TBARS, chlorophyll a, chlorophyll b, xanthophylls + carotenoids and phaeophytization quotient. The results indicate that there is no clear spatial trend in mycobiont impairment even though the IEF values suggest a higher number of sites with low levels of membrane lipid peroxidation in the 2--3-km distance band from the cement plant (the outermost) than in the two other distance bands (0-1 and 1-2 km). The photobiont seems to be damaged mainly in the inner distance band of the study area as suggested by the gradual but significant recovery trend of pigment levels and phaeophytization quotient from the inner distance band to the outer one (as shown by the IEF values). Conversion of chlorophyll to phaeophytin probably is not the only process affecting pigment levels.


Assuntos
Indústria da Construção , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Líquens/metabolismo , Adsorção , Amônia/análise , Amônia/metabolismo , Ascomicetos/fisiologia , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A , Itália , Líquens/efeitos dos fármacos , Líquens/fisiologia , Peroxidação de Lipídeos , Óxidos de Nitrogênio/análise , Óxidos de Nitrogênio/metabolismo , Fotossíntese , Estresse Fisiológico , Dióxido de Enxofre/análise , Dióxido de Enxofre/metabolismo
5.
Life Sci ; 87(9-10): 302-8, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-20637778

RESUMO

AIMS: Na(+), K(+)-ATPase activity contributes to the regulation of vascular contractility and it has been suggested that vascular Na(+), K(+)-ATPase activity may be altered during the progression of diabetes; however the mechanisms involved in the altered Na(+), K(+)-ATPase activity changes remain unclear. Thus, the aim of the present study was to evaluate ouabain-sensitive Na(+), K(+)-ATPase activity and the mechanism(s) responsible for any alterations on this activity in aortas from 1- and 4-week streptozotocin-pretreated (50 mg kg(-1), i.v.) rats. MAIN METHODS: Aortic rings were used to evaluate the relaxation induced by KCl (1-10mM) in the presence and absence of ouabain (0.1 mmol/L) as an index of ouabain-sensitive Na(+), K(+)-ATPase activity. Protein expression of COX-2 and p-PKC-betaII in aortas were also investigated. KEY FINDINGS: Ouabain-sensitive Na(+), K(+)-ATPase activity was unaltered following 1-week of streptozotocin administration, but was increased in the 4-week diabetic aorta (27%). Endothelium removal or nitric oxide synthase inhibition with l-NAME decreased ouabain-sensitive Na(+), K(+)-ATPase activity only in control aortas. In denuded aortic rings, indomethacin, NS-398, ridogrel or Gö-6976 normalized ouabain-sensitive Na(+), K(+)-ATPase activity in 4-week diabetic rats. In addition, COX-2 (51%) and p-PKC-betaII (59%) protein expression were increased in 4-week diabetic aortas compared to controls. SIGNIFICANCE: In conclusion, diabetes led to a time-dependent increase in ouabain-sensitive Na(+), K(+)-ATPase activity. The main mechanism involved in this activation is the release of TxA(2)/PGH(2) by COX-2 in smooth muscle cells, linked to activation of the PKC pathway.


Assuntos
Aorta Torácica/fisiopatologia , Diabetes Mellitus Experimental/fisiopatologia , Ouabaína/farmacologia , Prostaglandinas/metabolismo , Proteína Quinase C/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/enzimologia , Western Blotting , Ciclo-Oxigenase 2/biossíntese , Diabetes Mellitus Experimental/enzimologia , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Endotélio Vascular/fisiopatologia , Masculino , Prostaglandina H2/metabolismo , Ratos , Ratos Wistar , Tromboxano A2/metabolismo , Fatores de Tempo , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
6.
Environ Monit Assess ; 166(1-4): 125-37, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19479330

RESUMO

Changes in the benthic macroinvertebrate community in the Arente River (a tributary of the Crati river in the Region of Calabria, Italy) were monitored monthly for 1 year through stratified sampling by habitat (pools and riffles) together with general descriptors of communities structure and the extended biotic index (EBI) to assess the potential development of community alteration following strong hydrological increases. Results suggest that flow peaks and substratum instability remarkably affect population abundance and composition of macroinvertebrate assemblages in both macro-habitats whereas their ordination is due to chemical parameters analyzed only at low water periods. Organism and taxonomic densities as well as taxonomic richness all showed an appreciable reduction simultaneously with flow increases both in pools and riffles. Early colonizers (organisms with high dispersal and drifting tendency) dominate during hydrological perturbation and post-perturbation phases. Both EBI and environmental quality values more frequently show the development of river disturbance in pools than in riffles during and after flow changes. Regression analysis clearly shows that hydrological and substrate parameters are better predictors of community parameters changes (higher r(2) values) in pool habitats than in riffles habitats suggesting that depositional environments seem more suitable than erosive ones in monitoring macrobenthic community changes and, possibly, alterations due to hydrological variations.


Assuntos
Biodiversidade , Monitoramento Ambiental , Invertebrados/classificação , Rios/química , Movimentos da Água , Animais , Conservação dos Recursos Naturais , Ecossistema , Estações do Ano
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