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1.
Ecotoxicology ; 32(3): 370-382, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36995475

RESUMO

Our research investigated the potential impacts of the fungicide Bordeaux mixture drift processes on off-target species representing terrestrial vegetation and fluvial-lacustrine zooplankton. The simulation of drift events was carried out by a predictive scaling analysis of the quantities potentially exported to a predetermined area adjacent to an agricultural field. The theoretical rate of deposition on a terrestrial species, the lichen Pseudevernia furfuracea, was calculated following high (4 kg ha-1) and low (2 kg ha-1) rate treatments using anti-drift nozzles and non-anti-drift nozzles. The experimental set up consisted in 40 boxes holding lichen thalli, all stored in a climatic chamber for 40 days. Spraying of the fungicide was alternated with rainfall simulations to reproduce scenarios related to agricultural practices. Following a single simulation, anti-drift nozzles resulted in a higher overall load deposited per unit of lichen surface area compared to non-anti-drift nozzles, although both loads significantly differed from controls. However, only anti-drift nozzles, associated with the high rate, caused a remarkable impairment of several ecophysiological parameters, differing (p < 0.05) from controls. Rainfalls promoted activation of lichen metabolism, mitigating the cell damage, but exported only 2.5% of the copper deposited on the thalli surfaces. Nevertheless, the exposure of Daphnia magna neonates to leachates showed significant outcomes for the two rates. After only 24 h, leachates resulting from the high application rate led to widespread mortality, which appeared to be extremely relevant after 48 h, whereas the lower rate induced much lower toxicity for both exposure times.


Assuntos
Fungicidas Industriais , Fungicidas Industriais/toxicidade , Cobre/toxicidade , Agricultura/métodos , Água Doce
2.
Environ Pollut ; 284: 117136, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915398

RESUMO

Spatial variation of the levels of polycyclic aromatic hydrocarbons (PAHs) was evaluated within an urban-industrial district where the main anthropogenic pressures are a 15 MW biomass power plant (BPP) and road traffic. The use of a high-density lichen transplant network and wind quantitative relationships made it possible to perform a hierarchical analysis of contamination. Combined uni-bi and multivariate statistical analyses of the resulting databases revealed a dual pattern. In its surroundings (local scale), the BPP affected the bioaccumulation of fluoranthene, pyrene and total PAHs, although a confounding effect of traffic (mostly petrol/gasoline engines) was evident. Spatial variation of the rate of diesel vehicles showed a significant association with that of acenaphthylene, acenaphthene, fluorene, anthracene and naphthalene. The series of high-speed wind values suggests that wind promotes diffusion rather than dispersion of the monitored PAHs. At the whole study area scale, the BPP was a source of acenaphthylene and acenaphthene, while diesel vehicles were a source of acenaphthylene. PAHs contamination strongly promotes oxidative stress (a threefold increase vs pre-exposure levels) in lichen transplants, suggesting a marked polluting effect of anthropogenic sources especially at the expense of the mycobiont. The proposed monitoring approach could improve the apportionment of the different contributions of point and linear anthropogenic sources of PAHs, mitigating the reciprocal biases affecting their spatial patterns.


Assuntos
Líquens , Hidrocarbonetos Policíclicos Aromáticos , Monitoramento Ambiental , Gasolina , Indústrias , Hidrocarbonetos Policíclicos Aromáticos/análise
3.
Environ Monit Assess ; 186(5): 3149-64, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24442534

RESUMO

This study investigated the temporal trends of element concentrations and ecophysiological parameters (integrity of cell membranes, membrane lipid peroxidation, and sample vitality) in thalli of the lichen Pseudevernia furfuracea transplanted in and around an industrial area of S Italy from May 2010 to May 2011, once every 3 months. Element accumulation at levels indicating that the atmosphere of the study area was polluted by most elements occurred only during the third trimester of exposure, and the ecophysiological parameter best reflecting this trend was sample vitality expressed in terms of activity of the enzyme dehydrogenase. Among the available climatological parameters, the different amount of rainfall during the exposure period may influence the results, especially the number of hours with rainfall >16 mm/day, which is the threshold between light-moderate and moderate-heavy rainfall in the Mediterranean area.


Assuntos
Poluentes Atmosféricos/análise , Ascomicetos/química , Monitoramento Ambiental/métodos , Líquens/química , Oligoelementos/análise , Poluição do Ar/estatística & dados numéricos , Indústrias , Itália , Líquens/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos
4.
Environ Monit Assess ; 146(1-3): 453-71, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18161027

RESUMO

To address the problem of whether hydrographic basins of southern Italian regions such as Calabria are exposed to "ecological stability pressures," we here provide the first results of four chemical and biological (macroinvertebrates) monitoring activities. The data accumulated within four hydrographic basins between May and November of 2002, November of 2005 and May of 2006 showed that about 1/3 of the macrobenthos sampled among a total of 14 rivers in the northern-central part of Calabria region provided optimal environmental quality values of Extended Biotic Index (E.B.I.), 1/3 denoted a slight impairment and the remaining samples exhibited very strong environmental alterations. It is interesting to note that E.B.I. is directly correlated with the taxonomic richness plus abundance, and inversely with the dominating taxon. This suggests that high environmental quality values are rather positively correlated with spatial heterogeneity and taxa eveness. In addition, the more compromised stations were located on plain segments where anthropization is reported to be at its highest level and there the macrobenthic communities seem to be made up of mostly potamon type of taxa with a high abundance of collector euriecious organisms while better quality stations, mostly located at high altitude, are characterized by a considerable presence of E.P.T. taxa. Chemical parameters did not result to be substantially altered underling that the hydrologic and geomorphological alterations may play a primary role in the control of macrobenthic communities and environmental quality. Overall the above results suggest that E.B.I. variations seem to be highly coherent with changes of main biodiversity parameters and their joined application is an efficient tool for detecting ecological state alterations of lotic environments.


Assuntos
Monitoramento Ambiental/métodos , Rios/química , Itália
5.
Adv Exp Med Biol ; 266: 121-33, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2486145

RESUMO

The most important products of the combustion process are SO2, NOx, CO2 and the heavy metals. When these substances come into contact with the biotic components of the ecosystems they produce an oxidative damage by means of a free radical mechanism. One of the significant natural sources of these oxides and metals are the volcanic emissions that contribute, either locally or more diffusely, to enrich the atmosphere with these substances. The area of Campi Flegrei (Naples, Italy) is an experimental model fit for studying the contemporary effect of the aforesaid oxidative agents, because it is characterized by a continuous fumarolic activity, particularly in the area of the widest crater (Solfatara). We have made so two experiments utilizing rats and earthworms (Octolasium complanatum) to evaluate the following aspects in phylogenetically very different organisms: 1. the combined effect of the atmospheric pollutants, 2. the effect of the only heavy metals (Cu, Ni, Mn), 3. the protection action played by reduced glutathione in rats. The reduced glutathione being either a substrate of the glutathione proxidase or an oxyradicals scavenger, is one of the main protection agents against the above stress. Because many papers suggest that the mentioned atmospheric pollutants damage both animal and vegetable organisms by their oxidative properties, the reduced glutathione seems to be able to counteract efficaciously the damaging activity studied in terms of age pigments production.


Assuntos
Poluentes Atmosféricos/toxicidade , Ceroide/biossíntese , Glutationa/farmacologia , Animais , Desastres , Feminino , Radicais Livres , Gânglios Espinais/efeitos dos fármacos , Itália , Lipofuscina/biossíntese , Masculino , Oligoquetos , Oxirredução , Ratos , Ratos Endogâmicos , Especificidade da Espécie , Tiobarbitúricos
6.
Adv Exp Med Biol ; 266: 135-41; discussion 141-2, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2486146

RESUMO

The effect of the exposure of Torpedo marmorata to a single dose of 400 cGy of ionizing radiation and doses of 200 cGy/week for 4 weeks has been studied. The parameters measured were the TBA reactivity and lipofuscin production, a fluorescent pigment that is thought to derive from the reaction of malonaldehyde, a peroxide-degradation product, with free amino-groups. Acute irradiation was found to generate an increase of peroxidative damage in some tissues. This effect was inhibited by acetyl homocysteine-thiolactone, a drug that increases the activity of tissue superoxide dismutase. Chronic irradiation produces a severe increase in the generation of lipofuscin.


Assuntos
Ceroide/biossíntese , Radiação Ionizante , Animais , Feminino , Sequestradores de Radicais Livres , Lipofuscina/biossíntese , Masculino , Tiobarbitúricos , Tiofenos/farmacologia , Torpedo
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