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The use of protozoa in ecotoxicology: Application of multiple endpoint tests of the ciliate E. crassus for the evaluation of sediment quality in coastal marine ecosystems.
No full textThe use of multiple endpoints to assess cellular responses to environmental contaminants in the interstitial marine ciliate Euplotes crassus
No full textThis paper presents the results of investigations on the suitability of Euplotes crassus, an interstitial marine ciliate, to be used as model organism in ecotoxicology and thereafter to evaluate the toxicity of estuarine and coastal sediments upon laboratory exposure. Nowadays, anthropogenic activities have resulted in accumulation of metals and organic pollutants in the environment as well as in the food chain hence leading to serious ecological and human health problems. This may pose a risk to benthic and epibenthic organisms and it is crucial to discover toxicity tests that will identify adverse effects of sediment-associated chemicals on benthic organisms. Due to their nature as a eukaryotic cell/organism and their position in the food web, ciliated protozoa are suitable models for evaluating the effects of pollution on aquatic communities. Lethal and sublethal effects of exposure to inorganic and organic pollutants were tested on the cell mortality, replication rate, lysosomal membrane stability and endocytosis rate of E. crassus. Increasing nominal concentrations of individual and mixtures of mercury, copper, and benzo(a)pyrene were investigated in this study as they might be bioavailable in naturally occurring polluted sites. A significant decrease in the mean replication rate (p<0.05) was found after 24h exposures to m/μM concentrations of all tested pollutants. At the same time, significant decreases of lysosomal membrane stability (p<0.05) were observed for Cu (5 μM), Hg (10 nM), and B(a)P (200 nM). Among the entire suite of tests, endocytosis rate test demonstrated the highest sensitivity. Exposures to binary mixtures of all studied pollutants were performed showing both inorganic-organic and inorganic-inorganic additive and/or antagonist effects. Moreover, medium salinity was also varied to mimic estuarine-like environmental conditions linking biological response to ionic strengths. Under these conditions significant increases of both endocytosis rate and lysosomal membrane stability were observed and related to the increment of some Hg- and Cu-related toxic complexes. The studied biomarkers were always able to discriminate between the effects of organic and inorganic pollutants. Together with the short time and simplicity of the test procedures, results obtained in this study indicate that E. crassus is a promising and convenient bioindicator for evaluating the toxicity of different environmental matrixes like pore water, sediments and wastewaters--polluted by metals and organic pollutants
Mixed function oxidases as an index of environmental pollution: a multi-trophic level approach
No full textEthoxyresorufin O-deethylas (EROD) activity and fluctuating asymmetry (FA) in Zosterisessor ophiocephalus (Teleostei, Gobiidae) as indicators of environmental stress in the Venice Lagoon
No full textSequential toxicity identification evaluation (TIE) for the characterizing toxicity of Venice Lagoon sediment: Comparison of two different appraches.
Full text linkhttp://dx.medra.org/10,1016/j.ecoenv.2008.06.01
Valutazione dell'impatto ambientale legato alle attività di estrazione di idrocarburi gassosi nel mare Adriatico: risultati preliminari del monitoraggio delle piattaforme Clara Nord e Clara Est, ENI S.p.A
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First attemps in evaluating the effects of hydraulic dredging on the target species Chamelea gallina: biochemical and behavioural responses
No full textUse of multiple cell and tissue-level biomarkers in mussels collected along two gas fields in the northern Adriatic Sea as a tool for long term environmental monitoring
No full textBiochemical and behavioural effects of hydraulic dredging on the target species Chamelea gallina
No full textThis study is focused on evaluating biological effects on the target species Chamelea gallina as a result of repeated
exploitation of clam beds by hydraulic dredging. A biomarker approach was adopted and two physiological indices were
applied: adenylate energy charge (AEC) (biochemical level) and reburrowing behaviour (organism level). The aim was to
investigate the biological response to various types of fishing, i.e., commercial systems using water at high pressures (HP),
and experimental systems at lower pressures (LP) in the field, and to evaluate the response of clams to mechanical stress
in the laboratory. Field results showed that HP-treated clams exhibited significantly lower levels of AEC compared with
LP treatments. A similar trend was shown by reburrowing behaviour; HP-treated clams reburrowed less. Laboratory results
were less clear: a very low level of AEC was measured in both control and treated clams. These poor conditions in foot
muscle did not indicate worsening at organism level, as no dead or dying clams were recorded throughout the experiment.
However, repeated mechanical stress reduced the percentage of reburrowing clams, which suggested that harvesting may
affect reburrowing behaviour
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