1,721,359 research outputs found
Biomarkers as diagnostic and prognostic tools for wildlife risk assessment: Integrating endocrine-distrupting chemicals
No full textThe state of art of the biomarker approach in ecotoxicology is reviewed with particular reference to its use in the assessment of exposure to endocrine-disrupting chemicals in wildlife. The following topics are discussed: the theoretical basis of the biomarker approach; the advantages of biomarker strategies in biomonitoring programs; application of biomarker strategies in an ecotoxicological context; the main biomarker techniques; interpretation of the results; and the development and validation of nondestructive biomarkers
Biomarkers, strumenti di diagnosi e prognosi ambientale
No full textIn un' epoca sovraccarica di ambientalisti, ecologisti, naturalisti, verdi. . . ., dove la confusione su termini quali, ecologia, ambiente, inquinamento e contaminazione costituisce una consuetudine, l'esigenza di definire in maniera chiara e concisa Ie basi concettuali e metodologiche delle nuove discipline ecotossicologiche si presenta come un imperativo scientifico e morale per i veri "addetti ai lavori". Negli ultimi decenni l'ecotossicologia si e imposta, nell' ambito delle scienze ambientali, come la disciplina "guida" di un nuovo indirizzo scientifico e sociale basato suI concetto dello "sviluppo sostenibile". Viviamo in un'epoca che si "vanta" e si "avvale" della sintesi di migliaia di molecole di sintesi., devolute al miglioramento delle nostre condizioni di vita. E' nostro dovere, per noi e per Ie generazioni future, controllare e regolare la lara immissione e diffusione nella biosfera, per evitare, come in passato, il verificarsi di rilevanti danni ambientali. Negli ultimi decenni i biomarkers si sviluppano come un elemento innovativo nell' ambito delle indagini ecotossicologiche, rispondendo in maniera rapida e precisa ai quesiti basilari di questa disciplina come: quali sona gli effetti che i composti inquinanti provocano sulle popolazioni e/o comunità naturali? Ed ancora: come la valutazione di questi effetti può rappresentare un segnale precoce del livello di contaminazione ambientale? "Biomarkers: strumenti di diagnosi e prognosi ambientale" si presenta come il primo prezioso testo in lingua italiana, indirizzato ad un vasto pubblico di "addetti ai lavori" sulle tematiche del monitoraggio, protezione e salvaguardia ambientale. Questo volume presenta in maniera semplice e concisa le basi, teoriche, metodologiche ed applicative di questo innovativo strumento d'indagine ecotossicologica. Recentemente, sia a livello nazionale che comunitario, si è manifestata sempre più fortemente l'esigenza di introdurre queste metodologie a livello legislativo, come validi strumenti di controllo di "salute ambientale". In quest'ottica, la pubblicazione di un'opera che riassume le principali metodologie dei biomarkers, la chiave interpretativa dei risultati e le potenziali applicazioni nel campo del monitoraggio ambientale ed industriale, risulta d'enorme importanza per portare l'Italia al pari di altri paesi Europei e Nordamericani, fino ad oggi "leaders" in questo settore
The use of nondestructive biomarkers in the study of marine mammals
No full textMarine mammals have been subject to heavy anthropogenic pressure by direct killing and chemical pollution all over the world. Most studies of contamination and biomarker responses in marine mammals have been conducted using animals killed by hunting (out of a total of 12 cetacean species studied, 45% of the specimens were obtained by sacrificing the animal; out of a total of eight pinniped species studied, 40% of the specimens were obtained by killing). The development of a series of non-destructive techniques to evaluate biomarker responses and residue levels is recommended for the hazard assessment and conservation of endangered species of marine mammals. Here we review the current status of the non-destructive biomarker approach in marine mammals, describing the biological materials available for non-destructive tests in stranded (brain, liver, blood, skin, subcutaneous blubber, muscle and fur) and free-ranging animals (blood, skin biopsy, fur and faeces) and the respective biomarker techniques (mixed function oxidase activity and DNA damage in skin biopsy samples; porphyrins in faeces and fur; esterases, porphyrins, clinical biochemical parameter, vitamin A and micronuclei in blood samples). Residue analysis can be carried out in the various biological materials. We also report the results of applying this methodological approach to cetaceans (minke whale Balaenoptera acutorostrata, fin whale -Balaenoptera physalus, beluga whale - Delphinapterus leucas, short-finned pilot whale - Globicephala macrorhynchus, harbour porpoise - Phocoena phocoena, Risso's dolphin - Risso's Grampus griseus, Dall's porpoise - Phocoenoides dalli dalli, melon-headed whale - Peponocephala electra, bottlenose dolphin - Tursiops truncatus, striped dolphin - Stenella coeruleoalba, spinner dolphin - Stenella longirostris, killer whale - Orcinus orca) and pinnipeds (northern fur seal Callorhinus ursinus, hooded seal - Cystophora cristata, grey seal - Halichoerus grypus, harbour seal - Phoca vitulina, ringed seal - Phoca hispida, harp seal - Phoca groenlandica, ribbon seal - Phoca fasciata, largha seal Phoca largha, southern sea lion - Otaria flavescens) in field studies for prognostic and diagnostic purposes
Nondestructive biomarkers in ecotoxicology
No full textThe aim of this article is to attempt a concise review of the state of the art of the nondestructive biomarkers approach in vertebrates, establishing a consensus on the most useful and sensitive nondestructive biomarker techniques, and proposing research priorities for the development and validation of this promising methodology. The following topics are discussed: the advantages of the use of nondestructive strategies in biomonitoring programs and the research fields in which nondestructive biomarkers can be applied; the biological materials suitable for nondestructive biomarkers and residue analysis in vertebrates; which biomarkers lend themselves to noninvasive techniques; and the validation and implementation strategy of the nondestructive biomarker approach. Examples of applications of this methodology in the hazard assessment of endangered species are also presented
New tool to investigate toxicological hazard due to endocrine disruptors in mediterranenan cetaceans
No full textMediterranean cetaceans, particularly odontocetes, accumulate high concentrations of organochlorine contaminants (OCs) and are therefore exposed to high toxicological risk. Some OCs are known to be endocrine disrupting compounds (EDCs). The hypothesis that Mediterranean cetaceans (Stenella coeruleoalba, Delphinus delphis, Tursiops truncatus and Balaenoptera physalus) are subject to toxicological risk due to organochlorines and emerging contaminants, such as polybrominated diphenyl ethers (PBDEs) with endocrine disrupting
capacity, was investigated using non-lethal “diagnostic” and “prognostic” methods. CYP1A1 activity induction (Benzo(a)pyrene monooxygenase) in skin biopsies was used as a “diagnostic” indicator of exposure to organochlorines in odontocetes and mysticetes and in different populations of Stenella coeruleoalba. Marked differences in levels of OCs and CYP1A1 activity were found between fin whales and odontocetes. Organochlorine levels and CYP1A1 activity were significantly higher in the Stenella coeruleoalba population of the Mediterranean Whale Sanctuary than in those of two other study areas, suggesting that cetaceans are exposed to high risk in this protected area. Several questions remain still unanswered in ecotoxicological studies of Mediterranean cetaceans. The need for new biomarkers for EDCs and for a “cell model” to explore the different susceptibilities to several classes of ECDs, including emerging contaminants, led us to culture fibroblasts of different cetacean species as a non-lethal new investigation tool (“dolphins in test tubes”). As a new “prognostic” tool we explored interspecies and gender susceptibility to OC-EDCs and PBDEs using qualitative and semi-quantitative evaluation of target proteins, such as CYP1A1 and CYP 2B in cultured cetacean (Stenella coeruleoalba, Tursiops truncatus and Balaenoptera physalus) fibroblasts, by western blot, immunofluorescence technique and PCR real time. The information obtained in this pilot experiment will be the basis for further applications and validation of these methodologies to expolore different species and gender susceptibility of marine mammals to different mixtures of endocrine disrupting xenobiotics including emerging contaminants
Non lethal tools to assess the toxicological hazard of endocrine disruptor organochlorine contaminants in mediterranean cetaceans
No full textThe Mediterranean top predators, and particularly cetacean odontocetes, accumulate high concentrations of organochlorine contaminants (OCs), incurring high toxicological risk. Some organochlorine compounds, now with worldwide distribution, are known as endocrine disrupting chemicals (EDCs). Here the hypothesis that some Mediterranean cetaceans (Stenella coeruleoalba, Delphinus delphis, Tursiops truncatus and Balaenoptera physalus) are potentially at risk due to organochlorines with endocrine disrupting capacity is investigated. As “diagnostic” tool we use benzo(a)pyrene monooxygenase (CYP1A1) activity in marine mammal skin biopsies (non-lethal biomarker) as a potential indicator of exposure to organochlorines, with special reference to the compounds with endocrine disrupting capacity. A statistically significant correlation was found between BPMO activity and organochlorine EDs levels in skin biopsies of males of Balaenoptera physalus. A statistical correlation was also found between BPMO activity and DDT levels in skin biopsies of the endangered Mediterranean population of Delphinus delphis. As “prognostic” tool we propose the immunofluorescence technique in fibroblast cell cultures, for a qualitative and quantitative evaluation of the target proteins as CYP450 1A1-1A2, CYP450 2B4 and estrogen receptor (ER)
Seasonal variation of mixed-function oxidase activity in a population of Yellow-Legged herring gull: relationship to sexual cycle and pollutants
No full textInduction of the mixed-function oxidase (MFO) system has commonly been used as a biochemical marker of xenobiotic contamination in birds. The present study considers the influence of intrinsic (e.g. sexual cycle) and extrinsic (xenobiotic) factors in determining the levels of MFO activity in a population of Yellow-legged Herring gull (Larus cachinnans). Aldrin epoxidase undergoes marked seasonal variation, reaching a peak in the breeding season; on the other hand 7-ethoxyresorufin dealkylation activity is more closely related to certain organochlorine residues (polychlorinated biphenyls. Lindane, hexachlorobenzene). Seasonal variations in NADPH-and NADH-cytochrome c reductase and NADH-ferricyanide reductase activities were also found. These results suggest that seasonal variations in MFO activity, which may be related to the sexual cycle, need to be taken into account when considering biochemical effects of pollutants
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