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1.
Pateira de Fermentelos is a Cértima River enlargement, close to its river mouth (by the Agueda River), where the introduction of agricultural chemicals such as fertilisers and pesticides, domestic sewage, as well as heavy metals from electroplating industries, results in increased water pollution. The present research work concerns a 48 h in situ exposure of caged eels (Anguilla anguilla L.) at the Pateira de Fermentelos. Five exposure sites were selected, i.e., site A, site B, site C, site D and site E in order to study its water genotoxicity potential, measured in gill, blood, liver and kidney as DNA strand breaks. Eels were also exposed at a reference site by the Cértima River spring. Bottom water samples were collected for further physical-chemical analysis. Site A exposure, significantly decreased gill, blood and liver DNA integrity. Gill and liver DNA integrity was also significantly decreased at site B. At site C only blood DNA integrity was significantly decreased. The present field in situ study demonstrated that the three exposure sites close to the Pateira initial part, such as A, B and C are polluted by pro and/or genotoxic compounds. The genotoxic effects induced in A. anguilla L. suggest a different contamination of the exposure sites A, B and C, in genotoxic chemicals. Thus, according to its genotoxic potential the exposure sites A, B and C, may be ordered as follows site A>site B>site C. No genotoxic effects on A. anguilla L. were observed at site E as DNA strand breaks increase.  相似文献   

2.
This study assesses the antioxidant enzymes activities viz., catalase, glutathione peroxidase, glutathione S-transferase and nonenzymatic antioxidant molecule such as glutathione in Anguilla anguilla L. gill, kidney and liver in response to 8- and 48-h exposure to bleached kraft pulp mill effluent (BKPME). A. anguilla were caged and plunged at three different sites-50 (Site 1), 100 (Site 2) and 2000 m (Site 3) away from the closed BKPME outlet. A significant gill (8 and 48 h) and kidney (48 h) catalase activity decrease was observed at site 2 exposure whereas liver showed a significant increase in catalase activity after 8 and 48 h to site 1 exposure. Glutathione peroxidase (GPX) activity was significantly decreased in gill after 8-h exposure to site 1 and 48-h exposures to sites 1 and 2, respectively. Concerning gill, kidney and liver glutathione S-transferase (GST) activity, a significant gill GST activity decrease after 8 h at site 2 and 48 h at sites 1 and 2 was observed; in kidney, a significant decrease in its activity was observed after 48 h at sites 1 and 2, respectively, whereas in liver, the decrease was significant only at site 2 after 48-h exposure. The in situ BKPME exposure caused a significant total gill and kidney reduced glutathione (GSH) decrease after 8 h at site 2 exposure and after 48 h at site 1 and 2 exposures, respectively. However, a biphasic response was observed in liver, i.e. initial significant increase after 8 h at site 2 followed by a significant decrease after 48 h to the same site exposure. The enzymatic and nonenzymatic antioxidants pattern in gill and kidney, as observed in this study, was different than liver, demonstrating that the liver was more resistant to oxidative damage than gill and kidney. In addition, A. anguilla gill, kidney and liver antioxidants adaptation potentials may serve as a surrogate biomarker to BKPME exposure.  相似文献   

3.
Anguilla anguilla L. were exposed during 24 and 48 h to 2.7 muM beta-naphthoflavone (BNF), a known microsomal enzyme inducer. The BNF effects on thyroid-stimulating hormone (TSH), free triiodothyronine (T3), free thyroxine (T4) and cortisol plasma levels were investigated. Alterations on plasma glucose and lactate levels were also measured as an indication of energy-mobilizing hormones alterations. BNF showed to be able to decrease significantly A. anguilla plasma T4 levels, whereas TSH, T3 and cortisol plasma remained constant. However, plasma glucose levels were significantly increased, demonstrating that intermediary metabolism has been affected. These results demonstrate that BNF a PAH-like compound alters the normal functioning of the hypothalamo-pituitary-thyroid (HPT) axis in A. anguilla.  相似文献   

4.
Anguilla anguilla L. were exposed to 0, 0.1, 0.3, 0.9 and 2.7 microM abietic (AA), dehydroabietic (DHAA) acids and retene (Re) during 8, 16, 24 and 72 h. The eels plasma cortisol, glucose and lactate were measured. A significant decrease in plasma cortisol was observed at 72 h exposure to 0.9 and 2.7 microM Re. DHAA (0.1 microM) significantly decreased plasma cortisol in eels after 8 and 24 h exposure. However, a significant plasma cortisol increase was found after 16 h, 2.7 microM AA exposure and after 24 h exposure to 0.1 microM and 2.7 microM AA. Furthermore, 72 h exposure to 0.9 microM AA also induced a plasma cortisol increase. A general rise in plasma glucose was detected after all exposure periods to Re. The plasma lactate also increased after 72 h exposure to 2.7 microM AA and after 8 h exposure to 0.1 microM DHAA.  相似文献   

5.
The induction of liver ethoxyresorufin O-deethylase (EROD) activity was investigated in the European eel, Anguilla anguilla, collected from a Mediterranean brackish environment and experimentally exposed to benzo[a]pyrene (B[a]P) and beta-naphthoflavone (BNF). Eels were injected intraperitoneally at increasing doses (0.1, 1, 10, and 50 mg/kg wet body weight) using corn oil as a carrier and sacrificed after 7 days. The main objectives of the present study are: (1). to assess of the sensitivity of EROD induction as a biomarker to polycyclic aromatic hydrocarbon (PAH) exposure; (2). to determine an EROD dose-response relationship of the contaminants used; and (3). to compare the efficiency of B[a]P and BNF as inducers of EROD activity. Results showed that both chemicals resulted in a dose-dependent EROD induction, but increases were not linear. EROD activity seemed to reach a plateau at the exposure of 10 mg/kg in both treatment groups; B[a]P was a more potent inducer than BNF was at the higher doses (10 and 50 mg/kg), while the opposite result was observed at the lower ones (0.1 and 1 mg/kg). The greatest induction occurred in eels treated with 10 mg/kg B[a]P, in which a 261-fold increase in EROD activity was observed. Results showed that EROD activity in A. anguilla is significantly induced by B[a]P and BNF exposure, responding to a wide range of concentrations of these contaminants. We infer that this tool may be suited as a diagnostic biomarker for biomonitoring PAHs pollution in Mediterranean brackish environments and further field research is suggested.  相似文献   

6.
Anguilla anguilla L. ethoxyresorufin-O-deethylase (EROD) elevation by 2.7 microM beta-naphthoflavone (BNF) 3 days water exposure, or 4 mg/kg ip exposure, was studied in four different organs--liver, kidney, gills, and intestine. The results demonstrated a significant increase in liver EROD activity for the two previous conditions, whereas kidney EROD activity only increased during the intraperitoneal exposure. A. anguilla was also exposed during 8, 16, and 24 h to water contaminated with 2.7 microM BNF or benzo[a]pyrene (BaP) at 20 degrees C and 25 degrees C. Both compounds significantly increased liver EROD activity from 8 up to 24 h. There was no significant difference in liver EROD activity elevation by both compounds, either at 20 degrees C or 25 degrees C. Liver EROD activity was demonstrated to be one of the first warning systems concerning the presence of polycyclic aromatic hydrocarbons (PAHs) in water. A. anguilla 3 h exposure to diesel oil water-soluble fraction (DWSF) significantly increased plasma cortisol and significantly decreased plasma lactate. A prolonged exposure beyond 3 h, i.e. 4 h, 2, 3, 4, and 6 days to the previous conditions demonstrated a significant liver EROD activity elevation from Day 2 up to 6, and a significant increase in erythrocytic nuclear abnormalities (ENA) at Day 6.  相似文献   

7.
Several environmental pollutants, including metals, can induce oxidative stress. So, the objective of this study was to evaluate the effects of arsenic (As(III), as As(2)O(3)) on the antioxidant responses in the polychaete Laeonereis acuta. Worms were exposed to two environmentally relevant concentrations of As, including the highest previously allowed by Brazilian legislation (50 microg As/l). A control group was kept in saline water (10 per thousand) without added metal. It was observed that: (1) a peak concentration of lipid peroxide was registered after 2 days of exposure to 50 microg As/l (61+/-3.2 nmol CHP/g wet weight) compared to the control group (43+/-4.5 nmol CHP/g wet weight), together with a lowering of the activity of the antioxidant enzyme catalase (-47 and -48%, at 50 or 500 microg As/l respectively) and a higher superoxide dismutase activity (+305% at 50 microg As/l with respect to the control group); (2) a lower conjugation capacity through glutathione-S-transferase activity was observed after 7 days of exposure to 50 microg As/l (-48% compared to the control group); (3) a significant increase in As concentration was verified after 1 week of exposure to both As concentrations (50 and 500 microg/l); (4) worms exposed to As showed a limited accumulation of related methylated As species and the levels of non-toxic As species like arsenobetaine (AsB) and arsenocholine (AsC) remained unchanged during the exposure period when compared with the controls. Overall, it can be concluded that As interfered in the antioxidant defense system of L. acuta, even at low concentrations (50 microg/l) that Brazilian legislation previously considered safe. The fact that worms exposed to As showed high levels of methylated As species indicates the methylation capability of L. acuta, although the high levels of inorganic As suggest that not all the administered As(III) (as As(2)O(3)) is completely removed or biotransformed after 7 days of exposure.  相似文献   

8.
Giant reed (Arundo donax L.) was grown on surface soil and irrigated with mixed heavy metal solutions of Cd(II) and Ni(II) to study the impact of these heavy metals on its growth and photosynthesis. The tested concentrations were 5, 50, and 100 ppm for each heavy metal against the control and resulted in high cadmium and nickel (DTPA extractable) concentrations in the top zone of the pot soil. The examined parameters, namely, stem height and diameter, number of nodes, fresh and dry weight of leaves, and net photosynthesis (Pn) were not affected, indicating that plants tolerate the high concentrations of Cd and Ni. As giant reed plants are very promising energy plants, they can be cultivated in contaminated soils to provide biomass for energy production purposes.  相似文献   

9.
The data on the ecology of bilberry and cowberry in the West Siberian Plain, Kuznetsk Ala Tau, and highland Altai are presented. Ecological ranges of these plants and amplitudes of their tolerance for some environmental factors are described.  相似文献   

10.
Comparisons were made of metal concentrations in water and sediment with those in the muscle and livers of three species of fish caught in four seawater reservoirs (two in the Odiel estuary and two in the Bay of Cádiz). The concentrations of a large number of metals in the water, sediment and fish were higher in the Odiel reservoirs than in those in Cádiz. We found high metal-enrichment factors in the livers as compared to muscle (over 100 for Fe and Cu and around 5 for Zn, Ni, Cd and Pb). The three fish species showed differences in metal content. For example, eels accumulated more metals in muscle and grey mullet in the liver. The metal levels found in muscle in the three species were below the legal limits for human consumption, although Cu in the liver was above the limit in the three species taken from the Odiel reservoirs, and Zn levels in liver were over the maximum in eels from one of the Odiel marshes. Significant correlations (p<0.05) were obtained for the levels of numerous metals in water, sediment and fish.  相似文献   

11.
The environmental influence on Chernobyl-derived 137Cs levels in perch (Perca fluviatilis L.) and roach (Rutilus rutilus L.) was revealed using partial least-squares regression (PLS). The 53 environmental predictors used describe land use in catchment areas, various catchment area and lake characteristics, lake water chemistry, and fish stock composition. The study showed a profound effect of land use on the 137Cs levels in fish. Radiocaesium deposited on arable land was retained in the soil to a greater extent than was 137Cs deposited on wetlands, which more easily leached out to the lake ecosystems. The 137Cs deposition close to the lakes had a more pronounced effect on 137Cs levels in the fish than did more distant deposition. The radiocaesium bioavailability is mainly governed by lake water cation content, as hardwater lakes had significantly lower 137Cs content in fish. Resuspension of 137Cs contaminated sediments only had a limited influence on the observed levels in fish.  相似文献   

12.
Lead is still widely used in many industrial processes and is very persistent in the environment. Although toxic effects caused by occupational exposure to lead have been extensively studied, there are still conflicting results regarding its genotoxicity. In a previous pilot study we observed some genotoxic effects in a population of lead exposed workers. Thus, we extended our study analysing a larger population, increasing the number of genotoxicity endpoints, and including a set of 20 genetic polymorphisms related to lead toxicokinetics and DNA repair as susceptibility biomarkers. Our population comprised 148 workers from two Portuguese factories and 107 controls. The parameters analysed were: blood lead levels (BLL) and δ-aminolevulinic acid dehydratase (ALAD) activity as exposure biomarkers, and T-cell receptor (TCR) mutation assay, micronucleus (MN) test, comet assay and OGG1-modified comet assay as genotoxicity biomarkers. Lead exposed workers showed markedly higher BLL and lower ALAD activity than the controls, and significant increases of TCR mutation frequency (TCR-Mf), MN rate and DNA damage. Oxidative damage did not experience any significant alteration in the exposed population. Besides, significant influence was observed for VDR rs1544410 polymorphism on BLL; APE1 rs1130409 and LIG4 rs1805388 polymorphisms on TCR-Mf; MUTYH rs3219489, XRCC4 rs28360135 and LIG4 rs1805388 polymorphisms on comet assay parameter; and OGG1 rs1052133 and XRCC4 rs28360135 polymorphisms on oxidative damage. Our results showed genotoxic effects related to occupational lead exposure to levels under the Portuguese regulation limit of 70μg/dl. Moreover, a significant influence of polymorphisms in genes involved in DNA repair on genotoxicity biomarkers was observed.  相似文献   

13.
Experiments on daily exposure of gypsy moth larvae to heat stress have shown that it leads to an increase in the survival rate of larvae with reduced adaptation to artificial diet (AD) and a decrease in the survival rate of larvae well adapted to AD. It has been found that acetylcholine esterase and tyrosinase activities and the concentration of tyrosine derivatives are reduced significantly in stress-exposed larvae. The conclusion is drawn about a possible relationship between change in the level of larval adaptation to food and a switch in metabolism of tyrosine derivatives from hormone synthesis to melanin synthesis pathway.  相似文献   

14.
Immediate biomarker responses of two high-latitude populations of the blue mussel Mytilus edulis to benzo[a]pyrene (B[a]P) were evaluated. Mussels collected from a clean and a polluted site in southwest Iceland were exposed to the nominal dose of 100 microg B[a]P L(-l) for 3 h, after 4 days of acclimatization in clean seawater. To test the sensitivity to the toxicant and immediate biological responses, the following biomarkers were used: DNA single strand breaks, heart rate and feeding rate. All the biomarkers revealed differences between the study sites. Irrespective of the origin of the organisms, the short time exposure to the high B[a]P concentration did not induce DNA single strand breaks or significantly affect the feeding rate. However, the heart rate results showed significantly different responses. The mussels from the polluted site (Reykjavík harbour) increased their heart rate when exposed to B[a]P, while no difference was observed between the heart rate values of the individuals from the clean site (Hvassahraun). The mussels seem to sense the pollutant they have been previously exposed to, and their acute response indicates physiological adaptation to the polluted environment. The results indicate limited sensitivity and temporal predictivity, i.e. transient measurable changes of these biomarkers, as well as showing that the background of the organisms should be considered when evaluating short-term biomarker responses to contaminants.  相似文献   

15.
Previous studies investigating the exposure to metal(loid)s of populations living in the Panasqueira mine area of central Portugal found a higher internal dose of elements such as arsenic, chromium, lead, manganese, molybdenum and zinc in exposed individuals. The aims of the present study were to evaluate the extent of genotoxic damage caused by environmental and occupational exposure in individuals previously tested for metal(loid) levels in different biological matrices, and the possible modulating role of genetic polymorphisms involved in metabolism and DNA repair. T-cell receptor mutation assay, comet assay, micronucleus (MN) test and chromosomal aberrations (CA) were performed in a group of 122 subjects working in the Panasqueira mine or living in the same region. The modifying effect of polymorphisms in GSTA2, GSTM1, GSTP1, GSTT1, XRCC1, APEX1, MPG, MUTYH, OGG1, PARP1, PARP4, ERCC1, ERCC4, and ERCC5 genes was investigated. Significant increases in the frequency of all biomarkers investigated were found in exposed groups, however those environmentally exposed were generally higher. Significant influences of polymorphisms were observed for GSTM1 deletion and OGG1 rs1052133 on CA frequencies, APEX1 rs1130409 on DNA damage, ERCC1 rs3212986 on DNA damage and CA frequency, and ERCC4 rs1800067 on MN and CA frequencies. Our results show that the metal(loid) contamination in the Panasqueira mine area induced genotoxic damage both in individuals working in the mine or living in the area. The observed effects are closely associated to the internal exposure dose, and are more evident in susceptible genotypes. The urgent intervention of authorities is required to protect exposed populations.  相似文献   

16.
The biochemical response of wild sticklebacks collected in Autumn 2005 at seven stations in the North of France was studied using a set of complementary biomarkers. Here, data on biotransformation of xenobiotics, oxidative stress exposure and damages, neurotoxicity and endocrine disruption are provided. All the sites are characterized by a specific response pattern that allows distinguishing sampling locations. Moreover, these responses are in accordance with data on existing environmental pressures and the chemical analysis of metals performed in surface water. The assessment of individual responses is completed by fish population disturbance monitoring. Based on these measurements, the investigated sites are characterized by different levels of disturbance. This study argues for a multi-parametric approach of aquatic ecosystem contamination based on association between chemical, biochemical and ecological endpoints and provides a testimony of the usefulness of stickleback for this purpose.  相似文献   

17.
RationaleExposure to ambient particulate matter (PM) and ozone has been associated with cardiovascular disease (CVD). However, the mechanisms linking PM and ozone exposure to CVD remain poorly understood.ObjectiveThis study explored associations between short-term exposures to PM with a diameter < 2.5 μm (PM2.5) and ozone with plasma metabolite concentrations.Methods and resultsWe used cross-sectional data from a cardiac catheterization cohort at Duke University, North Carolina (NC), USA, accumulated between 2001 and 2007. Amino acids, acylcarnitines, ketones and total non-esterified fatty acid plasma concentrations were determined in fasting samples. Daily concentrations of PM2.5 and ozone were obtained from a Bayesian space-time hierarchical model, matched to each patient's residential address. Ten metabolites were selected for the analysis based on quality criteria and cluster analysis. Associations between metabolites and PM2.5 or ozone were analyzed using linear regression models adjusting for long-term trend and seasonality, calendar effects, meteorological parameters, and participant characteristics.We found delayed associations between PM2.5 or ozone and changes in metabolite levels of the glycine-ornithine-arginine metabolic axis and incomplete fatty acid oxidation associated with mitochondrial dysfunction. The strongest association was seen for an increase of 8.1 μg/m3 in PM2.5 with a lag of one day and decreased mean glycine concentrations (− 2.5% [95% confidence interval: − 3.8%; − 1.2%]).ConclusionsShort-term exposures to ambient PM2.5 and ozone is associated with changes in plasma concentrations of metabolites in a cohort of cardiac catheterization patients. Our findings might help to understand the link between air pollution and cardiovascular disease.  相似文献   

18.
Few multi-city studies in Asian developing countries have examined the acute health effects of ambient nitrogen dioxide (NO2). In the China Air Pollution and Health Effects Study (CAPES), we investigated the short-term association between NO2 and mortality in 17 Chinese cities. We applied two-stage Bayesian hierarchical models to obtain city-specific and national average estimates for NO2. In each city, we used Poisson regression models incorporating natural spline smoothing functions to adjust for long-term and seasonal trend of mortality, as well as other time-varying covariates. We examined the associations by age, gender and education status. We combined the individual-city estimates of the concentration–response curves to get an overall NO2–mortality association in China. The averaged daily concentrations of NO2 in the 17 Chinese cities ranged from 26 μg/m3 to 67 μg/m3. In the combined analysis, a 10-μg/m3 increase in two-day moving averaged NO2 was associated with a 1.63% [95% posterior interval (PI), 1.09 to 2.17], 1.80% (95% PI, 1.00 to 2.59) and 2.52% (95% PI, 1.44 to 3.59) increase of total, cardiovascular, and respiratory mortality, respectively. These associations remained significant after adjustment for ambient particles or sulfur dioxide (SO2). Older people appeared to be more vulnerable to NO2 exposure. The combined concentration–response curves indicated a linear association. Conclusively, this largest epidemiologic study of NO2 in Asian developing countries to date suggests that short-term exposure to NO2 is associated with increased mortality risk.  相似文献   

19.
20.
Russian Journal of Ecology - The proportion of jointly visited traps and the frequency of visits to the traps recorded during mark–recapture studies have been compared with the mathematical...  相似文献   

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