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1.
Long term effects of sublethal concentrations of oil on the marine environment have become of general concern. Cytochrome P4501A activity (EROD) in liver and fixed wavelength fluorescence detection of PAHs metabolites (FF) have in this study been used as biomarkers for dispersed oil exposure on a long term period of juvenile turbot (Scophthalmus maximus L.). A Continuous Flow System was used to carry out the study. The fish were continuously exposed to 0.125, 0.5 or 2.0 mg litre−1 dispersed topped crude oil for 6, 15, 24 h, 4 and 21 days followed by a 9 days recovery period in clean seawater. No induction of the cytochrome P4501A was measured. A maximum level in bile metabolites (4- to 5-fold) was recorded after 24 h of exposure revealing thereby a detoxification process, but a decline occurred from day 4 to day 21. This study demonstrated that FF detection of PAHs metabolites in bile could be a more sensitive biomarker than EROD activity in a long term exposure to sublethal concentration of oil.  相似文献   

2.
Induction of cytochrome P4501A in fish is a well-known indicator of exposure to polycyclic aromatic hydrocarbons (PAHs) and determination of PAH metabolites in bile by fixed wavelength fluorescence (FF) or synchronous fluorescence spectroscopy (SFS), has become an useful method in monitoring programs. In this work the relationship between cytochrome P4501A (EROD activity) and levels of biliary PAH metabolites was measured in the European eel Anguilla anguilla, in both field and laboratory conditions: organisms were sampled on a seasonal basis from the Orbetello lagoon (Tuscany) to characterize the natural variability of these biological parameters, while in laboratory eels were intraperitoneally injected with benzo[a]pyrene to investigate temporal and dose-dependent induction patterns. Results showed that induction of cytochrome P450 and accumulation of PAHs metabolites in bile are not necessarily correlated either in field, or in laboratory investigations; different seasonal changes were measured in natural conditions and slight variations in dose and time response patterns were also obtained in laboratory exposures.  相似文献   

3.
Juvenile turbot (Scophthalmus maximus) were exposed to benzo(a)pyrene (BaP) for 14 d using a glass bead generator flow-through system. Exposure was followed by a recovery period of 16 d. The highest BaP concentration in the edible portion of the fish, 16.5 ± 4.3 μg BaP/kg, was observed on the first day. Then concentrations dropped following first-order kinetics. BaP was below detection level at the end of the experiment. A statistically significant increase in bile fluorescence was observed from day 9 until the end of the experiment, suggesting the elimination of BaP metabolites by this route. No significant differences between control and exposed fish in EROD activity and CYP1A concentration, measured by immunodetection method, were observed. Intraperitoneal injection of 2.5 mg BaP/kg in juvenile turbot induced EROD activity. Under waterborne experimental conditions, bile fluorescence was observed to be a more sensitive biomarker of BaP exposure than EROD activity and CYP1A measurement.  相似文献   

4.
Juvenile turbot (Scophthalmus maximus) were injected intraperitoneally with either corn oil or 5 mg/kg benzo[a]pyrene (BaP) dissolved in corn oil and sampled I and 3 days after injection. After 1 day, no elevation of 7-ethoxyresorufin O-deethylase (EROD) activity was observed, however bile metabolites (BaP-7,8 dihydrodiol representing 70% of the total metabolites) and a single hepatic DNA adduct spot (0.47 adducts/10(8) nucleotides) identified by 32P-postlabelling were formed. No BaP metabolites or DNA adducts were observed in either control or carrier control fish. Fish sampled after 3 days reported 5-fold higher (P < 0.05) levels of EROD activity, a shift in the bile metabolite profile towards BaP phenol formation (1OH and 30H BaP comprising up to 60% of total metabolites detected) and the formation of two adduct spots (0.86 and 0.71 adducts/10(8) nucleotides). These results show that BaP can be metabolised and form hydrophobic DNA adducts in turbot without EROD elevation. Following EROD elevation, a shift in the profile of both BaP metabolites and BaP metabolite-DNA interactions occurs indicative of other oxidative processes.  相似文献   

5.
Effects on the hepatic cytochrome P450 1A1 system were investigated in juvenile rainbow trout i.p. injected with three different aromatic containing fractions: kerosene, light gas oil or heavy gas oil, originated from distilled North Sea crude oil. Kerosene treatment resulted in no effect on the P450 1A1 system, light gas oil injection caused a weak induction of EROD activities and heavy gas oil treatment resulted in a prominent induction of EROD activities as well as accumulation of CYP1A1 mRNA and P450 1A1 protein levels. The effects of heavy gas oil were compared with effects of β-napthoflavone (β-NF) on the P450 1A1 system. It was obvious that important discrepancies seemed to exist between EROD activities and corresponding CYP1A1 mRNA and P450 1A1 levels in rainbow trout treated with either heavy gas oil or β-NF i.e. heavy gas oil treatment resulted in higher specific EROD activities (EROD/P450 1A1) compared to β-NF. GC-MS analyses revealed that liver and bile from heavy gas oil treated rainbow trout in addition to naphthalene also contained polycyclic aromatic hydrocarbons such as phenanthrenes, anthracene, pyrenes, fluoranthene benz(a)anthracene and chrysene, while none of these compounds were detected in control trout.  相似文献   

6.
Induction of cytochrome P4501A in fish is a well-known indicator of exposure to polycyclic aromatic hydrocarbons (PAHs) and determination of PAH metabolites in bile by fixed wavelength fluorescence (FF) or synchronous fluorescence spectroscopy (SFS), has become an useful method in monitoring programs. In this work the relationship between cytochrome P4501A (EROD activity) and levels of biliary PAH metabolites was measured in the European eel Anguilla anguilla, in both field and laboratory conditions: organisms were sampled on a seasonal basis from the Orbetello lagoon (Tuscany) to characterize the natural variability of these biological parameters, while in laboratory eels were intraperitoneally injected with benzo[a]pyrene to investigate temporal and dose-dependent induction patterns. Results showed that induction of cytochrome P450 and accumulation of PAHs metabolites in bile are not necessarily correlated either in field, or in laboratory investigations; different seasonal changes were measured in natural conditions and slight variations in dose and time response patterns were also obtained in laboratory exposures.  相似文献   

7.
Pollutants such polycyclic aromatic hydrocarbons (PAHs) are released into the environment by urban communities and industries and the enzymes that catalyse the biotransformation of pollutants play a key role regarding the accumulation of these compounds in fish species inhabiting these areas. In this study the relationship between phase I (EROD activity) and phase II (GST activity) and PAH metabolites was measured in grey mullet (Mugil cephalus) after capture in the Douro estuary, and after long-term depuration in an unpolluted laboratory environment. The results showed a significant decrease in EROD activity after 1 month and in bile metabolites after 4 months in captivity, with both maintaining reduced levels at 4 and 8 months depuration. Liver GST activity did not showed significant changes. This study provides evidence that Douro estuary waters contain bioavailable PAHs that can be associated with the induction of cytochrome P450, and that mullets have the ability to metabolise and eliminate PAHs.  相似文献   

8.
In fish, as well as in mammals, it is well known that the cytochrome P450-dependent oxidative metabolism of xenobiotics can generate DNA-reactive species. Moreover, this metabolism is known to be inducible by several compounds of environmental significance, such as polychlorobiphenyls, polycyclic aromatic hydrocarbons (PAHs) and dioxins. Consequently, we studied the relationship between the degree of induction of the cytochrome P4501A, expressed as that of 7-ethylresorufin O-deethylase (EROD) activity, and the level of DNA-adducts, using the post-labelling assay, in the liver of rainbow trout exposed to benzo(a)pyrene (a representative PAH). The results showed a significant 2- to 4-fold increase in EROD activity 2, 4 and 8 days after treatment, paralleled by an increase in DNA-adduct levels. This work further emphasizes the involvement of cytochrome P4501A in the metabolism of benzo(a)pyrene into genotoxic metabolites in rainbow trout.  相似文献   

9.
Polycyclic aromatic hydrocarbons (PAHs) pollution, particularly in coastal environments, is a global concern. In this study, the biomonitoring and ranking effects of PAHs in the rockfish Sebastiscus marmoratus were determined in the Maowei Sea, China. The results showed that the concentrations of the 16 priority PAHs detected in the surface seawater were moderate compared with those in other coastal areas worldwide, and the possible sources were rapid industrialization and urbanization combined with atmospheric deposition and runoff. Nested analysis of variance (ANOVA) suggested significant differences in the hepatic ethoxyresorufin-O-deethylase (EROD) activities and phenanthrene-derived metabolites in bile between the port area and the oyster farming area. The fish expert system (FES) was applied to evaluate the biological effects of PAHs on fish. The FES data demonstrated that the biological effect levels of Site S1 (level III, medium stress) were higher than those of the other sampling sites (level II, low stress).  相似文献   

10.
The in vivo response of freshwater fish exposed to pollutants was assessed using two biomarkers, 7-ethoxyresorufin-O-deethylase (EROD) induction and DNA single strand breaks. Chub (Leuciscus cephalus) were caught in spring and in fall at various locations in the river Rhône watershed. EROD activity was measured in the liver while DNA damage was evaluated in chub erythrocytes using the recently developed Comet assay. Chemical contamination was evaluated both in fish muscle (PCBs) and in sediment (PCBs, PAHs, heavy metals) collected at each sampling station. Sex of individuals was shown to influence the level of EROD activity but not the level of DNA damage. The EROD activity as well as the DNA damage were found to be higher in the mostly contaminated stations compared to the reference one. This study shows that multibiomarker-based approach provides complementary informations about early effects in feral fish exposed to complex chemical pollution and highlights the interest of the Comet assay in genotoxicity assessment.  相似文献   

11.
INTRODUCTIONNumeroustinybacteriaareextensivelydistributedinthesea .Theydecomposeabundantorganizmandplanktondetritus ,transformingthemintoinorganicmaterialsintheseawater .Thebacteriautilizeddissolvableorganiccarbon (DOC) ;theprotozoanatethebacteria .AndtheD…  相似文献   

12.
长江冲淡水区细菌生产力研究   总被引:11,自引:3,他引:11  
为了解细菌在长江口冲淡水区生态系营养动力学过程中的重要作用,笔者于1997年10月10日至20日,1998年5月14日至6月1日在观测海区以及在绿华山海域设置大水体围隔生态系实验装置进行细菌生产力的现场观测研究.结果表明,秋季观测海区平均细菌生产力(C)为(1.44±1.30)μg/(dm3·h),高值出现在测区中部的A3,B3和C3站.春季测区表层细菌生产力(2.43±1.22)μg/(dm3·h)高于底层(1.01±0.43)μg/(dm3·h),高值出现在测区中部的A3和B断面诸站.秋、春季平均细菌生产力相当于浮游植物初级生产力的23%.秋季和春季表层细菌数量分别为(5.22×108±0.88×108)个/dm3和(1.97×108±1.10×108)个/dm3.1998年5月18日至6月1日在围隔实验点的自然海区中细菌生产力变幅范围为0.13~5.79μg/(dm3·h),平均值为(2.47±1.60)μg/(dm3·h).围隔装置内加可溶性磷(PO43-)实验,春季细菌生产力由1.28μg/(dm3·h)增长至32.20μg/(dm3·h),其增长幅度低于秋季1.43~43.47μg/(dm3·h).油污染实验中细菌生产力由6.61μg/(dm3·h)增长至37.97μg/(dm3·h),呈逐日上升趋势.  相似文献   

13.
为了解和探讨3~5环PAHs对海水鱼类胚胎发育的毒性及作用方式,比较研究了菲(phenanthrene,Phe)、芘(pyrene,Py)、苯并(a)芘(benzo(a)pyrene,BaP)单一暴露和三者各自与α-萘黄酮(α-naphthoflavone,ANF)联合暴露对海水青鳉(marine medaka, Oryzias melastigma)胚胎发育的毒性效应。胚胎体内EROD活性、发育畸形、孵化率和心律等毒性指标被测定,结果显示:Phe,Py和BaP对海水青鳉胚胎体内EROD活性的诱导能力大小为BaP>Py>Phe,各化合物对EROD诱导与发育畸形之间的关系较为复杂,除Phe所引起的EROD诱导与畸形指数之间呈显著相关(r=0.95,p=0.015)外,Py和BaP均无相关性;在100 μg/dm3 ANF影响下,CYP1A活性诱导被抑制,但胚胎发育的畸形指数被显著提高,ANF分别与Phe,Py和BaP的联合暴露对胚胎发育呈潜在的协同作用。本文研究初步表明,3~5环PAHs化合物对海水青鳉胚胎发育的毒性作用方式可能不同;CYP1A活性抑制在PAHs混合物对海水青鳉胚胎发育的毒性作用过程中未起到缓解毒性的作用,CYP1A抑制剂与PAH型CYP1A诱导剂的混合物对鱼类胚胎发育具有潜在的协同毒性作用,现有的PAHs混合物毒性风险评价方法可能低估了实际环境中PAHs的风险;海水青鳉早期生活阶段的心脏发育对PAHs混合物暴露较为敏感,可推荐其作为生物标志物指示PAHs或溢油污染。  相似文献   

14.
海水养殖污染区鱼肝EROD酶活力分析   总被引:3,自引:0,他引:3  
顾海峰 《台湾海峡》2002,21(3):292-295
对马銮湾和宝珠屿海域网箱养殖的美国红鱼 (Sciaenopsocellatus)肝脏微粒体EROD酶活性测定发现 ,马銮湾样品中的EROD酶活性 [0 .0 0 2 1U/(mg·蛋白质 ) ]大大低于宝珠屿海域样品EROD酶活性 [0 .0 0 63U/(mg·蛋白质 ) ],表明马銮湾水体受多环芳烃 (PAHs)的污染比宝珠屿海域受PAHs污染更轻微 .  相似文献   

15.
This study describes the spatial variation and the duration of the impacts from the Hebei Spirit oil spill using specific biochemical indices in resident benthic fish. Enzymatic activities and biliary PAHs metabolites were higher at the site closer to the spill area in four months after spill incident. Regarding our results of detoxification response, markers of Phase I followed a similar trend in accordance with levels of biliary metabolites, while markers of phase II and GST appeared relatively unchanged.  相似文献   

16.
以褐菖鲉为实验鱼类,以其鳃丝EROD为研究对象,进行了室内鳃丝EROD活性测定方法条件的摸索和现场海域石油类污染监测的初步应用研究.室内EROD活性测定条件摸索实验结果表明:褐菖鲉鳃丝EROD活性测定的最适pH值为7.8、最适温度为35℃、最适鳃丝用量为18.8±1.9 mm;在鳃丝总长相近(约20 mm)的条件下,剪切成2 mm长的鳃丝片段与否对于EROD活性无显著差异;反应50 min内EROD具有较高活性,随后呈现下降趋势.2次厦门西海域污染现场监测结果表明:褐菖鲉鳃丝EROD活性与海水石油类含量具有良好的正相关趋势,与对照组比较总体上具有显著的差异.因此,褐菖鲉鳃丝的EROD活性测定方法与褐菖鲉肝的一样,能够作为生物标志物应用于现场海区的石油类污染及其生化效应的监测.  相似文献   

17.
The performance of a lab-scale flow-through exposure system designed for the evaluation of ecotoxicity due to oil spills was evaluated. The system simulates a spill event using an oil-coated gravel column through which filtered seawater is passed and flows into an aquarium containing fish embryos of olive flounder (Paralichthys olivaceus) and spotted sea bass (Lateolabrax maculates). The dissolved concentrations of individual polycyclic aromatic hydrocarbons (PAHs) in the column effluent were monitored and compared with theoretical solubilities predicted by Raoult’s law. The effluent concentrations after 24 and 48 h were close to the theoretical predictions for the higher molecular weight PAHs, whereas the measured values for the lower molecular weight PAHs were lower than predicted. The ratios of the concentration of PAHs in flounder embryos to that in seawater were close to the lipid-water partition coefficients for the less hydrophobic PAHs, showing that equilibrium was attained between embryos and water. On the other hand, 48 h were insufficient to attain phase equilibrium for the more hydrophobic PAHs, indicating that the concentration in fish embryos may be lower than expected by equilibrium assumption. The results indicate that the equilibrium approach may be suitable for less hydrophobic PAHs, whereas it might overestimate the effects of more hydrophobic PAHs after oil spills because phase equilibrium in an oil-seawater-biota system is unlikely to be achieved. The ecotoxicological endpoints that were affected within a few days are likely to be influenced mainly by moderately hydrophobic components such as 3-ring PAHs.  相似文献   

18.
Newark Bay (NB) killifish (Fundulus heteroclitus) have been chronically exposed to environmental contaminants that activate the aryl hydrocarbon receptor (AHR) and are tolerant to toxic effects and CYP1A induction provoked by AHR ligands. Resistance to CYP1A induction could be due to an epigenetic mechanism such as DNA methylation. We measured in-ovo CYP1A catalytic activity (ethoxyresorufin-O-deethylase, EROD) in NB and reference site killifish embryos aqueously exposed to various concentrations of the de-methylating agent 5-azacytidine, 5-AC (5, 50 and 500 μ(micro)M) with or without 0.2 μ(micro)g/l of the CYP1A inducer 3,3,4,4,5 pentachlorobiphenyl (IUPAC PCB126). Neither PCB126 alone, nor PCB126 plus 5-AC, induced EROD above levels in vehicle treated Newark Bay fish. In reference site fish, the same PCB126 dose provoked a 7.4-fold EROD induction relative to controls. We conclude that Newark Bay killifish are resistant to CYP1A induction by co-planar PCBs during early embryological development and our data suggests that DNA methylation does not play a critical role in resistance to CYP1A induction in this model.  相似文献   

19.
Dioxin-like compounds (DLC) induce toxic responses in early life stages of fish through activation of the aryl hydrocarbon receptor (AhR) which is frequently assessed by ethoxyresorufin-O-deethylase (EROD) activity. A novel spectrofluorimetric method was developed to quantitatively assess EROD activity in individual living embryos and prolarvae of a marine model fish species, the mummichog Fundulus heteroclitus. This in vivo method is based on the measurement of the production of resorufin by single live embryos or prolarvae after 5 h incubation with ethoxyresorufin. Freshly fertilized eggs were treated topically from 2.5 to 50 pg egg−1, with 3,3′,4,4′,5-pentachlorobiphenyl (PCB126), a prototypical DLC. EROD activity was assessed in embryos (7 days post-fertilization) and prolarvae (16 days post-fertilization). Resorufin was measured both in the culture medium (25‰ seawater) and in whole fish homogenates, to assess the percentage retained in the body. Approximately 95% and 17% of the resorufin produced in vivo was retained in embryos and prolarvae respectively. EROD activity in homogenates of embryos and in the culture medium of prolarvae increased linearly with dose. EROD activity measured by the in vivo method was highly correlated to that measured by a traditional in vitro technique using S9 fractions for both embryos and prolarvae. Both in vivo and in vitro EROD activity were higher in prolarvae than in embryos pretreated with PCB126. EROD induction measured in prolarvae by the in vivo and in vitro methods were similar whereas higher induction was measured in vivo than in vitro in embryos. The in vivo method was more sensitive and as reliable as the in vitro technique, and required a lower number of fish (4 compared to 3 pools of 5). This in vivo method is useful to link EROD induction in individual embryos or prolarvae to other organism-level responses. Further studies with other categories of xenobiotics should be performed to assess potential toxic effects on resorufin absorption/excretion processes which could affect in vivo measurements.  相似文献   

20.
The objective of these studies was to characterize hepatic Cyp1A induction by complex carbonaceous pitches both in Japanese medaka exposed via aquarium water and in cultured fish liver cells. Carbonaceous pitches were extracted with DMSO and added to aquaria water of medaka or to cultured medaka or trout liver cells, and CyplA induction was assessed by EROD assay. When medaka were exposed to different carbonaceous pitches, EROD activity was induced to different extents, and increased EROD induction was associated with increasing temperature of hydrogenation. EROD induction in cultured fish liver cells was somewhat less sensitive than that observed in vivo. These studies indicate CyplA induction in medaka can be used to detect compounds, such as polyaromatic hydrocarbons, in complex samples and could be used as a biomarker for the presence of these compounds in the environment.  相似文献   

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