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1.
Freshwater fish Cyprinus carpio have been exposed to sublethal concentrations of fenvalerate (0.010 ppm) and cypermethrin (0.020 ppm) for 6, 12, 24 and 48 hours. After each exposure period, certain blood parameters were studied. A decrease in red blood corpuscular (RBC) count, haemoglobin (Hb) concentration, packed cell volume (PCV) and mean corpuscular haemoglobin concentration (MCHC), on the one hand, and an increase in mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH), on the other hand, have been observed with increasing time of exposure. The alterations observed may be due to the physiological disfunctioning of the haemopoietic tissue or may be due to the effect on the bone marrow. The effect of fenvalerate is more pronounced than that of cypermethrin.  相似文献   

2.
The effects of exposure to LC50 (10.5 mg/l) for 96 h and to a sublethal concentration (1.05 mg/l) of Sevin for 120 days have been observed on some haematological, biochemical and enzymatic parameters of Channa punctatus. The fish were hyperglycemic and hyperlactemic and the glycogen content of the liver and muscles decreased, but the lactic acid content of two tissues increased. The activity of hexokinase increased in the kidney, intestine, liver and muscles but decreased in the gills and brain. The activity of lactate dehydrogenase decreased in the kidney and intestine, and increased in the liver, muscles, brain and gills. The pyruvate dehydrogenase activity decreased in all the six tissues. Both the exposures produced a decrease in the succinate dehydrogenase activity of the liver. The enzyme activity decreased in the brain, gills and muscles after chronic exposure, whereas the kidney and intestine showed an elevation in enzyme activity.  相似文献   

3.
Exposure of Channa striatus over 24 h to 40% and 80% of the LC50;24h of the three pyrethroids cypermethrin, permethrin, and fenvalerate did not cause any significant changes in the levels of total protein and free amino acids in the liver and muscle tissues of the fish. After 96 h exposure, the protein amino acid levels are altered significantly.  相似文献   

4.
The LC50-value of diazinon for Brachydanio rerio decreases from 2.3 to 2.12 mg/1 during the time from 24 to 96 h. In the course of exposure for 24 to 288 h against 0.26 to 2.08 mg/1 diazinon the activity of acetylcholinesterase as well as acid and alkaline phosphatases decreases to 20.… 30% as a minimum. The decrease of the enzymatic activities in the brain tissue is more time-dependent than concentration-dependent, which may de due to the respective metabolites of diazinon.  相似文献   

5.
Concern has been raised that the increased use of pesticides in intensive aquaculture practices may cause adverse sublethal effects to non-target aquatic species. Azamethiphos is an organophosphate (OP) pesticide used to combat sea lice infestations in farmed salmonids. Here, the sublethal impact on the blue mussel, Mytilus edulis, of short term exposure to azamethiphos was determined. The testing regime included biomarkers of exposure (acetylcholinesterase activity), cytotoxicity (neutral red retention), immune function (phagocytic index) and physiological condition (feeding rate). The distribution and sensitivity of M. edulis acetylcholinesterase to inhibition by azamethiphos was first determined, yielding IC(50) values of 0.736 and 1.30 mg l(-1) for gill and haemolymph, respectively. Exposure of mussels to 0.1 mg l(-1) azamethiphos for periods of up to 24h caused a significant reduction in acetylcholinesterase activity in both the haemolymph (P<0.0002) and the gill (P<0.002), alteration in cell viability (P<0.02) and decrease in phagocytic index (P<0.03). The feeding rate remained unaffected. The results support the hypothesis that, in addition to its neurotoxic effects, azamethiphos can modulate haemocyte function and immune defence in M. edulis at environmentally relevant concentrations after only a few hours.  相似文献   

6.
Heteropneustes (Saccobranchus) fossilis (Pisces; Clariidae) is exposed to the biocides Chlordane, Aldrin, Metasystox, Dichlorvos, Carbofuran and Sevin for 30 d at a concentration of the 1/15 fraction of LC50;96h with daily exchange of the medium. At intervals of 5 d the respiration rate was determined for 1 h. In addition, after the end of tests 13 haematological parameters as well as the activities of the adenosine triphosphatases and the acetylcholinesterase were determined in the liver, the kidney and the gills. During all exposures to biocides the respiration rate decreases significantly with the test time. At all exposures the blood concentrations of glucose, sodium- and chloride-ions show a significant increase, whereas the cholesterin content and the clotting time decrease significantly. The ATPase activity is significantly reduced only by Aldrin and Chlordane. A significant reduction of the acetylcholinesterase activity occurs in each of the three investigated tissues only for Metasystox and Dichlorvos and in the liver in addition also for Chlordane, Aldrin and Carbofuran. Therefore, the respiration rate and haematological criteria permit a general stress indication, enzymatic activities constitute a specific indication of individual groups of biocides, so that a systematic analysis of these three indication groups will probably provide a specific resultant statement in a biomonitoring system due to the specific inhibition pattern.  相似文献   

7.
The aim of this research was to assess the impact caused by a long‐term pollution by fluoride and heavy metals in two soils (PS1 and PS2) near an aluminium smelter in Slovakia, on soil microbial biomass C (MBC), basal respiration, metabolic quotient (qCO2) water‐soluble organic C (WSOC) and enzymes activities involved in the C, N and P biogeochemical cycles. An unpolluted soil was used as control (C0). Results obtained for soil fluoride content reflected a gradient of fluoride exposure in topsoils of contaminated sites. Decreases in microbial and enzymatic activities and in MBC to organic C ratio were found in PS2 site, which is closer to the smelter and exhibited the highest fluoride content. PS1‐soil showed an extreme alkaline pH caused by leaching of waste effluents from the smelter dumping site, higher contents of Zn, Cu, Pb and Cd, significantly larger MBC, qCO2 and catalase and urease activities, and much larger basal respiration and dehydrogenase activity than PS2 and C0‐soil. Phosphatase, β‐glucosidase and BAA‐protease were negatively correlated with WSOC, basal respiration and dehydrogenase activity, and showed some degree of inhibition in polluted sites. These results may indicate different responses of microbial communities to ecosystem disturbances, caused by the drastic changes in soil's physicochemical properties as result of the long‐term emissions of fly ash with high levels of contaminants that are still affecting soil microbial and enzymatic activities.  相似文献   

8.
The use of sequential measurements of hemolymph cholinesterase activities as a non-invasive biomarker of seasonal organophosphate/carbamate exposure was investigated for the tropical scallop, Euvola (Pecten) ziczac. Overall activities of both acetylcholinesterase and butyrylcholinesterase were relatively high compared to studies with bivalve tissues. Acute in vivo experiments showed inhibition of hemolymph acetylcholinesterase activity at concentrations of the organophosphate insecticide chlorpyrifos of 0.1, 1 and 10 ng l(-1). Monthly sampling of hemolymph from scallops at two sites in Bermuda over a 15 month period showed seasonal acetylcholinesterase and butyrylcholinesterase inhibition. Direct and indirect evidence suggests that this inhibition did not relate to biochemical or physiological changes associated with gonad maturation and spawning, but rather reflected diffuse contamination of the marine environment by cholinesterase inhibitors or increased bioavailability of such inhibitors at these times. Repetitive sampling of scallop hemolymph for cholinesterase activities represents a rapid, sensitive and non-invasive method for assessing seasonal, sublethal pesticide exposure in these commercially important bivalves and suggests a wider use in marine pollution monitoring.  相似文献   

9.
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10.
The synergistic effects of sulfoxide on the effects of carbaryl in the snail Lymnaea acuminata were studied. Snails were exposed to 40 % and 80 % of 48 h LC50 doses of synergist, carbaryl mixture (5 : 1). While the concentration of carbaryl present in the mixture would not bring about any change in carbohydrate metabolism, there was a marked decrease in the AChE activity, glycogen levels and an increase in lactic acid and a reduction of sugar levels when the snails were exposed to a carbaryl synergist mixture. Sulfoxide alone also caused a decrease in glycogen levels and an increase in lactic acid levels. These changes, however, were smaller as compared to those resulting from exposure to the mixtures.  相似文献   

11.
The haematological, biochemical, and enzymological alterations produced on exposure of Channa punctatus to LC50 (11.2 mg/L) for 96 h and to a sublethal concentration (1.12 mg/L) of cadmium (Cd2+) for 15, 30, 60, and 120 days have been studied. The fish were hypoglycemic and hypolactemic. The pyruvate content of blood and liver decreased in acute and all stages of chronic exposure except for 30 days where significant increase was recorded. Depletion was noted in the total protein and glycogen content of liver and muscle, and the level of lactate in liver in the two types of exposure. The levels of muscle lactate and pyruvate increased in both exposures. The activities of hexokinase, glucose-6-phosphatase, and lactate dehydrogenase decreased in liver after 96 h and all stages of chronic exposure except 30 days. The activities of hexokinase and lactate dehydrogenase in muscle and glutamate-oxalacetate transaminase and glutamate-pyruvate transaminase in serum, liver, and muscles increased in all exposures. The activities of succinate and malate dehydrogenases in liver and muscles decreased after acute and all stages of chronic exposure. The above results suggest that glycolysis and gluconeogenesis were impaired in liver but glycolysis prevailed in muscle. Aerobic oxidation is adversely affected in metal exposed fish, while proteolysis was increased.  相似文献   

12.
The aim of the present study was to evaluate the mixed function oxidase (MFO) system and the forms of supposed cytochrome P-450 in the liver of black-headed gulls (Larus ridibundus) feeding in a lagoon and on a garbage dump. Tissue levels of polychlorinated biphenyls (PCBs) were also determined. Ethoxyresorufin 10-deethylase (EROD) and aldrin epoxidase activities were higher in the dump gulls than in the lagoon gulls. A marked thickening of the proteins in the cytochrome P-450 area, particularly of P-450c and P-450d, was also found in the dump gulls. No relationship was found between MFO activity and tissue chlorinated hydrocarbon levels.  相似文献   

13.
The relationships among cytochrome P450 induction in marine wildlife species, levels of fluorescent aromatic compounds (FAC) in their bile, the chemical composition of the inducing compounds, the significance of the exposure pathway, and any resulting injury, as a consequence of exposure to crude oil following a spill, are reviewed. Fish collected after oil spills often show increases in cytochrome P450 system activity, cytochrome P4501A (CYP1A) and bile fluorescent aromatic compounds (FAC), that are correlated with exposure to polycyclic aromatic hydrocarbons (PAH) in the oil. There is also some evidence for increases in bile FAC and induction of cytochrome P450 in marine birds and mammals after oil spills. However, when observed, increases in these exposure indicators are transitory and generally decrease to background levels within one year after the exposure. Laboratory studies have shown induction of cytochrome P450 systems occurs after exposure of fish to crude oil in water, sediment or food. Most of the PAH found in crude oil (dominantly 2- and 3-ring PAH) are not strong inducers of cytochrome P450. Exposure to the 4-ring chrysenes or the photooxidized products of the PAH may account for the cytochrome P450 responses in fish collected from oil-spill sites. The contribution of non-spill background PAH, particularly combustion-derived (pyrogenic) PAH, to bile FAC and cytochrome P450 system responses can be confounding and needs to be considered when evaluating oil spill effects. The ubiquity of pyrogenic PAH makes it important to fully characterize all sources of PAH, including PAH from natural resources, e.g. retene, in oil spill studies. In addition, such parameters as species, sex, age, ambient temperature and season need to be taken into account. While increases in fish bile FAC and cytochrome P450 system responses, can together, be sensitive general indicators of PAH exposure after an oil spill, there is little unequivocal evidence to suggest a linkage to higher order biological effects, e.g. toxicity, lesions, reproductive failure.  相似文献   

14.
Large mysticete whales represent a unique challenge for chemical risk assessment. Few epidemiological investigations are possible due to the low incidence of adult stranding events. Similarly their often extreme life-history adaptations of prolonged migration and fasting challenge exposure assumptions. Molecular biomarkers offer the potential to complement information yielded through tissue chemical analysis, as well as providing evidence of a molecular response to chemical exposure. In this study we confirm the presence of cytochrome P450 reductase (CPR) and cytochrome P450 isoenzyme 1A1 (CYP1A1) in epidermal tissue of southern hemisphere humpback whales (Megaptera novaeangliae). The detection of CYP1A1 in the integument of the humpback whale affords the opportunity for further quantitative non-destructive investigations of enzyme activity as a function of chemical stress.  相似文献   

15.
In this study, Fagopyrum esculentum (common buckwheat) sprayed with nickel (Ni) (0, 0.5, 1.0, 3.0, and 5.0 mM) for different duration has been investigated for Ni accumulation, malondialdehyde (MDA), total phenolics, and phenolic acids. Ni accumulation significantly increased in dose‐dependent manner. Plants exposed for 72 h, showed visible damages as chlorosis and irreversible necrosis. The MDA and total phenolic contents increased at 24 h of Ni treatments. HPLC data revealed that phenolic acids are in good correlation with concentration and durations of treatments. After 24 and 48 h the contents of chlorogenic, p‐hydroxybenzoic, hesperetic, p‐anisic, and caffeic acids increased in Ni treated leaves. On the other hand, p‐hydroxybenzoic, hesperetic, p‐anisic, p‐coumaric, caffeic acids contents decreased after 72 h of Ni exposure. Vanillic and cinnamic acid followed same pattern and increased significantly at 3.0 and 5.0 mM after 48 h of Ni exposure. It may suggest that buckwheat can be possible hyperaccumulators of Ni, because of high Ni accumulation in tissues through foliar treatment. Furthermore, the analyzed phenolic acids have potential role as antioxidants, which provide tolerance to buckwheat against Ni treatment.  相似文献   

16.
通过静态模拟实验,研究不同浓度(0.005、0.01、0.025、0.05和0.1 mg/L)菲暴露96 h后,对斜生栅藻的生长、自由基含量、抗氧化系统以及脂质过氧化产物(MDA)的影响.结果表明,0.01 mg/L菲开始对藻细胞生长产生显著抑制作用,在此浓度下电子自旋共振检测到的自由基信号(g=2.0033,幅宽10.15 mT)显著增强;在浓度设置范围内,超氧化物酶歧化酶、过氧化物酶、谷胱甘肽-S-转移酶活性均被显著诱导,显示出抗氧化系统的应激机制.谷胱甘肽和MDA含量均在0.025 mg/L时被显著诱导.这说明斜生栅藻对菲暴露比较敏感,0.01 mg/L即已显示胁迫效应,自由基的诱导是斜生栅藻产生损伤的重要原因,藻细胞的生长量是比较敏感的损伤指标.  相似文献   

17.
The use of biomarkers to evaluate the biological effects of chemical pollutants in marine organisms represents a recent tool in the monitoring field responding to the need to detect and assess the effects of chemical contaminants on the biota. The aim of the present work was the field application of the integrated use of acetylcholinesterase (AChE) and antioxidant enzymes (catalase--CAT, glutathione peroxidase--GSH-Px), for detecting the possible exposure/effect induced by chemical pollutants in native marine organisms from a coastal marine area, represented by Salento Peninsula (Italy), that shows a coastline of high environmental value, but under constant urban pressure, including agriculture activities, widely diffused in the whole hinterland. Eight sampling stations were chosen: four not urbanized areas considered "uncontaminated" controls and four clearly exposed to anthropogenic impact. The bioindicator species studied were a sessile invertebrate, Mytilus galloprovincialis, and a benthic teleost fish, Mullus barbatus.AChE activity in M. galloprovincialis revealed significant differences among places; the minimum values observed (3.9+/-1.8 nmolmin(-1)mg(-1)) was about 50% reduced with respect to the maximum found (11.4+/-0.9 nmolmin(-1)mg(-1)). The reduction in AChE activity observed in two control stations could be explained by the leaching of pesticides into the sea from the agricultural lands. Moreover, the inhibition of AChE activity by heavy metals besides pesticides, can also explain the reduction of the enzymatic activity observed in an industrialized and harbour area. In M. galloprovincialis AChE activity showed a significant inverse correlation with catalase activity but not with glutathione peroxidase that did not significantly change in animals sampled from the eight stations. Also in M. barbatus AChE activity showed significant differences among places; it was inversely correlated with liver GSH-Px activity, but not with catalase activity, that did not show any significantly variation in animals sampled in the different stations.In conclusion, the integrated use of AChE and antioxidant enzymes (catalase or glutathione peroxidase) in M. galloprovincialis and M. barbatus, two species living in different compartment of marine coastal ecosystem, can find a useful application within the framework of marine coastal environment monitoring programs for detecting the possible exposure/effect induced by chemical pollutants, including pesticides, on living marine organisms.  相似文献   

18.
为了揭示湖滨带土地利用与覆被改变对土壤有机碳库及生态功能的影响,本文选取了巢湖湖滨带（北岸）9个典型样方,分析和比较了表层（0~30 cm）土壤有机碳组分特征以及相关酶的活性.结果表明,巢湖湖滨带不同采样点土壤总有机碳（TOC）含量变化范围为2.88~11.2 g/kg,平均含量为9.12 g/kg,其中原生芦苇（Phragmites australis）湿地土壤TOC含量最高（11.2 g/kg）,而芦苇群落消失后形成的荒滩土壤TOC含量最低,仅为2.88 g/kg.表征湖滨带湿地缓冲性能的土壤阳离子交换量（CEC）也以原生芦苇湿地土壤为最高,并与TOC含量呈现明显正相关.湖滨带表层土壤溶解性有机碳（DOC）和易氧化有机碳（EOC）含量变化范围分别为150~370 mg/kg和1.7~5.2 g/kg,其变化幅度明显高于TOC,其中DOC含量各采样点差异最为显著.除多酚氧化酶外,次生水柳林（Homonoia riparia Lour.）表层土壤几种酶的活性较原生芦苇湿地土壤皆有所上升,特别是蔗糖酶活性增加幅度最为明显.受人类活动干扰较大的湖滨绿地公园和人工草滩土壤过氧化氢酶、脲酶和蔗糖酶酶活性普遍显著低于原生芦苇湿地.除多酚氧化酶外,土壤中几种酶活性与土壤有机碳组分EOC和DOC含量均呈现显著的正相关,其中蔗糖酶活性与DOC含量之间相关系数最高（r=0.907）,其相关性均达到极显著水平.土壤溶解性有机碳和蔗糖酶可以作为表征因土地利用与覆被变化导致湖滨带湿地退化以及生态恢复效果的敏感性指标.  相似文献   

19.
A pot experiment was conducted to investigate microbial characteristics and the biodegradation process of bensulfuron‐methyl (BSM) in a rhizosphere soils planted with different riparian plants. The results showed that microbial population decreased with BSM addition in the rhizosphere, especially for bacteria and fungi. The activities of the dehydrogenase (DHase) were stimulated firstly, due to BSM addition, but then were inhibited, and recovered to the initial level, while the activities of the phosphatase and urease showed obviously decreasing trend throughout the whole experiment. Rhizosphere soil substrate‐induced respiration (SIR) was depressed by BSM, especially at the initial 14 days of incubation. Compared to Zizania aquatica and Phragmites australis, Acorus calamus showed a significantly (p < 0.05) higher DHase activity and larger SIR in the rhizosphere soils treated with BSM, which means that A. calamus can effectively alleviate inhibitory effect of the sulfonylurea herbicide addition on microbial activity. There were significant (p < 0.05) differences in microbial degradation dynamics of BSM in the rhizosphere soils among three kinds of riparian plants. A. calamus displayed a significantly (p < 0.05) higher degradation efficiency of BSM in the rhizosphere soils, followed by Z. aquatica and P. australis. The residual BSM concentration in A. calamus rhizosphere soil was 23.1 and 32.2% lower than that in Z. aquatica and P. australis rhizosphere soils, respectively, indicating a greater improvement effect on biodegradation of BSM in A. calamus rhizosphere soils.  相似文献   

20.
After the Hebei Spirit oil spill incident (7th December, 2007) in the west coast of Korea, contamination of biliary PAH metabolite and hepatic biomarkers in a pelagic and a benthic fish was monitored for 1 year. Concentrations of 16 PAHs and alkylated PAHs in fish muscle were highest (22.0 ng/g d.w. for 16 PAHs and 284 ng/g d.w. for alkylated PAHs) at 5 days after the spill and then decreased rapidly to background levels at 11 months after the spill. Fish from the oiled site had elevated biliary PAH metabolite concentrations immediately after the spill; these declined steadily in both species, but were still above reference site concentrations 2 months after the spill. Oiled-site fish showed hepatic CYP 1A induction whose trend closely followed those of biliary PAH metabolite concentrations, implying continuous exposure to PAHs. Brain acetylcholinesterase activity was not related to oil exposure.  相似文献   

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