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591.
采用野外采样和室内分析,试验结果表明池塘、稻田、水库水中Cu有超标样本,溪河水中Cu含量较低,不同养殖水体底泥和鱼肉中Cu均无超标样本。模拟结果表明鱼肉中Cu同水中Cu有直线关系,稻田水中Cu同鱼肉中Cu呈倒数曲线关系,因此控制养殖水中Cu的输入对鱼产品质量安全有重要意义。  相似文献   
592.
Concentrations of mono- (MBT), di- (DBT), and tri-(TBT) butyltin compounds were measured in eggs, liver, and muscle of nine species of fish from four regions of the Baltic Sea - the Firth of Vistula, the Gulf of Gdańsk, Puck Bay, and the mouth of the Vistula River. The overall concentration ranges among all the fish sampled from the four sites were: < 7 to 79 ng/g for MBT, 6 to 1100 ng/g for DBT, 7 to 3600 ng/g for TBT, and 16 to 4800 ng/g for total BTs, on a wet wt basis. The highest concentration of total BTs was found in herring liver from the Firth of Vistula (4800 ng/g, wet wt) and in roach muscle from Puck Bay (3300 ng/g, wet wt), while the least concentration was found in burbot eggs and liver from the Vistula River (39 and 32 ng/g, wet wt, respectively). TBT was the major form of BTs present in most samples analyzed. Sediment samples collected from shipyards in the Gulf of Gdańsk contained butyltin concentrations ranging from 1.2 to 46 μg/g (dry wt) for MBT, 2.0 to 42 μg/g for DBT, and 2.6 to 40 μg/g for TBT. As with the fish, the majority of the BTs in sediment were present as TBT, which suggested recent exposure of the aquatic environment of the region to TBT.  相似文献   
593.
Common carp (Cyprinus carpio) collected from four sites in the Red River of the North in 1994 were analyzed for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), selenium (So), and zinc (Zn). Concentrations differed among liver, muscle, and whole body. Generally, trace element concentrations were the greatest in livers while concentrations in whole bodies were greater than those in muscle for Cd, Cu, Ni, Pb, and Zn, and concentrations in muscle were similar to whole body for As and Se. Concentrations of Cr were lower in liver than either muscle or whole body. Correlations between liver and whole body concentrations were stronger than those between liver and muscle concentrations, but the strongest correlations were between muscle and whole body concentrations. Examination of tissue concentrations by collection sites suggested that, for a general survey, the whole body may be the most effective matrix to analyze.  相似文献   
594.
藻毒素对鱼类肝脏的毒理学效应   总被引:4,自引:0,他引:4       下载免费PDF全文
以鱼类肝脏为靶器官,研究了藻毒素对鱼类的毒性影响.结果表明,藻毒素在注射和口服两种不同的染毒方式下,均可引起受试鱼类发生急性中毒死亡.对中毒鱼类进行解剖分析发现,受试鱼类的肝/体重比高于对照组.说明无论哪种给药方式,藻毒素都会迅速地、专一地作用于鱼类肝脏,引起鱼类肝脏充血红肿,出现血斑.通过对鱼类肝脏组织碱性磷酸酶(ALP)同功酶谱的分析,可以发现在两种不同染毒条件下藻毒素各剂量组的ALP同功酶谱与对照组相同,均有ALP11~ALP55条带,只是高剂量组较低剂量组ALP1~ALP3 3条带的着色深,并可使ALP同功酶各组分的相对活性上升.试验结果显示,藻毒素具有极高的细胞选择性和专一生物活性,其在生物机体内所引发的许多细胞学变化主要是对生物体肝脏酶系统的破坏所致,必须引起人们的重视.  相似文献   
595.
氯代苯胺对斑马鱼的急性毒性及3D-QSAR分析   总被引:9,自引:0,他引:9  
研究了2-氯-4-硝基苯胺、4-氯-3-硝基苯胺、2-氯-5-硝基苯胺、2,4-二氯苯胺、3,4-二氯苯胺、2,5-二氯苯胺、2,3-二氯苯胺对斑马鱼(Brachydanio rerio)的96 h急性毒性,96 h LC50分别为6.99,2.58,8.63,7.79,6.08,5.23,0.49 mg/L.运用三维定量结构活性相关模型(3D-QSAR)对这些化合物的毒性效应和构效关系进行了分析和评价,估算毒性值与实际观测值相关性较好,相关系数R2=0.907.   相似文献   
596.
597.
Emissions of Hg, Pb, and Cd to air aretransported over wide areas in Europe and deposited far awayfrom their sources. About 80% of the atmospheric depositionof these metals in south Sweden originate from emissions inother countries. As a result of the increased anthropogenicdeposition the concentrations of Hg, Pb, and Cd in the morlayer of forest soils have increased considerably, mainlyduring the 20th century. Although the atmosphericdeposition of these elements has declined during the mostrecent decades, the reduction of the input of Hg and Pb isnot sufficient to prevent a further accumulation. Theconcentrations of Hg and Pb are still increasing by ca. 0.5and ca. 0.2% annually in the surface layer of forest soils.In contrast, the Cd concentration is currentlydecreasing in a large part of Sweden as a result of bothdeposition decreases and enhanced leaching induced by soilacidification. The accumulation factors of Hg and Pb,especially in the forest topsoils of south Sweden, arealready above those at which adverse effects on soilbiological processes and organisms have been demonstrated instudies of gradients from local emission sources andlaboratory assessment. There are also indications of sucheffects at the current regional concentrations of Hg and Pbin mor layers from south Sweden, judging from observationsin field and laboratory studies. There is an apparent riskof Pb induced reduction in microbial activity over parts ofsouth Sweden. This might cause increased accumulation oforganic matter and a reduced availability of soil nutrients.At current concentrations of Hg in Swedish forest soils,effects similar to those of Pb are likely. Increasedconcentrations of these elements in organs of mammals andbirds have also been measured, though decreases have beendemonstrated in recent years, related to changes inatmospheric deposition rates. As a result of current andpast deposition in south Sweden, concentrations of Hg infish have increased about fivefold during the 20thcentury. This implies risks for human health, when fish frominland waters are used for food. Although the concentrationof Hg in fish has decreased ca. 20% during the last decade,probably as a result of the reduced deposition, the levelstill exceeds the general limit (0.5 mg kg-1) in about half(ca. 40 000) of the Swedish lakes. In order to reduceconcentrations in fish to the level recommended, and avoidfurther accumulation of Hg in soils, the atmosphericdeposition has to be reduced to ca. 20% of the current deposition rate. This can only be achieved by international co-operation.  相似文献   
598.
ABSTRACT: The relation offish community composition to riparian cover at two spatial scales was compared at 18 streams in the agricultural Minnesota River Basin. The two spatial scales were: (1) local riparian zone (a 200 meter wide buffer extending 2 to 3 kilometers upstream of the sampling reach); and (2) the upstream riparian zone (a 200 m wide buffer on the mainstem and all perennial tributaries upstream of the sampling reach). Analysis of variance indicated that streams with wooded‐local riparian zones had greater fish species richness (means = 20 and 15, respectively) and Index of Biotic Integrity (IBI) scores (means = 40 and 26, respectively) than streams with open‐local riparian zones. Streams with wooded‐upstream riparian zones tended (were not statistically significant) to have greater numbers of species (means = 19 and 15, respectively) and IBI scores (means = 33 and 28, respectively) than streams with open‐upstream riparian zones. There was no significant interaction between the riparian zone conditions at the two scales. This study suggests that maintenance of wooded riparian cover along streams could be effective in maintaining or improving fish community composition in streams draining heavily agricultural areas.  相似文献   
599.
本工作建立了鱼中从四氯到八氯的二苯并二(口恶)(口英)和二苯并呋喃的分析方法。鱼样品经消化后以己烷提取,提取液经两套层析柱净化后,用反相HPLC进一步净化并分为两个级份。采用GC/SIM-MS测定各PCDD和PCDF。  相似文献   
600.
辽东半岛海域鱼贝中有机氯农药残留及其风险评估   总被引:1,自引:0,他引:1  
2011年1月-2012年5月间采集了辽东半岛海域11种鱼类和2种贝类样品,分析了其可食部位中22种有机氯农药的残留量,评估了其中DDTs和HCHs的残留对人体健康的风险。在所调查样品中HCB、HCHs和DDTs是主要的污染物,样品中OCPs残留量为57.12~546.15μg·kg-1。利用污染指数计算法评估,旅顺海域小黄鱼、鳙鱼、中国斗鱼和偏口鱼未受到HCHs的污染,棒花鱼受到HCHs轻度污染,其它鱼种样品均受到重度污染,而对于DDTs,只有鲫鱼未受到污染,其它鱼种样品均受到重度污染。大黄鱼、梭鱼、黑鱼和鳙鱼体内HCHs残留量明显高于国标再残留限值,DDTs残留量符合国标标准。α-HCH、γ-HCH、β-HCH、p,p'-DDE、p,p'-DDD和p,p'-DDT的致癌风险指数范围为0.32×10-6~49.57×10-6,均低于10-4,为可接受的致癌风险;α-HCH、γ-HCH、β-HCH、p,p'-DDE的接触风险指数ERI为0.01×10-3~153.28×10-3,均小于1,为可接受的接触风险,但2012年4月的黑鱼样品上述六种农药的CRI总值高于10-4,存在潜在的致癌风险,因此,建议黑鱼的日均食用量应控制在50 g以下较为安全。  相似文献   
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