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71.
多环芳烃的海洋环境行为及其代谢产物的研究进展   总被引:1,自引:0,他引:1  
多环芳烃是一类广泛存在于环境中的持久性有机污染物,具有"三致"作用.环境中多环芳烃的某些不完全代谢产物同样可能具有持久性,有些甚至比母体多环芳烃的毒性更强,有可能对环境造成更大的危害.本文介绍了近年来国内外有关多环芳烃的海洋环境行为及其代谢产物毒性方面的研究进展,并重点对代谢产物的分析方法,包括高效液相色谱、气相色谱、气相色谱-质谱联用和液相色谱-质谱联用等,进行了总结,最后对该领域的研究方向进行了展望.  相似文献   
72.
As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs). In the present study, the toxicity of dimethyl phthalate (DMP),diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch. In embryo toxic test, embryos incubated at the highest concentration of DMP,DEP and DBP solutions showed significantly high abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control. Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP. Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos of 1-1. diversicolor supertexta can be used to indicate toxicity of the PAEs.  相似文献   
73.
在水温为25~31℃、p H 7.70~8.17、溶解氧≥5.0mg/L、自然光照的条件下,作者采用半静水法研究了亚硝酸态氮与非离子氨在不同盐度条件下对花鲈(Lateolabrax maculatus)幼鱼(50.33 g±4.35 g)的急性毒性、半致死量浓度、安全质量浓度及不同盐度条件下氨氮胁迫对花鲈幼鱼耗氧率与排氨率的影响。结果表明,花鲈幼鱼在盐度0、10、20时,亚硝酸盐安全浓度分别为16.357、52.540、58.622 mg/L,总氨氮安全浓度分别为0.794、4.625、5.163 mg/L,非离子氨安全浓度分别为0.584、2.313、1.951 mg/L。实验结果说明,盐度和氨氮联合胁迫对花鲈幼鱼的耗氧率、排氨率有显著影响,盐度10时耗氧率和排氨率最低。  相似文献   
74.
长江口滨岸潮滩底栖泥螺受铅污染的急性毒理试验   总被引:4,自引:0,他引:4  
为了评价长江口滨岸潮滩沉积物中重金属铅对底栖动物的影响,进行了底栖动物泥螺的24h急性毒理学试验研究。结果表明:泥螺的半致死剂量是0.275g/L,全致死剂量是11.5g/L;对泥螺体内重金属累积量的分析表明:泥螺体内Pb的含量随试验组浓度的增高而增多,试验组的Pb浓度和泥螺累积的Pb含量符合三次函数;泥螺体内Pb的增加对泥螺富集Cu、Zn的影响是使其富集量有所下降,在浓度为4g/L时稍有回升;Pb含量的增加对泥螺富集Cr的影响是在浓度为0.1 1 8g/L时出现富集较大量,说明底栖动物富集的重金属元素问具有一定的协同作用。  相似文献   
75.
三种重金属离子对东方小藤壶幼虫的急性毒性效应   总被引:9,自引:0,他引:9  
周媛  杨震  许宁  英瑜  唐学玺 《海洋科学》2003,27(8):56-58
研究了3种不同浓度重金属离子对东方小藤壶(Chthamalus challengeri)二期幼虫的急性毒性效应。结果表明:铜、锌、镉离子均有较高的毒性,它们对二期幼虫的12 h半致死剂量分别为1.00mg/L、2.29mg/L和0.56mg/L,24h半致死剂量分别是0.71mg/L、1.71mg/L和0.14mg/L,毒性大小依次排为Cd~(2+)>Cu~(2+)>Zn~(2+)。  相似文献   
76.
After the Aznalcóllar mining spill (April, 1998) different ecosystems along the Guadiamar river and the Guadalquivir estuary were impacted by high concentrations of metals. The concentration of metals Zn, Cd, Pb, Cu and As has been detected as a good tracer of the pathway of the toxic spill. Different individuals of the fish Solea senegalensis and the clam Scrobicularia plana were exposed to contaminated sediments after the accidental spill in the south-west Spain. The induction of metallothioneins in fish and the bioaccumulation of metals in clams were determined in different tissues to determine the biological adverse effect associated with the heavy metals from the spill. A relationship between the enrichment of metals in the tissues and the induction of metallothioneins was determined for those assays performed using contaminated sediments. The bioaccumulation of metals indicates that the risk associated with the spill should be continuously evaluated to establish the sublethal effects related to the accident.  相似文献   
77.
王丽平  郑丙辉  孟伟 《海洋通报》2007,26(4):111-115
在实验室条件下研究了多环芳烃荧蒽和铜对三角褐指藻的单一和联合毒性。结果表明:在本实验所测试的浓度范围内,荧蒽(0~0.315μg/mL)和铜(0~1.262μg/mL)分别对该藻的生长产生了一定的影响,且都呈现较好的剂量-效应关系;其中当荧蒽浓度升高至0.079μg/mL或铜离子浓度升至0.317μg/mL时,开始明显抑制藻种群的增殖。经回归分析求得荧蒽和铜对三角褐指藻的72hEC50分别为(0.103±0.009)μg/mL和(0.531±0.037)μg/mL。在联合毒性实验中,定义0.5×EC50(荧蒽) 0.5×EC50(铜)=1个毒性单位(TU)。荧蒽和铜混合后,对三角褐指藻的72hEC50为(1.093±0.085)TU,其联合毒性效应方式表现为拮抗作用。  相似文献   
78.
Hg,Cu,Cd,Zn 对真鲷仔鱼的急性毒性研究   总被引:5,自引:1,他引:5  
蓝伟光  陈霓 《海洋科学》1991,15(5):56-60
本文采用静水生物试验法测定了Hg,Cu,Cd,Zn对真鲷仔鱼(2周龄)的急性毒性。结果表明:Hg,Cu,Cd,Zn对真鲷仔鱼24h的LC_(50)分别为0.025,0.31,5.00和3.70 mg/L,48h的LC_(50)分别为0.016,0.24,1.72和2.22mg/L,72h的LC_(50)分别为0.006,0.11,O.56和0.92mg/L,96h的LC_(50)分别为O.004,0.07,0.27和0.44 mg/L。Hg,Cu对真鲷仔鱼的影响极为显著,Zn,Cd的影响虽然很大,但比Hg,Cu低得多。Cd的毒性比Zn强,但毒理作用较为缓慢。4种重金属的毒性顺序为Hg>Cu>Cd>Zn。  相似文献   
79.
Bioassay using the marine bacteria,Vibrio fischeri and rotifer,Brachionus plicatilis, and chemical analyses were conducted to assess the toxicity of the various sewage sludges, one of the major ocean dumped materials in the Yellow Sea of Korea. Sludge elutriates extracted by filtered seawater were used to estimate the ecotoxicity of the sludge. Chemical characterization included the analyses of organic contents, heavy metals, and persistent organic pollutants in sludge. Bacterial bioluminescent inhibition (15 min), rotifer mortality (24 hr) and rotifer population growth inhibition (48 hr) assay were conducted to estimate the sludge toxicity. EC50 15 min (inhibition concentration of bioluminescence after 15 minutes exposed) values by Microtox® bioassay clearly revealed different toxicity levels depending on the sludge sources. Highest toxicity for the bacteria was found with the sludge extract from dyeing waste and followed by industrial waste, livestock waste, and leather processing waste. Clear toxic effects on the bacteria were not found in the sludge extract from filtration bed sludge and rural sewage sludge. Consistent with Microtox® results, rotifer neonate mortality and population growth inhibition test also showed highest toxicity in dyeing waste and low in filtration bed and rural sewage sludge. High concentrations of persistent organic pollutants (POPs) and heavy metals were measured in the samples from the industrial wastes, leather processing plant waste sludge, and urban sewage sludge. However, there was no significant correlation between pollutant concentration levels and the toxicity values of the sludge. This suggests that the ecotoxicity in addition to the chemical analyses of various sludge samples must be estimated before release of potential harmful waste in the natural environment as part of an ecological risk assessment.  相似文献   
80.
汞对三角褐指藻一次培养毒性实验表明,当无机汞(HgCl_2)浓度为5μg/dm~3时能抑制细胞分裂,汞浓度达到80μg/dm~3,则细胞完全停止分裂。甲基汞浓度为1μg/dm~3时能抑制细胞分裂,浓度为25μg/dm~3时,则完全抑制细胞分裂。有机络合剂对无机汞有解毒作用,这表明汞的毒性与汞在溶液中形态有关。根据实验结果,分析讨论了汞对三角褐指藻的毒性机理。无机汞和甲基汞对细胞毒性的差别,可能与它们同细胞膜的结合及传输方式不同所致。  相似文献   
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