鲫鱼肝脏代谢酶和血清性激素对低浓度五氯酚的响应

研究了低浓度五氯酚暴露后鲫鱼体中几种重要分子生态毒理学指标的响应。结果表明,暴露7和15d后,五氯酚对鲫鱼血清睾酮含量产生了显著的诱导作用,并且暴露15d的睾酮含量高于暴露7d的睾酮含量,对鱼体造成了一定的繁殖损伤。暴露7d后,EROD和GST活性无显著升高,但暴露15d后,EROD和GST活性随浓度增加显著被诱导,其活性增高。研究结果也可揭示睾酮、EROD和GST对低浓度五氯酚具有高度的响应,建议作为监测和评价低浓度五氯酚对水生生态系统污染的生物标志物。      

2,2′,4,4′-四溴联苯醚(BDE-47)污染沉积物对铜锈环棱螺肝胰脏的SOD、CAT和EROD活性的影响

以实验室培养的铜锈环棱螺(Bellamya aeroginosa)为受试生物,研究了2,2′,4,4′-四溴联苯醚(BDE-47)污染沉积物对铜锈环棱螺肝胰脏超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和7-乙氧基-3-异吩唑酮-脱乙基酶(EROD)活性的影响,以揭示BDE-47与这些酶活性之间的剂量-效应和时间-效应关系.结果表明,不同水平BDE-47污染沉积物暴露后,铜锈环棱螺肝胰脏SOD和CAT活性表现出较为明显的剂量或时间依赖性效应,BDE-47可引起铜锈环棱螺肝胰脏的氧化应激,高剂量(≥160ng.g-1)BDE-47的长时间暴露可导致SOD和CAT活性显著下降,提示细胞出现氧化损伤.SOD对BDE-47胁迫的敏感性高于CAT.铜锈环棱螺肝胰脏中SOD和CAT可以作为指示低水平BDE-47污染沉积物胁迫的生物标志物.BDE-47不能诱导铜锈环棱螺肝胰脏EROD活性,但高剂量(≥160ng.g-1)或长时间BDE-47暴露则导致EROD活性显著降低.     

鱼体内EROD活性对多氯联苯类的指示作用

运用鱼体肝脏中的EROD(7 ethoxyresorufin O deethylase)活性作为生态标记物 ,来指示大连近海部分水域的多氯联苯 (PCBs)类物质的污染状况。结果表明鱼体肝脏内的EROD活性可被PCBs诱导 ,导致活性异常增高 ,并与环境中特定污染物浓度之间存在着定量响应关系 ,EROD的这个特性可以用来评估海洋生态环境健康并作为预警指标。我们选取大连近海水域部分具有代表性的站位 ,分析测定其鱼样中EROD活性 ,并结合环境化学指标进行综合分析 ,证明将EROD作为指示多氯联苯类污染物的生态标记物是切实可行的 ,该方法在海洋环境监测中具有实际应用价值。     

苯并[a]芘对鲫鱼生物标志物的影响研究

研究了苯并[a]芘暴露对鲫鱼(Carassius auratus)的几种生物标志物的影响.在鲫鱼接受3个不同质量分数苯并[a]芘(BaP)的腹腔注射14 d后,分析了其肝脏7-乙氧基-3-异吩噁唑酮-脱乙基酶(EROD)活性,以及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPx)等抗氧化酶活性和红细胞核异常(NA)率变化.结果显示:w(BaP)为1 mg/kg处理组的EROD活性显著升高(P＜0.001).w(BaP)为0.1和1 mg/kg处理组SOD活性显著低于对照组(P＜0.001),在暴露结束时,w(BaP)为1 mg/h处理组CAT活性显著低于对照组(P＜0.01),而w(BaP)为0.1和1 mg/kg处理组GPx活性被显著抑制(P＜0.001).表明BaP对EROD活性有诱导作用,而对SOD,CAT和GPx等抗氧化酶活性的抑制作用明显.所有处理组NA率与对照组均无显著差异.因此,鲫鱼EROD,SOD,CAT和GPx等酶活性的改变适于作为生物标志物,可以用来显示暴露于多环芳烃有机污染物鱼类的生活状态.      

鲫鱼对水中有机防晒剂的富集及代谢酶响应

采用半静态水体暴露方法研究了有机防晒剂对二甲氨基苯甲酸异辛酯(OD-PABA)在鲫鱼不同组织的分布、累积及生态毒理效应.结果表明,OD-PABA在不同组织中的含量随着水体暴露浓度的升高而持续升高,并在14或28d达到最大.不同浓度的OD-PABA在不同组织的生物富集因子(BCF)存在明显差异,基于暴露14d和28d计算得到的BCF值,肝脏为123~186,皮肤为117~163,肾脏为90.2~147.OD-PABA对鲫鱼肝脏EROD、PROD、BFCOD和GST活性都产生了诱导效应,其中EROD和GST的响应更为显著,最大诱导倍数分别为0.97和0.53倍.结果表明,水中的OD-PABA可在鲫鱼体内富集,并通过I相和II相代谢酶进行生物转化.     

饲料添加剂叔丁基对羟基茴香醚和抗生素诺氟沙星对剑尾鱼的毒性效应

研究了叔丁基对羟基茴香醚(butylated hydroxyanisole,BHA)和诺氟沙星(norfloxacin,NFLX)对剑尾鱼的急性毒性及其肝脏谷胱甘肽硫转移酶(GST)、丙二醛(MDA)、过氧化氢酶(CAT)及7-乙氧基异吩恶唑酮-脱乙基酶(EROD)活性的影响.结果表明,BHA和NFLX对剑尾鱼毒性大小分别属于高毒和低毒.BHA的暴露浓度为0.20mg.L-1和0.04mg.L-1时,GST和CAT活性诱导分别达到最大值;NFLX的暴露浓度为5mg.L-1时,GST和CAT均受到最大程度的诱导.随着BHA和NFLX暴露浓度的增加,GST和CAT呈现出先诱导后抑制的典型"钟型曲线"变化规律,而MDA含量和EROD活性则逐渐增加.其中,MDA和EROD响应较为敏感,适合作为BHA和NFLX暴露的生物标记物.雌雄个体酶响应的敏感程度存在一定的差异,雄性个体比雌性个体敏感.     

诺氟沙星对阿部鲻鰕鯱Ⅰ相、Ⅱ相酶活性及CYP1A1和P-gpmRNA表达影响

通过饲料暴露的方式研究了抗生素诺氟沙星（Norfloxacin,NFLX）对阿部鲻鰕鯱（Mugilogobius abei）Ⅰ相、Ⅱ相代谢酶活性以及CYP1A1和P-糖蛋白(P-gp) mRNA表达的影响。结果表明随着暴露时间的延长,NFLX对阿部鲻鰕鯱肝脏Ⅰ相代谢酶APND、 ERND均表现出先诱导后抑制的作用。24 h时NFLX的暴露浓度为20 μg?g-1对Ⅰ代谢酶APND和ERND的诱导达到最大值。当暴露时间达到168 h, APND和ERND均受到极显著抑制。Ⅱ相代谢酶GST和MDA在72 h受到最大诱导,经过168 h暴露后,GST活性逐渐恢复到正常水平,而MDA含量在50 μg?g-1浓度组仍然维持较高水平。CYP1A1和P-gp mRNA表达量随着暴露时间的延长而增加,168 h达到最大。APND、 ERND、GST、 MDA、CYP1A1 mRNA和P-gp mRNA响应敏感,适合作为NFLX暴露的生物标记物。 关键词：诺氟沙星;阿部鲻鰕鯱;肝脏酶活;CYP1A1;P-gp     

苯并(a)芘和芘暴露对梭鱼肝脏超氧化物歧化酶活性的影响

在实验生态条件下，浓度范围0．1－0．5ug/L的苯并（a)芘和芘的短期暴露（7d),50ug/L浓度组造成梭鱼肝脏SOD活性先抑制后诱导的效应，5ug/L浓度在7d的暴露中，SOD活性未出现诱导而是抑制。同样在50ug/L浓度下，苯并（a)芘暴露4d后SOD活性出现诱导，而芘在暴露7d后才出现诱导，这间接反映了苯并（a)芘和芘的毒性大小。这些结果说明梭鱼肝脏SOD活性与苯并（a)芘和芘暴露有一定的相关性，可以作为海洋环境多环芳烃污染监测的一种生物标志物。     

低质量浓度2-硝基-4′-羟基二苯胺暴露对鲫鱼鳃组织HSP70诱导的影响

采用实验室模拟的方法，以日本锦鲫（Carassius auratus）作为实验生物，运用SDS变性胶（SDS-PAGE）蛋白电泳和免疫印迹（Western Blotting）等分子生物学技术，研究了1mg／L 2-硝基-4’-羟基二苯胺（HC Orange No．1）在不同暴露时期对鲫鱼鳃组织应激蛋白HSP70诱导表达的情况，并探讨了鲫鱼鳃组织HSP70作为该有机污染物生物标志物的可行性。结果表明：鲫鱼鳃组织HSP70在暴露2d后相对于空白对照组开始有显著的表达（P〈0．05），并随着暴露天数的增加其表达量显著增加；在暴露4d后其表达量达到最大值；在暴露7d后其表达量开始下降，但可能由于长时间的有机物毒性胁迫，造成了鲫鱼鳃组织损伤和病变，HSP70在随后的暴露时间段内表达量明显下降，均显著低于空白对照组（P〈0．05），因此，鲫鱼鳃组织HSP70并不适宜作为该有机污染物在自然界水生生态系统中的生物标志物。     

两种二氯苯胺对鱼类血清性类固醇激素水平的影响

研究了2，3－二氯苯胺、2，4－二氯苯胺对斑巴鱼（Brachydanio rerio）的96h急性毒性，并将鲫鱼（Carassius auratus）分别暴露于梯度浓度的2，3－二氯苯胺、2，4－二氯苯胺2周，用放射免疫法测定空白对照组和染毒组鲫鱼血清的睾酮、17β-雌二醇浓度，结果表明二氯苯胺类化合物对鱼体内类固醇激素水平有一定影响，为可疑的环境内分泌干扰物。     

Relation of hepatic EROD activity and CYP1A level in Sebastiscus marmoratus exposed to benzo[a]pyrene

This study was designed to investigate the in vivo effects of benzo[a]pyrene (BaP) on hepatic ethoxyresorufin-O-deethylase (EROD) activity and its correlation with cytochrome P450 1A (CYP1A) protein levels in Sebastiscus marmoratus, which were exposed through a water column to BaP (10, 100, 1000 ng/L, respectively) or were treated with intraperitoneal injections of BaP (0.5, 1, 5, 10 mg/kg, respectively) every 7 d. The results showed that after 25 d of waterborne exposure to 1000 ng/L BaP, fish hepatic CYP1A levels and EROD activity were significantly induced. In contrast, EROD activity was not altered 7 d after second ip injections, whereas, CYP1A protein levels were increased. Dose-dependent increase of biliary BaP metabolites demonstrated that the catalytic activity of CYP1A was induced by treatment with BaP. The lowest observable effect concentration with regard to biliary BaP metabolites (100 ng/L) was much lower than that with reference to EROD activity (1000 ng/L). The results suggest that biliary polycyclic aromatic hydrocarbon (PAH) metabolites were shown to better reflect the contamination gradients of PAHs than EROD activity. It appeared to be necessary to measure CYP1A protein levels to complement the EROD activity in relevant toxicological assessments.     

Arsenic fractionation and contamination assessment in sediments of thirteen lakes from the East Plain and Yungui Plateau Ecoregions, China

Arsenic（As） fractions in the sediments of seven lakes from East Plain Ecoregion and six lakes from Yungui Plateau Ecoregion, China, were investigated. Results indicated that the total As concentrations in sediment samples of lakes of the East Plain Lake Ecoregion are higher than those of Yungui Plateau Lake Ecoregion. Residual As is the main fraction in sediment samples of lakes from both ecoregions, followed by reducible As and soluble or oxidizable As. The total As is correlated to oxidizable As and residual As in sediment samples from both lake ecoregions. As distribution in sediment samples of lakes of the East Plain Ecoregion appears to be affected by human activity, while the As origin mainly comes from natural sources in sediment samples of lakes in the Yungui Plateau Ecoregion. The potential ecological risk index and geoaccumulation index values suggest ＂low to moderate＂ risk degree and ＂unpolluted to moderately polluted＂ for As in the studied lake sediments.     

Fish transplantation and stress-related biomarkers as useful tools for assessing water quality

The active biomonitoring (ABM) approach was investigated using species of indigenous (from a pristine site) and transplanted (to a polluted area) fish Carassius auratus as an indicator organism of water/sediment pollution in Taihu Lake, a highly urbanized and industrialized area. The biotransformation enzymes 7-ethoxyresorufin-O-deethylase (EROD), reduced glutathione (GSH) content, catalase activities (CAT) and lipoperoxidation (as MDA) in liver were determined as stress-related biomarkers during the field exposure period. At the same time, the contents of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and heavy metals in the surface sediments of biomonitoring sites were also determined. The results indicate that the in situ exposed organisms were stressed. The marked increases of EROD, GSH, CAT and MDA in transplanted animals, suggested their potential application as biomarkers in pollution monitoring. Integrated biomarker response (IBR) was used to evaluate an integrated impact of toxicants from different polluted sites.     

Relation of hepatic EROD activity and cytochrome P4501A level in Sebastiscus marmoratus exposed to benzo[a]pyrene

This study was designed to investigate the in vivo effects of benzo[a]pyrene （BaP） on hepatic ethoxyresorufin-O-deethylase （EROD） activity and its correlation with cytochrome P4501A （CYP1A） protein levels in Sebastiscus marmoratus, which were exposed through a water column to BaP （10, 100, 1000 ng/L, respectively） or were treated with intraperitoneal injections of BaP （0.5, 1, 5, 10 mg/kg, respectively） every 7 d. The results showed that after 25 d of waterborne exposure to 1000 ng/L BaP, fish hepatic CYP1A levels and EROD activity were significantly induced. In contrast, EROD activity was not altered 7 d after second intraperitoneal injections, whereas, CYP1A protein levels were increased. Dose-dependent increase of biliary BaP metabolites demonstrated that the catalytic activity of CYP1A was induced by treatment with BaP. The lowest observable effect concentration with regard to biliary BaP metabolites （100 ng/L） was much lower than that with reference to EROD activity （1000 ng/L）. The results suggest that biliary polycyclic aromatic hydrocarbon （PAH） metabolites were shown to better reflect the contamination gradients of PAHs than EROD activity. It appeared to be necessary to measure CYP1A protein levels to complement the EROD activity in relevant toxicological assessments.     

硝基芳烃对鲤鱼肝EROD活性影响的体外研究

在体外实验条件下,研究了9种硝基芳烃化合物对鲤鱼肝脏7-乙氧基异吩唑酮-脱乙基酶(EROD)的影响.结果表明,9种硝基芳烃化合物对EROD均有激活作用,在实验浓度范围内,EROD活性与浓度之间存在剂量-效应关系.实验发现苯环上同一位置的取代基不同或同一取代基在苯环上的位置不同,对EROD的激活程度的影响也不同.     

9种硝基苯对鱼肝微粒体EROD活性的影响

混合功能氧化酶系(mixed function oxidase,MFO)中的敏感指标,7-乙氧基-异吩唑酮-脱乙基酶(7-ethoxyresorufin-O-deethylase,EROD)已作为生物标志物,应用于生态毒理学研究领域.笔者以苯并(a)芘作为阳性对照,采用鲤鱼肝脏体外直接染毒测定EROD的方法,分析了9种硝基苯对EROD活性的诱导影响.      

垃圾焚烧系统中二噁英类形成机理及影响因素

垃圾焚烧是城市中二噁英类污染的主要来源之一，因此如何控制焚烧二噁英类的形成和排放是目前研究的热点。本文探讨了垃圾焚烧过程中二噁英类的三种形成途径：原始垃圾中存在二噁英类、从头合成、前体物形成。并且进一步分析了二噁英类形成的影响因素(包括反应物、反应表面、催化剂、温度、烟气环境、氯源、水分)，从而为二噁英类的形成和排放控制提供理论基础和依据。     

Influence of combustion-originated dioxins in atmospheric deposition on water quality of an urban river in Japan

Bulk (wet and dry) deposition samples were collected in Saitama Prefecture, Japan throughout a year (February 8, 2012 to February 7, 2013) to estimate the influence of dioxins emitting from waste incinerators on river water quality. The annual deposition flux of dioxins was 3.3 ng-toxic equivalent (TEQ)/m²/year. Source identification using indicative congeners estimated that 82% of dioxin TEQ in the bulk deposition (2.7 ng-TEQ/m²/year) was combustion-originated, indicating that most of the dioxins in the deposition were derived from waste incinerators. In Saitama prefecture the annual flux of combustion-originated dioxins in depositions was apparently consistent with that of dioxin emission into the air from waste incinerators. The TEQ of combustion-originated dioxins in the deposition per rainfall was 2.4 pg-TEQ/L on annual average, exceeding the environmental quality standard (EQS) for water in Japan of 1 pg-TEQ/L. This suggests there is a possibility that dioxins in atmospheric deposition have a significant influence on the water quality of urban rivers which rainwater directly flows into because of many paved areas in the basins. The influence of combustion-originated dioxin in the deposition on the water quality of Ayase River, an urban river heavily polluted with dioxins, was estimated at 0.29 pg-TEQ/L on annual average in 2015. It seems that dioxins in atmospheric deposition from waste incinerators have a significant influence on water quality of some urban rivers via rainwater though the dioxins in the ambient air have achieved the EQS for atmosphere at all monitoring sites in Japan.