Effect of mercury and methyl parathion on the ovaries of Labeo rohita (Ham)

Adult pre-spawning fish Labeo rohita were sublethally (1/5th 96h LC50) exposed to mercuric chloride and metacid-50 (methyl parathion). Accumulation of mercury and methyl parathion was studied and it was found that pre-spawning ovary appears as a potent organ for deposition of both the pollutants. RNA/DNA ratio of the control and treated fish were studied. It was found that the signifcant decrease in RNA/DNA ratio occurs after 9 and 30 days of exposure for mercury and 30 days for methyl parathion. Fluorescence microscopic studies by acridine orange staining method were also performed to show how much it is related to biochemical alterations. In some cases loss of metachromasia is correlated with the fall in RNA/DNA ratio. Some other abnormalities like fall in stage II: stage I oocyte ratio and necrosis was also observed.     

Degradation and acute toxicity of Methidathion and Trichlorfon on Procambarus clarkii,in experimental conditions

Routine applications of organophosphate pesticides may adversely affect many nontarget organisms. Static toxicities in mature crayfish Procambarus clarkii were determined, in laboratory, for two organophosphate insecticides using 24, 48, 72 and 96‐h static tests. Three groups of 10 crayfish were exposed to 0.75 to 6 ppm for Trichlorfon and 0.2 to 0.9 ppm for Methidathion. The 24 to 96‐h LC50 values for Trichlorfon and Methidathion were from 5.14–0.99 ppm and 0.73–0.28 ppm respectively. Studies of degradation of Methidathion and Trichlorfon have been made using 1 ppm for Methidathion and 0.1 ppm for Trichlorfon. Both insecticides were degradated gradually until 96‐h. Results show that Methidathion is more toxic to P. clarkii in our medium and degradation of both pesticides is similar.     

表面活性剂十二烷基苯磺酸钠（SDBS）和十二烷基磺酸钠（SDS）对安氏伪镖水蚤的急性毒性研究(Acute Toxicity of Sodium Dodecyl Benzene Sulfonate（SDBS）and Sodium Dodecyl Sulfate（SDS）to the Copepod, Pseudodiaptomus annandalei)

为探讨表面活性剂成分对海洋桡足类生物的影响,测定了十二烷基苯磺酸钠(SDBS)和十二烷基磺酸钠(SDS)对安氏伪镖水蚤(Pseudo-diaptomus annandalei Sewell)的急性毒性作用.结果表明,SDBS对安氏伪镖水蚤雌体24h、48h、72h和96h的半致死浓度LC50分别为2.40、1.67、1.59和1.58mg·L-1,而对雄体分别为1.84、1.54、1.41和1.40mg·L-1;SDS对雌体24h、48h、72h和96h的LC50分别为54.33、30.85、25.21和15.85mg·L-1,对雄体分别为18.48、13.55、10.51和8.50mg·L-1;SDBS对雌体和雄体的安全浓度分别为0.24mg·L-1和0.32mg·L-1,而SDS对雌体和雄体的分别为2.98mg·L-1和2.19mg·L-1.结果显示,对安氏伪镖水蚤而言,SDBS比SDS的毒性更强;以半致死浓度LC50为参考依据,安氏伪镖水蚤雄体均比雌体对这两种表面活性剂敏感.     

16种除草剂对家蚕的毒性评价研究(Toxicity Evaluation of Sixteen Herbicides to Bombyx mori)

采用食下毒叶法在室内测定了二甲戊乐灵、异丙甲草胺、草甘膦铵盐等16种除草剂对家蚕的急性毒性,并根据其毒性范围进行分极,评价了其对环境的安全性.结果表明,10%啶嘧磺隆可湿性粉剂96hLC50为5.58mg·kg-(1桑叶),属于高毒;50%草甘膦可溶粉剂和80%莠灭净可湿性粉剂96hLC50分别为68.17mg·kg-(1桑叶)和111.75mg·kg-1(桑叶),属于中毒;其它13种药剂的LC50>200mg·kg-(1桑叶),属于低毒.     

3种杀菌剂及其复配剂对斑马鱼的急性毒性

采用"半静态法"测定了3种农药及其复配剂对斑马鱼的24 h、48 h、72 h和96 h急性毒性,根据我国《化学农药环境安全评价实验准则》中毒性等级划分标准来划分它们对斑马鱼的毒性等级,发现35%精甲霜灵悬浮种衣剂的24 h、48 h、72 h和96 h-LC_(50)均超过10 a.i.mg·L~(-1),属"低毒"级,而25 g·L~(-1)咯菌腈悬浮种衣剂的24 h、48 h、72 h和96 h-LC_(50)分别为0.704 mg·L~(-1)、0.514 mg·L~(-1)、0.424 mg·L~(-1)、0.262 mg·L~(-1),根据0.100 a.i.mg·L~(-1)LC_(50)(96 h)≤1.00 a.i.mg·L~(-1)划分,属"高毒"级,80%嘧菌酯水分散粒剂的24 h、48 h、72 h和96 h-LC_(50)分别为9.803 mg·L~(-1)、5.175 mg·L~(-1)、4.328 mg·L~(-1)、2.326 mg·L~(-1),根据1.00 a.i.mg·L~(-1)LC_(50)(96 h)≤10.00 a.i.mg·L~(-1)划分,属于"中毒"级。11%精甲霜灵-咯菌腈-嘧菌酯悬浮种衣剂的24 h、48 h、72 h和96 h-LC_(50)分别为2.267 mg·L~(-1)、2.073 mg·L~(-1)、1.620 mg·L~(-1)、1.280 mg·L~(-1),根据1.00 a.i.mg·L~(-1)LC_(50)(96 h)≤10.00 a.i.mg·L~(-1)划分,属于"中毒",虽然11%精甲霜灵-咯菌腈-嘧菌酯悬浮种衣剂和80%嘧菌酯水分散粒剂同属"中毒",但比较具体数值,发现11%精甲霜灵-咯菌腈-嘧菌酯悬浮种衣剂毒性相对更大,原因是其中含有"高毒"的咯菌腈。     

甲基对硫磷降解菌DLL-1的分离、鉴定及降解性研究

从长期施用甲基对硫磷的污染土壤中分离到一株能以甲基对硫磷为唯一碳源生长且能将其完全矿化的细菌 Ｄ Ｌ Ｌ－ １ ,经鉴定,为邻单胞菌（ Ｐｌｅｓｉｏｍｏｎａｓ ｓｐ ．） ．该菌株３ ｈ 内对５０ ｍｇ／ Ｌ甲基对硫磷的降解率为９３ ％ ,２４ｈ 内对５０ ｍｇ／ Ｌ甲基对硫磷的降解率为９５ ％ 以上．在葡萄糖铵盐培养基中, Ｄ Ｌ Ｌ１ 对甲基对硫磷的耐受浓度和降解速度均增大．降解曲线表明延滞期内,菌体依靠上一生长阶段分泌的酶类对甲基对硫磷进行降解,一旦菌体开始生长,则检测不到中间代谢产物对硝基苯酚的存在．生长情况和粗酶液试验均显示 Ｄ Ｌ１ 优良的降解性状     

氰戊菊酯对斑马鱼和稀有鮈鲫不同生命阶段的毒性效应

为探明氰戊菊酯对鱼类不同生命阶段的毒性效应,以斑马鱼和稀有鮈鲫为测试生物,评价了氰戊菊酯对斑马鱼和稀有鮈鲫不同生命阶段的急性毒性差异。研究发现,氰戊菊酯对斑马鱼和稀有鮈鲫胚胎的96 h-LC50值分别为0.901(0.664~1.22)和0.636(0.233~1.74)mg·L~(-1)。氰戊菊酯对稀有鮈鲫胚胎孵化有明显的促进作用,染毒48 h后,0.188和0.375 mg·L~(-1)氰戊菊酯对稀有鮈鲫胚胎的孵化率分别为88.9%和100%。氰戊菊酯对斑马鱼仔鱼、幼鱼和成鱼的96 h-LC50值分别为0.00340、0.0183、0.00487 mg·L~(-1),氰戊菊酯对稀有鮈鲫仔鱼、幼鱼和成鱼的96 h-LC50值分别为0.0520、0.00277、0.00345 mg·L~(-1)。因此,氰戊菊酯对斑马鱼不同生命阶段的毒性从高到低顺序依次为:仔鱼成鱼幼鱼胚胎,氰戊菊酯对稀有鮈鲫胚胎、仔鱼、幼鱼和成鱼的毒性为幼鱼成鱼仔鱼胚胎。试验结果表明,斑马鱼仔鱼对氰戊菊酯的敏感性高于稀有鮈鲫相应的生命阶段,相对于斑马鱼,稀有鮈鲫胚胎、幼鱼以及成鱼对氰戊菊酯的毒性作用更为敏感,说明氰戊菊酯对斑马鱼和稀有鮈鲫不同生命阶段的毒性效应差异较大。     

Larvicidal potential of Nerium indicum and Thuja oriertelis extracts against malaria and Japanese encephalitis vector

Ethanolic and acetone extracts of Nerium indicum and Thuja orientelis have been studied against III instar larvae of Anopheles stephensi and Culex quinquefasciatus. Ethanolic extract of N. indicum is found more effective than its acetone extract against anopheline larvae with LC50 values of 185.99 and 148.05 ppm for former and 229.28 and 149.43 ppm for the later after 24 and 48 hrs of exposure. The acetone extract with LC50 values of 209.00 and 155.97 ppm is more effective in case of culicine larvae than its ethanolic extract with LC50 494.07 and 194.49 ppm after 24 and 48 hours of treatment. Ethanolic extract of T. orientelis is more effective against both the larval species with LC50 values of 13.10 and 9.02 ppm after 24 and 48 hours for anopheline and 22.74 and 16.72 ppm against culicine larvae. The acetone extract showed LC50 values of 200.87 and 127.53 ppm against anopheline and 69.03 and 51.14 ppm against culicine larvae. Thus ethanolic extract of T. orientelis is an ideal potential larvicide for both types of mosquito larvae.     

多效唑对水生生物的急性毒性评价研究

本文以斜生栅藻、大型水蚤和草鱼为试验生物,研究植物生长调节剂多效唑对水生生物的急性毒性效应。多效唑对斜生栅藻EC_(50)-96h为20.62mg/l;对大型水蚤LC_(50)-48h为21.86mg/h;对草鱼苗静态生物检测结果为LC_(50)—120h 16.33mg/l,流水生物检测结果为LC_(50)-96h 14.36mg/l,LC_(50)-120h 9.13mg/l。经多效唑处理后,藻的细胞形态也发生明显改变。根据农药的实验室毒性评价划分标准,多效唑对三种生物的毒性均属低毒;田间安全性预评价的结果也表明其毒性为低毒,故认为多效唑是一种对水生生物危害较小的农药。但其慢性毒性及长期积累效应,尚有待进一步研究。     

Haematotoxic effect of linear alkyl benzene sulphonate (LAS) in fish,Heteropneustes fossilis

It was observed that clotting time decreased with the increased concentrations of LAS. However, the decrease was more pronounced at LC50 for 24 h and at the end of 96 h LC50, it was very close to control values.     

Electrochemical determination of methyl parathion using a modified electrode

Electrochemical studies of pesticides using various electrode systems attain prominence in recent years because of their application in trace determinations. Cyclic voltammetric studies of methyl parathion on a glassy carbon electrode at various pH in 50% aqueous ethanol medium were carried out. Influence of pH led to the selection of pH 1.0 as the best pH for the electroanalysis of methyl parathion. The number of electrons transferred was determined using controlled potential coulometry. On the basis of the results a probable reduction mechanism was proposed. Cyclic voltammetric studies of methyl parathion using polypyrrole deposited and sodium montmorillonite clay modified electrodes in the presence of cetyl trimethyl ammonium bromide were carried out. The clay-modified electrode and the reduction peak around ?0.2?V were selected for stripping analysis owing to their maximum current response. The experimental parameters were optimized using the differential pulse stripping mode. A calibration plot was made. The determination limit and standard deviations were arrived. The applicability of the method was also verified in a sample soil analysis.     

鱼类肝脏微粒体对于硫代磷酸酯类杀虫剂活化代谢率的种间差异(Species-Related Difference of Liver Microsomes of Fish in Activation of Organothiophosphorus Insecticides)

为了弄清鱼类肝脏微粒体细胞色素P450s(CYPs)对于硫代磷酸酯类杀虫剂活化代谢率的种间差别,选用斑马鱼Brachydanio rerio、麦穗鱼Pseudorasbora parva、剑尾鱼Xiphophorus helleri、篮鳃太阳鱼Leponus macrohirus四种鱼作为受试生物,选用对硫磷、马拉硫磷、毒死蜱三种硫代磷酸酯类杀虫剂作为受试药剂,以外源乙酰胆碱酯酶(AchE)的抑制率为指标,在离体状态下间接测量了杀虫剂活化代谢物的相对生成量.离体试验表明,对于对硫磷,活化代谢物生成量的高低顺序为:斑马鱼、剑尾鱼、麦穗鱼>太阳鱼(p<0.05),最高的麦穗鱼和最低的太阳鱼之间相差10.0倍;对于马拉硫磷和毒死蜱,活化代谢物生成量的高低顺序均为:剑尾鱼>太阳鱼>斑马鱼、麦穗鱼(p<0.05),最高的剑尾鱼和最低的麦穗鱼之间的分别相差66.9和137倍.毒性测定表明,对于对硫磷、马拉硫磷和毒死蜱,四种鱼96hLC50之间的最大差别分别是45、18和77倍.对马拉硫磷而言,96hLC50的种间差异特征与活化代谢物生成量的种间差异特征比较吻合,而对于对硫磷和毒死蜱而言,两者之间的吻合度较低.研究证实了肝脏CYP在活化硫代磷酸酯杀虫剂方面具有明显的种间差异,同时也证实仅以活化代谢物的离体生成量这一指标来衡量鱼类对于硫代磷酸酯杀虫剂的敏感性,其结论可能会较大幅度地偏离生测结果.尽管如此,本研究证实在所测的鱼类当中,斑马鱼属于CYP活性较低的鱼种,而这一特性很可能是造成斑马鱼对于硫代磷酸酯杀虫剂的敏感性偏低的重要原因.     

水环境中氯丙嗪污染对鲫鱼和大型蚤的急性毒性效应

氯丙嗪作为一种镇静类兽药被广泛使用,已成为水环境中的一种新型污染物.为检验氯丙嗪对水生生物的生态毒性效应,采用实验室模拟的方法,研究了工业原料药盐酸氯丙嗪对鲫鱼(Carassius auratus)和大型蚤(Daphnia magna)的急性毒性效应.结果表明:氯丙嗪对两种水生生物的毒性效应(致死率、抑制率概率单位)均与其浓度呈显著线性正相关关系(p<0.05),且毒性强度随作用时间的延长而增加;氯丙嗪对鲫鱼的24、48和96h的半致死浓度(LC50)值分别为1.11、0.43和0.32mg·L-1,通过计算求得氯丙嗪对鲫鱼的安全浓度为19.5μg·L-1;氯丙嗪对大型蚤的24h LC50值为0.65mg·L-1,24h EC50值(使50%受试大型蚤活动受抑浓度)为0.57mg·L-1;48h LC50值为0.36mg·L-1,48h EC50值为0.28mg·L-1;对鲫鱼和大型蚤而言,氯丙嗪属极高毒性物质,大型蚤对氯丙嗪的敏感性大于鲫鱼。     

Effects of ammonia, nitrite and nitrate on hemoglobin content and oxygen consumption of freshwater fish, Cyprinus carpio (Linnaeus)

Lethal effects of nitrogenous compounds ammonia, nitrite and nitrate on freshwater fish Cyprinus carpio were studied and the static LC50 values obtained for these 3 toxicants for 24 hr were 0.80 ppb, 171.36 ppm; 1075.10 ppm and continuous flowthrough LC50 values for 24 hr were 0.72 ppb, 154.31 ppm; 967.63 ppm respectively. The fish were exposed to lethal concentrations to study the changes in hematological parameters and the rate of oxygen consumption. During the period of exposure general decline in the content of hemoglobin was observed. Methemoglobin content increased in case of nitrite exposure consequently the hemoglobin levels decreased drastically. It is also observed that rate of oxygen consumption decreased progressively with the increase of toxicant concentration and duration of the exposure.     

Effect of dimecron on the blood parameters of Heteropneustes fossilis

The effects of an organophosphate insecticide. dimecron. has been studied on certain haematological parameters, viz., haemoglobin concentration, RBC number, haematocrit, O2 carrying capacity of blood, etc. of Heteropneustes fossilis following exposures to the LC50 for 24 h and 96 h and 1/10 and 1/50 parts of 96 h LC50 for 90 days. There was a significant decrease in the Hb%, RBC number, HCt% and O2 carrying capcity of blood. But, there was significant increase in the MCH and MCV values following both acute and chronic exposures. The results indicate possible induction of anaemia in the exposed fish.     

Acute toxicity of copper sulphate to fresh water prawns

Fresh water prawns, Macrobrachium lamarrei and Macrobrachium dayanum (Crustacea-Decapoda) were subjected to static bioassay tests to ascertain the LC50 values of copper sulphate. The 24, 48, 72 and 96 hr LC50 values of copper sulphate for M. lamarrei were 0.38, 0.361, 0.343 and 0.300 mg/l and for M. dayanum were 1.634, 0.988, 0.532 and 0.418 mg/l respectively. Behavioral responses and LC50 values indicate that M. lamarrei were more sensitive to copper sulphate than M. dayanum.     

In vitro and in vivo inhibition of Ca2+-Mg2+-ATPase activity by cadmium in post larvae of Penaeus monodon

Ca²⁺-Mg²⁺-ATPase is a membrane-bound enzyme and is responsible for regulating cytosolic free calcium. In vitro and in vivo effects of cadmium were studied on Ca²⁺-Mg²⁺-ATPase activity in plasma membrane/mitochondrial fraction of Penaeus monodon post larvae. In vitro studies revealed a concentration-dependent decrease in enzyme activity with an IC₅₀ value of 11.02?µM. In vivo experiments were conducted by exposing the post larvae to 1/10th (0.12?ppm) and 1/5th (0.24?ppm) of LC₅₀ values of cadmium for 30 days. Both ATPase activity and metal accumulation were estimated in post larvae exposed to 0.12 and 0.24?ppm of cadmium at different intervals of 24?h, 48?h, 96?h, 10 days and 30 days. ATPase activity showed a gradual decrease in post larvae on exposure to both the sub-lethal concentrations with respect to their controls and the decrease was significant (p?相似文献   

不同硬度条件下Cd~(2+)和Cu~(2+)对稀有鮈鲫的急性毒性

为研究水体硬度对稀有鮈鲫Cd~(2+)和Cu~(2+)毒性效应的影响,开展了96 h急性毒性试验。试验结果发现,当水体硬度(以CaCO_3计,下同)为50 mg·L~(-1)、250 mg·L~(-1)、450 mg·L~(-1)时,Cd~(2+)对稀有鮈鲫的96 h半数致死浓度(96 h-LC50)分别为4.30 mg·L-1、12.06 mg·L~(-1)、19.99 mg·L~(-1),对应的安全浓度(SC)依次为0.430 mg·L~(-1)、1.206 mg·L~(-1)、1.999 mg·L~(-1);Cu~(2+)对稀有鮈鲫的96h-LC50分别为0.046 mg·L-1、0.148 mg·L~(-1)、0.228 mg·L~(-1),对应的SC依次为0.0046 mg·L~(-1)、0.0148 mg·L~(-1)、0.0228 mg·L~(-1)。计算得到Cd~(2+)对稀有鮈鲫急性毒性与水体硬度的拟合方程为ln 96 h-LC50=0.687 ln H~(-1).243(r=0.998);Cu~(2+)对稀有鮈鲫急性毒性与水体硬度的拟合方程为ln 96 h-LC50=0.727 ln H-5.923(r=0.999),Cd~(2+)和Cu~(2+)对稀有鮈鲫的硬度斜率分别为0.687和0.727。这些结果表明,水体硬度可有效降低Cd~(2+)和Cu~(2+)对稀有鮈鲫的急性毒性,且稀有鮈鲫的硬度斜率与其他物种差异较大。在评估不同硬度水体下Cd~(2+)和Cu~(2+)的生物毒性及其生态风险时,应根据测试物种特异的硬度斜率而定。     

Acute toxicity evaluation of copper,arsenic and HCH to paddy field crab,Paratelphusa hydrodromus (Herb.)

Routine static tests were conducted for determining the median lethal tolerance limit of paddy field crab, Paratelphusa hydrodromus exposed to Copper, Arsenic and HCH at different time intervals of 24, 48, 72 and 96 hour. The LC50 values for Copper came to be 28.00, 22.00, 18.20 and 15.70 ppm; Arsenic 136.00, 128.00, 121.500 and 114.00 ppm and HCH 10.00, 8.80, 7.00 and 6.00 ppm, respectively. The safe concentration, application factor and safe application rate were also calculated. They were for, Copper: 5.56, 1.59 and 3.26 ppm, Arsenic: 38.53, 11.40 and 76.00 and HCH : 4.07, 0.06 and 1.28 ppm. Animals exposed to different concentrations of test chemicals (Copper, Arsenic and HCH) showed prominent behavioural/morphological alterations viz., coughing, redness on the ventral side, paralysis and disorientation in scaphognathite activity. Animals exposed to high concentrations showed an avoidance behaviour by keeping away from the direct contact with the toxic solution either by climbing on the wall of aquarium or by mounting over the weak individual and forming a type of pyramid.     

DLL-1菌对甲基对硫磷农药的降解作用及其降解机理

研究了假单胞菌 (DLL - 1)在水溶液介质中降解甲基对硫磷的性能与影响因素及其降解机理。结果表明 ,当菌体浓度为 10 5个·ml-1时 ,即发生快速的降解作用 ,3h时 ,降解率达 88.5 %。在pH为 5 .0、7.0和 9.0条件下 ,DLL - 1菌均产生对甲基对硫磷农药的高效降解作用。采用气相色谱 -质谱联用技术与离子色谱法 ,测定了DLL - 1菌 -甲基对硫磷作用过程产生的中间产物和最终产物 ,表明对硝基苯酚为主要中间产物 ,且DLL - 1菌能将其进一步降解为NO2 -和NO3 -。