毒斯乐对蚯蚓的急性毒性试验

采用滤纸接触法和自然土壤法研究了毒斯乐对自然蚯蚓的急性毒性。结果表明,用滤纸接触法测得毒斯乐对蚯蚓的LC50为0.154 g/L,自然土壤法测得毒斯乐对蚯蚓的LC50为1.29 g/L,自然土壤法中毒斯乐对蚯蚓的毒性相对较低。     

椭圆真星介的盐度与温度耐受性研究

研究了采自西藏绒马温泉的椭圆真星介（Eucypris elliptica Baird）在（25±1）℃下对NaCl的耐受性和在盐度S=0.37g/L下的温度耐受性。结果表明,椭圆真星介6h的半致死盐度LC50为32.14g/L（95%置信区间为21.66～42.62g/L）;12h的半致死盐度LC50为17.04g/L（95%置信区间为16.94～17.14g/L）;6h的高温半致死温度LT50为39.3℃（95%置信区间为38.7～40.0℃）;24h的高温半致死温度LT50为36.1℃（95%置信区间为35.6～36.6℃）。6h时,在26.36、32.00g/L的盐度水平下,椭圆真星介全部昏迷;24h时,在17.89、21.72、26.36、32.00g/L的盐度水平下,也全部昏迷。12h时,在42℃的温度水平下全部昏迷。野外采样结果表明,椭圆真星介能在6‰～22‰的盐度和32℃的温泉环境下正常存活,并且椭圆真星介对NaSO4＋MgSO4与NaCl的耐受性不同。     

几种杀虫剂对青杨楔天牛的毒力测定

为筛选有效防治青杨楔天牛(Saperda populnea L.)虫害的药剂及方法,采用点滴法与点涂虫瘿法测定了6种农药对其成虫的毒力,结果表明,活性最高的是氯氰菊酯,采用点滴法和点涂虫瘿法处理后其LC50分别为0.002 55 mg.L-1和0.024 76 mg.L-1;其次是甲氰聚酯,其LC50分别为0.005 51 mg.L-1和0.094 06 mg.L-1;阿维菌素LC50分别为0.012 68 mg.L-1和0.061 56 mg.L-1;毒死蜱LC50分别为0.056 31 mg.L-1和0.084 31 mg.L-1;灭幼脲LC50分别为0.079 14 mg.L-1和0.100 00 mg.L-1;除虫脲LC50分别为0.260 00 mg.L-1和0.400 00mg.L-1。     

湖南现行家蚕品种资源对氟化物的抗性

于4龄期分别采用150、300、600、1 200、2 400mg/kgNaF的2倍稀释液对湖南省现行家蚕22个品种资源进行添毒试验,通过机率值法和最小二乘法,分别得出NaF对各品种的毒力回归方程和对家蚕品种资源的半致死量(LC50).结果表明:湖南省现行家蚕品种间的LC50差异较大,抗性强品种1514、秋白B、853...     

Importance of dose metrics for lethal and sublethal sediment metal toxicity in the oligochaete worm Lumbriculus variegatus

Background, Aims, and Scope  There is an increasing demand for controlled toxicity tests to predict biological effects related to sediment metal contamination. In this context, questions of metal-specific factors, sensitivity of toxicity endpoints, and variability in exposure duration arise. In addition, the choice of the dose metrics for responses is equally important and is related to the applicability of the concept of critical body residue (CBR) in exposure assessments, as well as being the main focus of this study. Methods  Experiments were conducted to assess toxicity of Cd, Cr, Cu and Pb to the oligochaete worm Lumbriculus variegatus with the aim of determining CBRs for two response metrics. Mortality and feeding activity of worms exposed to sediment-spiked metals were used as end-points in connection with residue analyses from both the organisms and the surrounding media. Results  LC50 values were 0.3, 1.4, 5.2, and 6.7 mg/L (from 4.7 μmol/L to 128.0 μmol/L), and the order of toxicity, from most toxic to least toxic, was Cu > Cd > Pb>Cr. By relating toxicity to body residue, variability in toxicity among the metals decreased and the order of toxicity was altered. The highest lethal residue value was obtained for Cu (10.8 mmol/kg) and the lowest was obtained for Cd (2.3 mmol/kg). In the 10-d sublethal test, both time and metal exposure were an important source of variation in the feeding activity of worms. The significant treatment effects were observed from worms exposed to Cd or Pb, with the controls yielding the highest feeding rate. However, quantitative changes in the measured endpoint did not correlate with the exposure concentrations or body residues, which remained an order of magnitude lower than in the acute exposures. Discussion  Both response metrics were able to detect a toxic effect of the metals. However, the ranking of metal toxicity was dependant on the choice of the dose metric used. An attempt to form a causal mortality-mediated link between tissue residues and metal toxicity was successful in water-only exposures. The results also indicated that egestion rate was a sensitive toxicity end point for predicting the effects of sediment contamination. Conclusions  By relating the biological response with the tissue metal residues, toxicity data was comparable to both environmental media as well as different response metrics and time scales. The results also revealed the importance of metal toxicity ranking on a molar basis and, furthermore, a direct link to the CBR concept was established. Recommendations and Perspectives  There is a growing demand for methods to assess the effects of contaminated sediments to benthic fauna and whole aquatic ecosystems. Such information is needed for sediment quality guidelines that are currently being developed in many countries and remediation processes. The use of body residues as a dose metric in metal toxicity studies may help to overcome difficulties related to bioavailability issues commonly faced in sediment toxicity studies. ESS-Submission Editor: Prof. Dr. Henner Hollert (henner.hollert@bio5.rwth-aachen.de)     

Detection of Diarrheic Shellfish Poisoning and Azaspiracid Toxins in Moroccan Mussels: Comparison of the LC-MS Method with the Commercial Immunoassay Kit

Diarrheic shellfish poisoning (DSP) is a recurrent gastrointestinal illness in Morocco, resulting from consumption of contaminated shellfish. In order to develop a rapid and reliable technique for toxins detection, we have compared the results obtained by a commercial immunoassay-“DSP-Check” kit” with those obtained by LC-MS. Both techniques are capable of detecting the toxins in the whole flesh extract which was subjected to prior alkaline hydrolysis in order to detect simultaneously the esterified and non esterified toxin forms. The LC-MS method was found to be able to detect a high level of okadaic acid (OA), low level of dinophysistoxin-2 (DTX2), and surprisingly, traces of azaspiracids 2 (AZA2) in mussels. This is the first report of a survey carried out for azaspiracid (AZP) contamination of shellfish harvested in the coastal areas of Morocco. The “DSP-Check” kit was found to detect quantitatively DSP toxins in all contaminated samples containing only OA, provided that the parent toxins were within the range of detection and was not in an ester form. A good correlation was observed between the two methods when appropriate dilutions were performed. The immunoassay kit appeared to be more sensitive, specific and faster than LC-MS for determination of DSP in total shellfish extract.     

对苯二胺对泥鳅的急性毒性及安全评价

研究对苯二胺对泥鳅的急性毒性并进行安全性评价。在实验室条件下,以染发剂的主要成分对苯二胺为诱变剂,采用半静水试验法,研究了对苯二胺在不同浓度（0、15、17.85、21.24、25.27和30mg/L）和不同染毒时间（24、48、72和96h）条件下,对泥鳅（Misgurnus angullicaudatus）的急性毒性作用。结果表明：对苯二胺24、48、72和96h的LC50分别是39.40、27.93、23.69和18.78mg/L,安全浓度为4.21mg/L。根据有毒物质对鱼类的急性毒性标准,对苯二     

邻苯二甲酸二丁酯对红鳍笛鲷幼鱼的胁迫效应

为了探讨邻苯二甲酸二丁酯(DBP)对红鳍笛鲷(Lutjanus erythropterus)幼鱼的胁迫效应,于DBP暴露后0、6、12、24、48和96 h时检测红鳍笛鲷鳃、肝和脑组织中超氧化物歧化酶(SOD)、丙二醛(MDA)和乙酰胆碱酯酶(AChE)活性。结果表明,DBP对红鳍笛鲷的24 h、48 h和96 h LC50分别为7.10 mg/L、6.98 mg/L和6.66 mg/L,安全质量浓度为2.04 mg/L。随着浓度增加,鳃组织中的SOD酶活性表现为先升高后下降,具有明显的时间效应;肝组织中的SOD酶活性在0.5 mg/L和2.0 mg/L浓度组交替表现为升高和降低,与对照组比较有显著性差异(P<0.05);而0.125 mg/L浓度组肝SOD没有明显变化。鳃组织中MDA含量在DBP暴露6 h后显著性增加(P<0.05),之后随时间延长而下降;DBP暴露6 h和12 h后,0.5 mg/L和2.0 mg/L浓度组肝组织中的MDA含量都显著升高(P<0.05),之后随时间延长MDA含量下降并趋于稳定。与对照组比较,DBP暴露48 h后,红鳍笛鲷脑组织中AChE酶活性显著升高(P<0.01),96 ...