焦性没食子酸对3种不同水生生物的毒性作用

目的研究焦性没食子酸对水生生物的毒性作用。方法以蛋白核小球藻(Chlorella pyrenoidosaChick)、斜生栅藻(Scenedesmus obliquus)和多刺裸腹溞(Moina macrocopa)作为受试对象,探讨不同浓度的焦性没食子酸(pyrogallol)的急性毒性效应。结果随焦性没食子酸浓度的增加藻细胞密度和溞数量明显下降,呈现剂量-效应关系;焦性没食子酸对蛋白核小球藻和斜生栅藻半抑制效应浓度(EC50)分别为19.7mg/L和19.8mg/L,对多刺裸腹溞24h和48h半抑制效应浓度分别为18.25mg/L和13.96mg/L。结论焦性没食子酸对蛋白核小球藻、斜生栅藻和多刺裸腹溞均属于中毒。     

应用大型水蚤对几种农药污染饮用水毒性的快速检测

目的 了解采用大型水蚤检测农药污染饮用水的可行性，为建立水质综合毒性评价方法提供依据。方法 采用大型水蚤的急性毒性试验方法检测饮用水的毒性，用SPSS12．0统计分析大型水蚤的LC50.结果 大型水蚤能够灵敏检测饮用水农药污染，在浓度达到微克时，仍然有反应；部分被检测农药的8h LC50与24h和48h结果相近，可以近似用来代替24h和48h的毒性测试结果，缩短毒性测试时间。结论大型水蚤的急性毒性测试方法是一种简便、快速、灵敏和价廉的方法，可以用来对饮用水的部分农药污染进行快速检测。     

三氯化锑对泥鳅的毒性效应

为研究三氯化锑对泥鳅的急性毒性(96h内)和遗传毒性效应,将180尾泥鳅分别暴露于25.12、43.65、75.86、131.83mg/L三氯化锑溶液连续96 h,每组30尾,分别于24、48、96 h计算死亡率及相应的半数致死浓度(LC50)以及安全浓度(SC);将90尾泥鳅分别暴露于10、20、30、40 mg/L三氯化锑溶液96 h,每24 h取尾血,计算微核率。两试验均设立溶剂对照(0.2%乙醇)组和空白对照组。结果显示,三氯化锑对泥鳅的24、48、96h LC50分别为111.686、87.983、60.954mg/L,SC为16.384 mg/L。与对照组比较,各浓度三氯化锑暴露组泥鳅外周血红细胞的微核率均上升,除10 mg/L三氯化锑暴露24 h组外,差异均有统计学意义(P0.05,P0.01)。提示三氯化锑对泥鳅具有急性毒性和遗传毒性。     

水生生物在评价微生物水质改良剂的生态毒性中的应用

目的 探讨微生物型水质改良剂对斑马鱼和大型溞的急性毒性,为其安全使用提供依据.方法 将斑马鱼、大型溞分别暴露于不同浓度的水质改良剂稀释液中48 h,用概率单位图解法计算受试物对两种生物24 h、48 h的半数致死浓度(LC50).结果 受试物对斑马鱼24、48 h的LC50分别为15.66％和9.85％,对大型溞24、48 h的LC50分别为6.30％和3.13％.结论 微生物水质改良剂对斑马鱼及大型溞的急性毒性作用较小,但对其慢性毒性仍需进行研究.     

对氯硝基苯和2,4-二硝基氯苯对锦鲤鱼急性毒性作用

目的研究水体中对氯硝基苯（P-NCB）和2,4-二硝基氯苯（DNCB）对锦鲤鱼的急性毒性作用。方法以锦鲤鱼为试验生物。在预试验中,设5个P-NCB染毒组,浓度分别为40、30、20、10、5mg/L;设6个DNCB染毒组,浓度分别为2、1、0.7、0.5、0.3、0.1mg/L,筛选出24h100%致死浓度（24h LC100）和96h最大耐受浓度（96hLC0）。根据预试验的结果,在24h LC100和96hLC0之间,按等对数间距设5个染毒组,并设置2个平行样、空白对照组和助溶剂对照组（乙醇）进行急性毒性试验。按照《鱼类急性毒性实验的毒性分级标准》进行评价。采用平均致死量法（寇氏法）计算P-NCB和DNCB的LC50。结果预试验结果表明,P-NCB的24h LC100和96h LC0分别为40、5mg/L,DNCB的24h LC100和96h LC0分别为1.0、0.5mg/L。急性毒性试验中,P-NCB染毒组浓度分别为40、23.71、14.13、8.41、5mg/L;DNCB染毒组浓度分别为1.0、0.84、0.706、0.594、0.5mg/L。在急性毒性试验过程中,助溶剂对照组和空白对照组均未发生鱼中毒症状和死亡现象。各染毒组的鱼被投入试验液后均出现急速游动,向上跳跃,呼吸频率加快的现象。40、23.71mg/LP-NCB染毒组的鱼逐渐失去平衡,丧失游泳能力,最后出现麻痹状态,侧卧于水面;1.0、0.84mg/LDNCB染毒组的鱼除有上述表现外,有的还出现竖立游行,身体抽搐等现象。14.13、8.41、5mg/LP-NCB染毒组和0.706、0.594、0.5mg/LDNCB染毒组的鱼基本能适应环境,并可以正常游动。P-NCB对锦鲤鱼96h LC50为22.13mg/L,属于高毒物质;DNCB对锦鲤鱼96h LC50为0.692mg/L,属于剧毒物质,且两者的LC50均随着染毒时间的延长而降低。结论P-NCB的毒性弱于DNCB,但其在GB 3838—2002《地表水环境质量标准》中的限值却小于DNCB。因此,水质标准的制订应从化合物的生物毒性、污水的排放标准及其处理水平、饮用水的处理工艺等多方面进行综合考虑。     

饮水氯化消毒副产物氯仿和一溴二氯甲烷对斑马鱼胚胎发育的毒性作用

[目的]研究饮水氯化消毒副产物中主要成分氯仿（CHCl3）和一溴二氯甲烷（BDCM）对斑马鱼（zebrafish,danio rerio）胚胎发育的毒性效应。[方法]采用斑马鱼胚胎发育技术,分别用不同质量浓度的CHCl3和BDCM对受精后Oh（0hpf）和24h（24hpf）的斑马鱼胚胎进行染毒。在染毒后4、8、12、16、24、48h进行胚胎活体摄影,并分别计算CHCl3及BDCM对斑马鱼胚胎染毒后24h和48h的半数致死浓度（LC50）和半数致畸效应浓度（EC50）。[结果]0hpf斑马鱼胚胎CHCl3和BDCM的LC50分别为0．814mg／L和1．945mg／L。24hpf胚胎CHCl3和BDCM染毒的LC50分别为1．076mg／L和2．676mg／L。斑马鱼胚胎对CHCl3最敏感的致畸毒理学终点为48h无心律和心胞囊肿,其0hpf斑马鱼胚胎试验发现,48h无心律和心胞囊肿的EC50分别为0．39mg／L和0．35mg／L;而24hpf斑马鱼胚胎试验发现,48h无心律和心胞囊肿的EC50分别为0．77mg／L和0．63mg／L。对BDCM最敏感的致畸毒理学终点也是48h无心律和心胞囊肿,与CHCl3相似,但在0hpf斑马鱼胚胎试验中上述两项指标的EC50分别为0．81mg／L和0．72mg／L,在24hpf斑马鱼胚胎试验中分别为3．52mg／L和3．17mg／L。[结论]CHCl,和BDCM对0hpf斑马鱼胚胎的毒性均大于对24hpf胚胎的毒性;CHCl3的发育毒性大于BDCM。斑马鱼胚胎对CHCl3和BDCM致畸效应最敏感的终点为48h无心律和心胞囊肿。     

产毒节菱孢培养物对大型溞的毒性研究

本文以国际标准实验生物大型溞做为实验动物研究了节菱孢毒性培养物的毒性。结果表明节菱孢毒性培养物对大型溞的EC_(50)值分别为29.07mg/L(24h);20.57mg/L(48h);7.53mg/L(96h)。LC_(50)值分别为38.07mg/ (24h);24.37mg/L(48h);10.67mg/L(96h)。     

氟硒联合毒性作用的研究

研究了氟硒对水生物大型水蚤和挠足动物及哺乳动物小鼠的联合毒性。在本实验条件下,NaF的毒性半数致死浓度LC_(50)(48h)对大型水蚤为390mg/L,对挠足动物为295mg/L,对小鼠半数致死量LD_(50)为260mg/L;Na_2SeO_3的毒性LC_(50)(48h)对大型水蚤为1.6mg/L,对挠足动物为15.3mg/L,对小鼠的LD_(50)为33.6mg/kg,这些结果呈一定的规律,且均是亚硒酸钠的毒性远大于氟化钠。氟硒联合作用水生物实验采用毒性单位法及相加指数法进行评价,动物实验采用Q值进行评价,结果显示氟硒配比浓度(剂量组合)低时或低硒高氟时的联合作用以拮抗为主,特别是对大型水蚤氟硒比为10:1时拮抗作用最强;高硒高氟时,尤其对小鼠的联合急性毒性以协同作用为主。     

亚麻酸在富营养化水体中对镉生物有效性的影响北大核心CSCD

目的探讨重金属镉(Cd)在有抑藻剂亚麻酸存在时对浮游藻类的生物有效性。方法分别用不同浓度Cd^(2+)(0.10、0.20、0.30和0.40 mg/L)单独以及与亚麻酸(0.01 mL/L)组合对斜生栅藻(Scenedesmus obliquus)和铜绿微囊藻(Microcystis aeruginosa)进行处理,测定不同处理条件对斜生栅藻和铜绿微囊藻的抑制作用以及对藻细胞吸附和吸收镉离子作用的影响。结果单独镉和单独亚麻酸在各实验浓度下对铜绿微囊藻和斜生栅藻均有一定抑制作用,对铜绿微囊藻的抑制作用更强,0.10和0.40 mg/L Cd^(2+)在第96 h对铜绿微囊藻的抑制率分别达到42.17%和67.42%,单独0.01 mL/L亚麻酸在第96 h对铜绿微囊藻的抑制率为39.33%,但当与镉复合存在时,对铜绿微囊藻和斜生栅藻的抑制效应均没有显著性改变。有亚麻酸存在时,斜生栅藻与铜绿微囊藻对镉的吸收及吸附量均显著性减少(P<0.05)。结论脂肪酸的羧基可能对镉离子有轻度螯合作用,从而降低了重金属镉的毒性,也减少了镉被藻细胞的吸附或吸收。     

亚麻酸在富营养化水体中对镉生物有效性的影响

目的探讨重金属镉(Cd)在有抑藻剂亚麻酸存在时对浮游藻类的生物有效性。方法分别用不同浓度Cd~(2+)(0.10、0.20、0.30和0.40 mg/L)单独以及与亚麻酸(0.01 mL/L)组合对斜生栅藻(Scenedesmus obliquus)和铜绿微囊藻(Microcystis aeruginosa)进行处理,测定不同处理条件对斜生栅藻和铜绿微囊藻的抑制作用以及对藻细胞吸附和吸收镉离子作用的影响。结果单独镉和单独亚麻酸在各实验浓度下对铜绿微囊藻和斜生栅藻均有一定抑制作用,对铜绿微囊藻的抑制作用更强,0.10和0.40 mg/L Cd~(2+)在第96 h对铜绿微囊藻的抑制率分别达到42.17%和67.42%,单独0.01 mL/L亚麻酸在第96 h对铜绿微囊藻的抑制率为39.33%,但当与镉复合存在时,对铜绿微囊藻和斜生栅藻的抑制效应均没有显著性改变。有亚麻酸存在时,斜生栅藻与铜绿微囊藻对镉的吸收及吸附量均显著性减少(P0.05)。结论脂肪酸的羧基可能对镉离子有轻度螯合作用,从而降低了重金属镉的毒性,也减少了镉被藻细胞的吸附或吸收。     

铝离子对大型溞的毒性研究

本研究以大型溞为实验生物对铝离子的毒性进行了观察,研究了铝离子对大型溞的快速监测指标(生存和运动试验)及铝离子对潘的长期效应影响(生长和繁殖试验)。结果表明,铝离子对大型溞具有一定的毒性,铝离子浓度越高对溞影响越大。对大型溞EC_(50)值24、48和96小时分别为5.2mg/L、4.3mg/L和0.65mg/L。LC_(50)值24、48和96小时分别为5.6mg/L、4.6mg/L和0.97mg/L。试验三周后溞的体长对照组、0.001 mg/L和0.01 mg/L的浓度组体长分别为3.5mm、3.2mm和3.0mm。对照组平均繁殖量为112.2个幼溞,0.001mg/L繁殖量为89.5个,0.01mg/L繁殖量为69.3个,两个浓度组分别比对照组的繁殖量减少20.2％和38.2％。本研究为建立溞类的实验方法提供了科学依据。     

钛对大型溞(Daphnia magna)的毒性研究

钛对大型溞有一定毒性,其24,48,96 小时半数运动抑制浓度EC_(50)值为6.2,5.1,0.26mg/L。半数死亡浓度LC_(50)值为6.8,6.0,1.5mg/L。明显影响生长,每殖的浓度为0.0001mg/L,本研究为制订水质卫生标准提供水生生物毒理学方面的科学依据。     

Toxicological evaluation of nitrofurazone and furaltadone on Selenastrum capricornutum, Daphnia magna, and Musca domestica

Short-term toxicity of nitrofurans, nitrofurazone, furaltadone tartrate, and furaltadone chlorohydrate, was tested in the laboratory on two freshwater organisms, Selenastrum capricornutum (algae) and Daphnia magna (crustaceans). Toxicity studies with nitrofurazone were also carried out on larval development of the house fly Musca domestica L. Nitrofurazone was invariably the most toxic compound (the 96-hr EC50 of algal species was 1.45 mg/liters; the EC50 values for D. magna were 40.04 and 28.67 mg/liter after 24 and 48 hr, respectively) followed by furaltadone tartrate and furaltadone chlorohydrate. This study provides some evidence of the potential ecotoxicity of nitrofurans, indicating the need for further investigations.     

Aquatic toxicity evaluation of para-methylstyrene

The aquatic toxicity of para-methylstyrene was evaluated in acute toxicity studies using fathead minnows (Pimephales promelas), daphnids (Daphnia magna), and freshwater green algae (Selenastrum capricornutum). Static tests were performed in sealed containers with no headspace to minimize loss of this volatile compound to the atmosphere. Concentrations of para-methylstyrene in test solutions were analyzed by gas chromatography equipped with a purge and trap module and flame ionization detection. Test results are based on mean, measured concentrations. para-Methylstyrene was moderately toxic to fathead minnows, daphnids, and green algae. The 96-h LC(50) and NOEC for fathead minnows were 5.2 and 2.6 mg/L, respectively. The 48-h EC(50) and NOEC for daphnids were 1.3 and 0.81 mg/L, respectively. The 72-h EC(50) and NOEC for green algae were 2.3 and 0.53 mg/L, respectively; these effects were algistatic rather than algicidal. para-Methylstyrene's potential impact on aquatic ecosystems is significantly mitigated by its volatility, an important fate process.     

Acute and chronic toxicity of nickel to a cladoceran (Ceriodaphnia dubia) and an amphipod (Hyalella azteca)

This study evaluated acute and chronic nickel (Ni) toxicity to Ceriodaphnia dubia and Hyalella azteca with the objective of generating information for the development of a biotic ligand model for Ni. Testing with C. dubia was used to evaluate the effect of ambient hardness on Ni toxicity, whereas the larger H. azteca was used to derive lethal body burden information for Ni toxicity. As was expected, acute C. dubia median lethal concentrations (LC50s) for Ni increased with increasing water hardness. The 48-h LC50s were 81, 148, 261, and 400 microg/L at hardnesses of 50, 113, 161, and 253 mg/L (as CaCO3), respectively. Ceriodaphnia dubia was found to be significantly more sensitive in chronic exposures than other species tested (including other daphnids such as Daphnia magna); chronic toxicity was less dependent on hardness than was acute toxicity. Chronic 20% effective concentrations (EC20s) were estimated at <3.8, 4.7, 4.0, and 6.9 microg/L at hardnesses of 50, 113, 161, and 253 mg/L, respectively. Testing with H. azteca resulted in a 96-h LC50 of 3,045 microg/L and a 14-d EC20 of 61 microg/L at a hardness of 98 mg/L (as CaCO3). Survival was more sensitive than was growth in the chronic study with H. azteca. The 20% lethal accumulation effect level based on measured Ni body burdens was 247 nmol/g wet weight.     

Ecological hazard assessment of major veterinary benzimidazoles: acute and chronic toxicities to aquatic microbes and invertebrates

Aquatic toxicities of six benzimidazole-based anthelmintics-namely, albendazole, thiabendazole, flubendazole, febantel, fenbendazole, and oxfendazole-were evaluated with a marine bacterium, Vibrio fischeri, and a freshwater invertebrate, Daphnia magna. Delayed and chronic toxicity tests using D. magna also were conducted for benzimidazoles with high acute toxicity. Vibrio fischeri was greater than 10-fold less sensitive to most of the benzimidazoles tested compared to daphnids. For D. magna, the most acutely toxic anthelmintic compound tested was fenbendazole (48-h median effective concentration [EC50s], 16.5 microg/L), followed by flubendazole (48-h EC50, 66.5 micro/L), albendazole (48-h EC50, 67.9 microg/L), febantel (48-h EC50, 216.5 microg/L), thiabendazole (48-h EC50, 843.6 microg/L), and oxfendazole (48-h EC50, 1,168.4 microg/L). The lipophilicity parameter, log Kow, explained the observed acute D. magna toxicity of the individual benzimidazoles (r = -0.91, p < 0.01). Delayed expression of toxicity observed for 21 d after 96-h exposure to fenbendazole and flubendazole was not notable, which might result from the relatively high elimination constants for the chemicals. With chronic exposure to fenbendazole, D. magna survival, reproduction, and growth were significantly impacted at 1.25 to 4.1 microg/L (p < 0.05). Hazard quotients estimated for fenbendazole, albendazole, flubendazole, and febantel were 2,770, 9.7, 4, and 1.2, respectively, suggesting a need for further investigation and a potential for environmental concerns, particularly with fenbendazole.     

三种农药对挠足动物Nitocra的毒性研究

采用国外新推出的实验生物Nitocra spinipes(挠足动物,美丽猛水蚤属Nitocra的一种)对两种拟菊酯类杀虫剂新农药溴氰菊酯及速灭杀丁以及我国现用的农药杀虫脒进行了毒性测定。获得了24、48及96h的半数活动受抑制浓度EC_50值及半数致死浓度LC_50值。其毒性大小顺序:溴氰菊酯>速灭杀丁>杀虫脒。     

Aquatic toxicity of triclosan

The aquatic toxicity of triclosan (TCS), a chlorinated biphenyl ether used as an antimicrobial in consumer products, was studied with activated-sludge microorganisms, algae, invertebrates, and fish. Triclosan, a compound used for inhibiting microbial growth, was not toxic to wastewater microorganisms at concentrations less than aqueous solubility. The 48-h Daphnia magna median effective concentration (EC50) was 390 microg/L and the 96-h median lethal concentration values for Pimephales promelas and Lepomis macrochirus were 260 and 370 microg/L, respectively. A no-observed-effect concentration (NOEC) and lowest-observed-effect concentration of 34.1 microg/L and 71.3 microg/L, respectively, were determined with an early life-stage toxicity test with Oncorhynchus mykiss. During a 96-h Scenedesmus study, the 96-h biomass EC50 was 1.4 microg/L and the 96-h NOEC was 0.69 microg/L. Other algae and Lemna also were investigated. Bioconcentration was assessed with Danio rerio. The average TCS accumulation factor over the five-week test period was 4,157 at 3 microg/L and 2,532 at 30 microg/L. Algae were determined to be the most susceptible organisms. Toxicity of a TCS-containing wastewater secondary effluent to P. promelas and Ceriodaphnia was evaluated and no observed differences in toxicity between control and TCS-treated laboratory units were detected. The neutral form of TCS was determined to be associated with toxic effects. Ionization and sorption will mitigate those effects in the aquatic compartment.     

Toxicity of cypermethrin on growth, pigments, and superoxide dismutase of Scenedesmus obliquus

Cypermethrin is a synthetic pyrethroid that is particularly toxic to crustaceans. It is therefore applied as a chemotherapeutant in farms for the treatment of pests. The effective concentrations of cypermethrin on the inhibition of Scenedesmus obliquus growth at 96 h (96 h EC50) were determined to be 50, 100, 150, 200, and 250 mg/L. Algal growth, pigment fractions, and the activity of superoxide dismutase (SOD) in the algal cells were measured in the exponential phase after exposure to cypermethrin. The results show that higher concentration of cypermethrin is inhibitory for growth and other metabolic activities and the 96 h EC50 of cypermethrin to S. obliquus is 112+/-9 mg/L; the potential application of SOD activity in S. obliquus as a sensitive biomarker for cypermethrin exposure is also discussed.