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1.
Sensitivity of green and blue-green algae to methyl tert-butyl ether   总被引:1,自引:0,他引:1  
The toxicity of methyl tert-butyl ether (MTBE) to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high (2.00×104 mg/L) to low (2 mg/L). The results showed that the toxicity was low when the concentration of MTBE was in the range 1.00×104-2.00×104 mg/L (the greatest inhibition of growth-rate was 70%-71%, occurred during the day 1-5). Low concentrations (2-500 mg/L) stimulated algal growth up to the greatest effect of 85%-200% w...  相似文献   

2.
铅污染对菱幼苗SOD、POD及叶细胞亚显微结构的影响   总被引:2,自引:1,他引:1       下载免费PDF全文
不同浓度Pb2+溶液处理菱(Trapa bicornis Osbeck)幼苗后,考察了菱幼苗的超氧化物歧化酶(SOD)、过氧化物酶(POD)以及叶细胞亚显微结构出现的变化,并初步探讨了Pb2+的毒性机理.结果表明,SOD的活性与铅离子浓度(5~20mg/L)表现出明显的剂量-效应关系, Pb2+浓度愈大,毒害程度愈深.POD活性在较低浓度(5,10mg/L)作用下,持续升高;在较高浓度(15,20mg/L)下,其活性出现先上升后下降的趋势.电子显微镜观察发现,在20mg/L Pb2+溶液处理7d后,叶细胞的叶绿体基粒数目减少,基粒片层解体,叶绿体双层膜断裂;线粒体、高尔基体、内质网等解体消失;细胞核的染色质与核质遭到破坏,核膜破裂.同样处理条件的叶片组织总DNA电泳显示,DNA完全断裂呈现弥散状,提示Pb2+毒害所致细胞死亡有别于细胞程序性死亡. Pb2+对菱的毒害是多途径综合作用的结果.  相似文献   

3.
印染废水中的壬基酚聚氧乙烯醚(nonylphnol polyethylene ether, NPEO)在生化处理过程中会产生雌激素活性更强的壬基酚(NP)等中间产物,导致处理后印染废水内分泌干扰毒性升高.为探索以NPEO和NP为降解靶点进行菌群生物强化脱毒的可行性,分别以NPEO和NP驯化富集印染活性污泥,并将得到的降解菌群以单独和组合投加方式进行生物强化试验,考察强化控毒效果.结果表明:(1)NPEO降解菌群(NPEB)和NP降解菌群(NPB)中的优势菌均为Proteobacteria,二者对10 mg/L NPEO和NP的48 h去除率均高于98%.(2)单独或组合投加5 mg/L的NPEB和NPB至混合液悬浮固体浓度(MLSS)为500 mg/L的活性污泥体系,均能显著提升活性污泥对不同浓度(10和1 mg/L) NPEO的降解性能,大幅缩短NPEO降解过程中雌激素活性的变化周期,并使体系的雌激素活性维持在较低水平.(3)当降解体系中加入1 000 mg/L葡萄糖作为额外碳源时,NPB的强化性能被完全抑制,而NPEB在降解性能受抑的情况下仍能增强活性污泥的NPEO降解速率并缩短控...  相似文献   

4.
针对膜生物反应器(membrane bioreactor,MBR)处理城市污水的后续次氯酸钠消毒,分别开展了不同氯的投加剂量对指示微生物(总大肠菌群和粪大肠菌群)的灭活效果、消毒副产物(disinfection by-products,DBPs)生成量以及消毒后出水发光菌急性毒性研究.结果表明,在工程应用中MBR处理工...  相似文献   

5.
杨蕾  李英华  李海波  苏菲 《中国环境科学》2019,39(11):4812-4822
应用超高效液相色谱-质谱技术(UPLC-MS),基于代谢组学方法,筛选不同进水有机负荷下地下渗滤系统潜在生物标志物.采用偏最小二乘法(PLS-DA)和主成分分析(PCA)模式识别方法对样品进行分型处理,根据模型的变量重要性因子(VIP值)筛选潜在生物标志物,分析代谢产物蕴含的生物学信息,研究代谢通路,通过RDA分析探索代谢产物与环境因子之间的相关性.PLS-DA模型结果表明,当进水有机负荷为250mg/L、400mg/L、500mg/L时,同一高度层代谢产物间存在显著性差异,共筛选出VIP值大于1.5的230种差异代谢物,以有机酸为主;同时也存在一些醇类、酚类等微生物代谢中间产物.此外,微生物代谢产物与模拟土柱高度有显著对应性.在水力负荷为0.14m3/(m2·d),COD污染负荷为400mg/L条件下,3个高度层H2(500mm)、H4(1000mm)、H6(1500mm)筛选出53种VIP值大于1.5的差异代谢物,以酸类、酮类物质为主.RDA分析表明,随着有机负荷波动和剖面高度的变化,代谢产物受到氧化还原环境(ORP)与硝态氮(NO3-)的影响较大,呈负相关.  相似文献   

6.
Bisphenol A (BPA) is the monomer component of polycarbonate plastics and classified as an endocrine disrupting chemical (EDC). The reproductive toxicity of BPA has been extensively studied in mammals; however, relatively little information is available on the immunotoxic responses of fish to BPA. In this study, we investigated the effects of BPA on the immune functions of lymphocytes and macrophages in Carassius auratus. The effects of BPA were compared with those of two natural steroid hormones, estradiol and hydrocortisone. Proliferation of the two types of cells in response to PHA was measured using colorimetric MTT assay. Macrophage respiratory burst stimulated by Con A was measured using chemiluminescence assay. Results showed that BPA (0.054-5.4 mg/L), estradiol (0.0002-2.0 mg/L) and hydrocortisone (5-50 mg/L) significantly induced Carassius auratus lymphocyte proliferation while higher doses of hydrocortisone (500-5000 mg/L) appeared to be inhibitory. BPA (0.005-50 mg/L), estradiol (0.005-800 mg/L) and hydrocortisone (0.005-500 mg/L) markedly enhanced macrophage proliferation, whereas higher doses of BPA (500-1000 mg/L) appeared to inhibit cell proliferation. Furthermore, higher dosage of BPA (50 mg/L) and hydrocortisone (50 and 500 mg/L) suppressed the macrophages respiratory burst while estradiol is stimulative all the doses tested (0.05-500 mg/L). In conclusion, BPA could have immunotoxicity to Carassius auratus and functional changes of lymphocyte and macrophage in Carassius auratus may be different between low and high dosages.  相似文献   

7.
为探讨全氟辛烷磺酸盐(PFOS)产生肺毒性的分子机制,采用细胞计数试剂盒(CCK-8)方法测定不同浓度PFOS对A549细胞活性的影响,并用二代测序方法测定PFOS暴露对A549细胞中miRNAs表达的影响,预测异常表达miRNAs的靶基因.通过生物信息学分析推断靶基因参与的信号通路及潜在的生物学功能.结果显示,低浓度PFOS(<00μmol/L)促进A549细胞增殖,高浓度PFOS抑制细胞增殖.暴露于300μmol/L PFOS中24h的A549细胞中108个miRNAs表达量显著上调,63个miRNAs表达量显著下调.差异表达miRNAs通过Ras、Rap1、HIF-1、ErbB和VEGF等信号通路参与细胞增殖、代谢和发育等生物学过程.这表明PFOS可通过影响细胞增殖和诱发炎症反应对肺造成威胁.  相似文献   

8.
本研究以模式动物斑马鱼(Danio rerio)为受试生物,采用半静态水体暴露的方式研究了不同浓度壬基酚聚氧乙烯醚(NPEO)对斑马鱼雄性成鱼下丘脑-垂体-性腺轴(HPG轴)的影响.结果显示,考察浓度范围内的NPEO暴露可以显著上调斑马鱼脑中GnRH2、GnRHR1、GnRHR2、GnRHR4、FSHβ和LHβ基因,以及性腺中LHR基因的相对表达量.GnRHR和LHR基因表达量对较低浓度NPEO暴露较为敏感,其中GnRHR4和LHR基因表达量在低至0.001mg/L的NPEO暴露下即出现显著上调.0.1和10mg/L NPEO暴露可以显著抑制斑马鱼精巢中CYP17基因的表达量,而10mg/L NPEO暴露则可以显著诱导CYP19a基因的表达量.GnRH相关调控基因表达量的上调,表明NPEO暴露可以诱导下丘脑分泌GnRH,进而刺激垂体分泌GtH.NPEO暴露诱导CYP19a基因的表达,促进了内源雌激素的合成.同时,NPEO通过抑制CYP17表达,可能抑制睾酮(T)的合成,干扰斑马鱼精巢中原有的性激素平衡.斑马鱼精巢内雌激素水平升高负反馈给垂体,刺激垂体分泌促性腺激素.由此表明,考察浓度范围内(0.001~10mg/L)的NPEO的暴露可以影响雄性斑马鱼成鱼HPG轴的反馈调节.  相似文献   

9.
10.
硒与氟离子对美丽猛水蚤的联合毒性   总被引:16,自引:3,他引:13  
为了探讨硒氟共存的毒性变化机制,按硒与氟离子1:10、1:20、和1:30三个浓度配比进行硒与氟对美丽猛水蚤的联合毒性实验,结果表明,硒与氟对美丽猛水蚤的单一毒性:96h Se^4+LC50为9.2(7.4-15)mg/L,96h F^-LC50为290(284-296)mg/L;硒与氟的联合毒性为拮抗作用,美丽猛水蚤是毒物联合毒性研究的优秀实验生物,毒性单位法及相加指数法都是测定水中毒物联合毒性  相似文献   

11.
The test was designed to assess the toxicity of methyl tert-butyl ether (MTBE) to Chlorella ellipsoidea and Aphanizomenon flos-aquae during 15 d with concentrations of MTBE from high (2.00×104 mg/L) to low (2 mg/L). The results showed that the toxicity was low when the concentration of MTBE was 1.00×104-2.00×104 mg/L (the greatest inhibition of growth-rate was 70%-71%, occurring on day 1-5). Low concentrations (2-500 mg/L) stimulated algal growth up to the greatest effect of 85%-200% when the concentration of MTBE was 50-100 mg/L on day 3-5. The low concentrations may lead to an algal bloom owing to overabundance, which represents an aquatic ecological risk. However, the stimulatory effect occurred only during the day 1-5 and disappeared gradually during the day 13-15. The toxicity of MTBE (72-120 h EC50) is 6.65×103-9.58×103 mg/L for C. ellipsoidea and that is 1.14×104-2.00×104 mg/L for A. spiroides. We found that the toxicity and ecological risk of MTBE for the algal community structure were low. The toxicity was influenced by the duration of the test. We suggest that the duration of the test should not be shorter than half a life-cycle.  相似文献   

12.
水稻幼苗对纳米氧化铜的吸收及根系形态生理特征响应   总被引:1,自引:0,他引:1  
以纳米氧化铜nano-CuO(10, 100mg/L)为研究对象,以微米氧化铜micron-CuO(10, 100mg/L)及铜离子Cu2+(1.4, 2.3mg/L)为对照,通过水培实验,探讨水稻对nano-CuO的吸收积累及其根系形态和生理特征响应.结果表明,各浓度(10, 100mg/L)nano-CuO处理条件下,水稻根部及地上部铜含量(根351~1444mg/kg dw;地上部9~45mg/kg dw)总体高于micron-CuO处理(根248~817mg/kg dw;地上部1.57~1.60mg/kg dw)及Cu2+处理(根147~220mg/kg dw;地上部14~26mg/kg dw),且在水稻幼苗根及茎透射电镜图片中均观察到nano-CuO的存在,指示水稻可通过纳米颗粒的形式吸收、转运nano-CuO. Nano-CuO在水稻根细胞中主要存在于核内体中,指示内吞作用是其进入根细胞的主要方式. Nano-CuO对水稻幼苗根系有较强的毒性作用,对各根系形态指标的抑制率为28%~74%,其中总根长、根体积和比表面积为最敏感;nano-CuO的吸收累积及纳米效应是其水稻根系毒性的主要原因.低浓度nano-CuO (10mg/L)胁迫时,水稻幼苗根系活力显著提高,总吸收面积和活跃吸收面积无显著差异;高浓度nano-CuO (100mg/L)胁迫时,水稻幼苗根系活力和总吸收面积显著降低.  相似文献   

13.
14.
物化-生化技术处理含氟废水的工程实践   总被引:1,自引:0,他引:1  
黄文玲 《环境科技》2008,21(6):34-36
江苏某农药生产企业产生大量含氟的高浓度生产废水,废水量为120t/d,进水ρ(CODCr)为10000mg/L,ρ(F^-)为500mg/L,采用物化-生化组合工艺进行处理。通过对农药废水处理的关键技术问题进行了讨论,对工程设计参数和污染物去除机理进行了探索,并进行了技术经济分析。实践证明,物化-生化组合工艺可以经济有效地实现农药废水的达标处理,出水ρ(CODCr)〈500mg/L,ρ(F^-)〈10mg/L,可以稳定达到开发区污水厂接管标准。  相似文献   

15.
Coal gasification effluent is a typical refractory industrial wastewater with a very poor anaerobic biodegradability due to its toxicity.Methanol was introduced to improve anaerobic biodegradability of real coal gasification wastewater,and the effect of methanol addition on the performance was investigated in a mesophilic upflow anaerobic sludge bed reactor with a hydraulic retention time of 24 hr.Experimental results indicated that anaerobic treatment of coal gasification wastewater was feasible with the addition of methanol.The corresponding maximum COD and phenol removal rates were 71% and 75%,respectively,with methanol concentration of 500 mg COD/L for a total organic loading rate of 3.5 kg COD/(m3 ·day) and a phenol loading rate of 0.6 kg/(m3 ·day).The phenol removal rate was not improved with a higher methanol concentration of 1000 mg COD/L.Substrate utilization rate (SUR) tests indicated that the SURs of phenol were 106,132,and 83 mg phenol/(g VSS·day) at methanol concentrations of 250,500,and 1000 mg COD/L,respectively,and only 45 mg phenol/(g VSS·day) in the control reactor.The presence of methanol could reduce the toxicity of coal gasification wastewater and increase the biodegradation of phenolic compounds.  相似文献   

16.
十种有机磷农药对扁藻的毒性   总被引:32,自引:1,他引:32  
报告了十种有机磷农药对扁藻生长的半数抑制浓度EC50值,依其毒性大小分:辛硫磷为剧毒;甲基异柳磷、对硫磷、甲基对硫磷为高毒;敌敌畏、氯化乐果、甲胺磷(江苏)、果保灵、甲胺磷(山东)为中等毒性;久效磷、杀灭毙为低毒,并初步探讨了有机磷农药结构和对微藻毒性大小的关系。  相似文献   

17.
The GC-Ion Trap MS is recently one of the most efficient instrumental analysis recommended for understanding the chemistry of volatile organic compounds, not only in water but even in the food chain and other environmental media (air and soil). Results of the experiment conducted on water samples from Kuguri and Yatsutani sampling stations showed considerably higher levels of organic enrichment (COD = 10 mg/L and 11 mg/L respectively). Total concentrations of Pb (0.072 mg/L and 0.093 mg/L) and Cd (0.004 mg/L and 0.011 mg/L) on the other hand, invariably exceeded the maximum allowable concentrations for human health and the living environment (Pb = 0.005 mg/L; Cd = 0.001 mg/L respectively). And the toxicity levels for these contaminants at LC50 showed critical impact on rainbow trout (hypersensitive species) at 0.14 mg/L for Pb and 0.007 mg/L for Cd in 96 hours respectively. Although these major contaminants including phenol and 3-, 4-cresol, showed relatively higher toxicity impact in the experimental media, it would remain contentious to justify any associated potential dangers without regular routine water monitoring, at least for a period of one year. Nevertheless, the data could serve as a benchmark through which other phenomena can easily be investigated.  相似文献   

18.
电子束辐照降解水体中磺胺间甲氧嘧啶   总被引:1,自引:0,他引:1  
应用电子束辐照初步探索了去除水体中磺胺间甲氧嘧啶(SMM)10mg/L的过程.研究了吸收剂量、自由基清除剂、无机盐等对辐照降解的影响.通过实验数据和模拟计算,推测了降解机理和降解路径,并对降解产物进行了毒性评估.结果表明,当吸收剂量为3.0kGy时,去除率高于99%,辐照降解效率高.在辐照降解过程中,还原消除占主导作用.降解反应遵循一级动力学方程.碳酸根、硫酸根和硝酸根等无机阴离子在一定的程度上会抑制SMM的降解.根据超高效液相色谱-质谱(UHPLC-MS)对降解产物的分析,结合高斯理论模拟,推断出9种可能的降解产物和相应的降解途径.费氏弧菌的毒性测试显示,辐照降解中间体毒性先升高后降低,在吸收剂量为2.0kGy达到最高值.  相似文献   

19.
IntroductionSignificantwaterqualitymanagementformitigationofenvironmentalpollutioncausedbyhazardouschemicalsisstillamatterofstringentenvironmentalconsiderationinJapan .Subsequently,regularon goingmonitoringareimplemented ,especiallyforsyntheticchemicals…  相似文献   

20.
以吲哚为燃料的微生物燃料电池降解和产电特性   总被引:4,自引:1,他引:3       下载免费PDF全文
以铁氰化钾为电子受体,在两极阴阳室内使用碳毛刷纤维为电极材料构建了循环式微生物燃料电池(MFC),研究了以吲哚为单一燃料和吲哚+葡萄糖为混合燃料条件下MFC的产电特性以及对吲哚和COD的去除效果.结果表明,以1000mg/L葡萄糖+250mg/L吲哚为混合燃料时,MFC的最高电压和最大功率密度分别为660mV和51.2W/m3(阳极),MFC运行10h对吲哚和COD的去除率分别为100%和89.5%;分别以250,500mg/L吲哚为单一燃料时,MFC的平均最高电压分别为115,118mV,最大功率密度分别为2.1,2.3W/m3(阳极).在MFC中,250,500mg/L吲哚被完全降解的时间分别为6,30h.MFC能够利用吲哚为燃料,在实现高效降解吲哚的同时对外产生电能,可用于处理含有毒且难降解有机物的焦化工业废水.  相似文献   

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