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1.
《环保科技》2014,(4):41-41
急性毒性污染物随食物进入人体在短时间内造成机体损害,出现临床症状,造成急性中毒。引起急性中毒的污染物有细菌及其毒素、霉菌及其毒素和化学毒物。慢性毒性食物被某些有害物质污染,其含量虽少,但由于长期持续不断地摄入体内并且在体内蓄积,在几年、  相似文献   

2.
谷巍  韩承辉 《环境科技》1997,10(4):32-34
应用主成分分析法对张家河水质监测数据进行分析,获得了技术该河流断面水质的6个主成分。通过对这6个主成分分析,将污染物进行分类,从中推出该河污染来源。  相似文献   

3.
海洋微藻产生的溶血毒素(Hemolytic toxins)对海洋生物影响极大,是造成鱼类和贝类死亡的重要原因之一。国内外对于溶血毒素的研究尚处在起步阶段,海洋微藻溶血毒素的成分非常复杂,对于毒素化学结构的分析是制约溶血毒素研究的关键因素。本文总结了已经报道的溶血毒素的化学结构,共分为五类,即糖脂类(Glycolipids)、大环内酯类(Macrolides)、长链多羟基多烯类(Long-chain polyenes)、聚醚类(Polyethers)以及卟啉类(Porphyrins)化合物,为深入研究溶血毒素性质提供依据。  相似文献   

4.
天然化合物中生物活性成分研究的发展促进了分子生物学、分子药理学等边缘学科的进展。为了寻找有实用意义的生物分子模型,在高生物活性与低分子量两方面进行选择,国外对河豚毒素(Tetrodotoxin,TTX)和石房蛤毒素(Saxitoxin,STX)等天然毒物做了大量研究工作。笔者曾著文综述了石房蛤  相似文献   

5.
建立了可用于微量腹泻性贝毒(diarrhetic shellfish poisoning,DSP)毒素分析的高效液相色谱-质谱联用(high performance liquid chromatography-mass spectrometry,LC-MS)分析方法,并于2009年4月从青岛近海团岛湾采集浮游植物样品,应用所建立的LC-MS方法对手工挑取的渐尖鳍藻(Dinophysis acuminata)细胞产毒状况进行了分析。结果显示,该方法具有良好的灵敏度和精密度,能够对30个鳍藻细胞中的毒素成分进行检测。运用该方法从渐尖鳍藻样品中检测到了大田软海绵酸(okadaic acid,OA)、鳍藻毒素1(dinophysistoxin 1,DTX1)和扇贝毒素2(pectenotoxin 2,PTX2)等毒素成分,细胞中OA,DTX1和PTX2毒素的含量分别为2.54 pg/cell,4.04 pg/cell和1.73 pg/cell,这是首次对我国近海鳍藻产毒状况的报道。  相似文献   

6.
本文综述了当前水体低浓度有机毒物去除的各种新技术。从化学原理着手,对这些技术的机理进行了分析,提出了新的分类方法,并在此基础上,设想了新的可能有应用前景的去除水体中低浓度有机毒物的方法。  相似文献   

7.
主成分分析法在环境评价中的应用   总被引:3,自引:0,他引:3  
主成分分析法是一种实用的统计分析方法.本文在阐述主成分分析法原理的同时,对秦皇岛市海滨浴场的水质状况做了综合评价.结果表明:主成分分析法处理环境数据客观性强,并能够反映评价区内主要污染特征.一、主成分分析法应用的一般原理和步骤1.主成分分析法应用的一般原理设有p个污染指标,对n个监测点来说,共有n×  相似文献   

8.
保护和改善环境,防止食品污染,是一项十分重要的工作。粮食是各类食品中最大的一宗,食用量大,影响面广,因此,防止粮油污染具有特殊的重要性。粮油主要污染来源有三:一是农药和贮粮药剂污染;二是工业“三废”污染;三是霉菌毒素污染。为便于叙述,分药剂、重金属、其它化学毒物和霉菌毒素污染四个部分作以介绍。  相似文献   

9.
为掌握流沙湾养殖区贝类毒素的特征情况,作者进行了贝类和浮游植物样品采集。小白鼠生物法和高效液相色谱法的检测结果表明:(1)PSP毒素在各季节均有出现,但含量值较低,且染毒的生物品种不多。春季样品中的毒素成分较多,有6种,属低毒性值和中等毒性值成分,但其总毒性值相对较高;而在冬季样品中,春季出现的各毒素成分均未被检出,取而代之的是两种新的中高毒性值的毒素成分,但其总毒性值低于春季。污染的主要贝类品种是牡蛎。(2)DSP毒素的含量值较高,季节性和染毒的生物品种均较为普遍。但OA成分未检出。(3)在贝类消费方面,PSP和DSP毒素一年四季均应予以关注,但PSP更应注意春季,而DSP应多注意秋季。在该海域,应重点注意的是DSP毒素的危害。(4)该海域存在能产生DSP毒素的具尾鳍藻Dinophysis caudata。  相似文献   

10.
主成分分析法用于环境质量评价的探讨   总被引:4,自引:0,他引:4  
文章将主成分分析法用于某河流水质评价,得出该河流历年水质变化趋势,但得到的水质评价等级却与实际情况不符。通过对主成分分析法原理进行研究,得出两个结论:主成分分析法可用于比较不同时间或不同地点的环境质量优劣;主成分分析法不能评价出环境质量等级。这主要是由主成分分析法的本质特点所决定。  相似文献   

11.
长江口赤潮多发区潜在有毒藻类和赤潮毒素的初步调查   总被引:1,自引:0,他引:1  
通过长江口赤潮多发区2003年-2005年的有毒藻类和贝类原产地赤潮毒素的监测,初步结果表明该海域存在多种潜在有毒藻类,主要包括产麻痹性贝毒(PSP)的链状亚历山大藻(Alexandrium catenella)、塔玛亚历山大藻(A.tamarens),产腹泻性贝毒(DSP)的渐尖鳍藻(Dinophysis acuminata,)、具尾鳍藻(D.caudata)、倒卵形鳍藻(D.fortii);产记忆缺失性贝毒(ASP)的尖刺拟菱形藻(Pseudo-Nitzschia pungens)、多列拟菱形藻(P.multiseries)、柔弱拟菱形藻(P.delicatissima )和多纹拟菱形藻(P.multistriata);产神经性贝毒(NSP)的短凯伦藻(Karenia brevis),其他有毒有害藻类包括红色裸甲藻(Gymnodinium sanguineum)、Heterocapsa circularisquama、米氏凯伦藻(K.mikimotoi)、Chatenela marina,Heterisigma akashiwo等其他有毒藻类。有毒藻类种类5、6月份较多,产腹泻性贝毒(DSP)和产记忆缺失性贝毒(ASP)的潜在有毒藻类常年均在该海域出现,这些有毒有害藻类多数密度并不高,Heterocapsa cirularisquama曾在2003年和2005年两次形成赤潮,并导致部分养殖贻贝死亡,米氏凯伦藻于2005年5-6月在长江口海域形成大规模赤潮,并导致养殖鱼类死亡。与有毒藻类监测同步开展了赤潮毒素检测,长江口贝类赤潮毒素检出时段主要集中在5-8月份,麻痹性贝毒和腹泻性贝毒的检出率分别为5%和15%左右,敏感种类为养殖的紫贻贝。  相似文献   

12.
对有毒化学品进行简介 ;建议从生理毒性、属性毒性及生命周期等方面建立有毒化学品的污染评价系统 ,为有毒化学品的应用、管理和处理处置提供理论依据 ;针对不同的有毒化学品及其排放情况与浓度组分拟选用物化处理法、化学处理法及生物处理法作为污染控制技术。  相似文献   

13.
N,N-二甲基甲酰胺(DMF)废水处理研究进展   总被引:16,自引:0,他引:16  
DMF是一种性能优良的有机溶剂和精细化工产品中间体,工业用途广泛,但DMF有毒性,难生物降解.在此综述了DMF废水的主要处理方法,包括生物降解、吸附、萃取、化学氧化、碱性水解等,分析了各种方法的优缺点及适用范围,并展望了DMF废水处理工业化应用的研究方向.  相似文献   

14.
宋伦  吴景  李楠  杜静  王昆  刘桂英  王鹏 《中国环境科学》2018,38(8):3049-3059
以18S rDNA V4区作为目标基因,利用自行设计的真核浮游植物鉴定引物V4(F/R),结合高通量测序技术,对辽东湾2014年四季海水中真核藻类多样性进行了检测.结果发现了辽东湾毒害藻类共29种,曾引发赤潮或褐潮的种类有19种,可导致鱼类大规模死亡的有8种,主要为甲藻门.有18种疑似为辽东湾新记录种,其中9种在中国海域未见报道;发现麻痹性贝毒(PSP)产毒藻8种,腹泻性贝毒(DSP)产毒藻2种,产虾夷扇贝毒素(YTX)产毒藻3种,神经性贝毒(NSP)产毒藻2种,溶血毒素(hemolysin)产毒藻13种,另外还有1种褐潮产毒藻(EPS).辽东湾检出的毒害藻类中有8种自养型、1种异养型、20种混合营养型藻类.麻痹性贝毒、虾夷扇贝毒素、溶血毒素在夏季风险较高,神经性贝毒在秋季风险较高,腹泻性贝毒在春、夏季风险均较高,辽东湾东西两岸是贝毒风险高发区.辽东湾春季水温对YTX、NSP产毒藻影响显著负相关;夏季COD、Oil、DIN、Pb、Cd对各产毒藻类影响显著正相关;秋季各环境因子对各产毒藻类影响不显著;冬季Zn、As、Oil、DIN对各产毒藻类影响显著正相关,水温对各产毒藻类影响显著负相关,各产毒藻类与环境因子关联性有待于进一步研究.  相似文献   

15.
水环境中微囊藻毒素研究进展   总被引:60,自引:2,他引:58  
随着水体污染和富营养化进程的加剧,淡水水华暴发的频率和强度亦趋严重,笔者综述了有毒水华发生过程中释放的主要次级代谢物——微囊藻毒素的研究现状。该毒素是一类具有多种异构体的环状多肽物质。由于其毒性大、分布广、结构稳定,从而成为水环境中的潜在危害物质。对微囊藻毒素的产生、迁移及转化途径的研究已成为关注热点。微囊藻毒素作为安全性评价的风险因子,其分析方法主要有液相色谱和酶联免疫法等。为改善水源水质,逐步发展了包括物理、化学、生物等手段的控制方法。在总结国内外研究的基础上,根据我国实情,提出了微囊藻毒素在大型富营养化湖泊治理中的研究内容和方向。   相似文献   

16.
为解决贝类产品检测实验室严重缺乏贝类毒素标准样品的现状,保证小鼠生物法及酶联免疫法等腹泻性贝类毒素检测结果的准确,可靠和可比,本研究制备出腹泻性贝类毒素标准样品。将腹泻性贝类毒素阳性的新鲜贝类去壳后取中肠腺,匀浆,冷冻干燥等步骤制备冻干粉,均匀性和稳定性检验结果表明该样品均匀,稳定,满足标准样品的要求,以多家实验室定值的方式对标准样品进行定值,定值结果采用标准值±扩展不确定度的方式表示:即(8.83±0.60)×10-6(k=2)。该标准样品可用于腹泻性贝类毒素检测过程的方法验证与质量控制。  相似文献   

17.
The 1989 Massachusetts Toxics Use Reduction Act (TURA) instituted a preventive approach to chemical pollution and wastes: reducing toxic chemicals at the source through prevention planning, public reporting of chemical input, and fees for chemical use. The act also created the Massachusetts Office of Technical Assistance for Toxics Use Reduction (OTA), a voluntary program, to make onsite visits to companies that request assistance. OTA staff review the use of toxic chemicals at the facility, and make recommendations for either using substitutes, or using the chemicals more efficiently. Because TURA requires covered companies (large quantity toxics users) to report chemical input (what they use), output (resulting chemical waste), and a production index, it is possible to measure trends in toxics use relative to production, and waste byproduct per pound of chemical use input. These are uniquely precise measurements of a company's ability to accomplish the form of pollution prevention known as toxics use reduction.From 1993 to 2002, companies used approximately 500 million pounds (227 million kg) less toxic chemicals than they were expected to use, based on past performance. Those companies that received onsite technical assistance visits from OTA made substantially greater improvements in TUR performance than those not visited, and as compared to their own performance after being visited. They reduced an average of 9.4% more toxics use after being visited than before, and the difference was statistically significant. More companies in the visited group made progress than companies not visited, and had greater reductions than those not visited by nearly all measures.The results of two additional studies supported these findings of program effectiveness. One study examined companies that dropped out of the system, and found that those that were visited employed toxics use reduction to achieve below-threshold use amounts more frequently than those that were not visited. The other study, an independent research project using econometric methods to determine the causative relevance of provided assistance, found OTA's service to be an explanatory factor associated with significant toxics use and byproduct reductions.  相似文献   

18.
采用等毒性单位比的方法研究了对氯硝基苯(para-nitrochlorobenzene,P-NCB)、间二硝基苯(m-dinitrobenzene,M-DNB)、2,4-二硝基苯氯苯(chloro-2,4-dinitrobenzene,CDNB)对锦鲤鱼(Brocarded carp)的单一毒性和二元、三元混合体系联合毒性。用四种方法(毒性单位法(TU)、相加指数法(AI)、混合毒性指数法(MT)I和相似性参数法(λ))对联合毒性类型进行了评价。结果表明,3种硝基苯对锦鲤鱼的单一毒性大小顺序为:CDNB>M-DNB>P-NCB。P-NCB与M-DNB的联合毒性48小时之前为拮抗作用,48小时后为协同作用,P-NCB与CDNB的联合毒性类型为拮抗作用,而M-DNB与CDNB以及三元混合体系的联合毒性机制均为协同效应。  相似文献   

19.
This paper employs state-of-the-art time series analysis to examine the long-run economic and institutional drivers of toxic chemical use behavior in the U.S. Toxic chemicals are classified into growth, Environmental Kuznets Curve (EKC), and kinked-growth chemicals, according to their long-run use trend behavior. Cointegration analysis shows that while some toxic chemicals have been successfully reduced by regulatory efforts, a majority of the toxic chemicals used in commercial products share a long-run equilibrium with national accounts and industrial production, suggesting that toxic chemical use has been largely driven by changes in GDP, industrial production, and private R&D investments, rather than by government regulations. Estimated structural break results indicate that the 1986 Emergency Planning and Community Right-to-Know Act, which created the Toxic Release Inventory has had impact on the consumptive use of more poisonous industrial chemicals than command-and-control regulations.  相似文献   

20.
The excessive accumulation of potentially toxic metals (Pb and Cd) in coastal wetlands is among the main factors threatening wetland ecosystems. However, the effects of water table depth (WTD) on the risk and binding mechanisms of potentially toxic metals in sediments remain unclear. Here, sediments from different WTD obtained from a typical coastal wetland were evaluated using a newly developed strategy based on chemical extraction methods coupled with high-resolution spectroscopy. Our findings indicated that the WTD of the coastal wetland fluctuates frequently and the average enrichment factor for Pb was categorized as minor, whereas Cd enrichment was categorized as moderate. High-resolution spectroscopy techniques also demonstrated that organic functional groups and partly inorganic compounds (e.g., Fe-O/Si-O) played a vital role in the binding of Pb and Cd to surface sediments. Additionally, mineral components rather than organic groups were mainly bound to these metals in the bottom sediments. Collectively, our findings provide key insights into the potential health effects and binding characteristics of potentially toxic metals in sediments, as well as their dynamic behavior under varying sediment depths at a microscale.  相似文献   

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