傍河取水工程对黄河水微囊藻毒素的去除效果

目的探讨傍河取水工程对黄河水中微囊藻毒素、藻细胞的去除效果,为该工程的推广应用和政府决策提供科学依据。方法现场水样采集后,低温保存运回实验室。细胞计数板法测定藻细胞密度,ELISA法测定微囊藻毒素。结果傍河取水工程对藻细胞和微囊藻毒素的去除率均在90.0%以上。结论傍河取水工程对藻细胞和微囊藻毒素有很好的去除效果。     

水源水微囊藻毒素及其控制方法研究

饮用水源藻毒素污染已越来越引起人们的关注。微囊藻毒素（Microcystins，MCYST）是由蓝藻的部分藻属产生的环肽化合物，性质稳定，已被证明具有明显的肝毒性，是肝肿瘤促进剂之一。常规水处理工艺对MCYST的作用效果不理想，多项研究表明臭氧、光化学氧化、氯系氧化物、活性炭以及生物控制等方法能较好地去除毒素。     

饮用水中微囊藻毒素去除效果研究

目的 探讨高效、经济、可行的去除饮用水中藻毒素的水处理方法.方法 采用烧杯试验,研究不同水处理工艺[混凝沉淀(液态聚合氯化铝、固态聚合氯化铝、聚合硫酸铁、聚丙烯酰胺),氧化(高锰酸钾、二氧化氯、臭氧),吸附(粉末活性炭)]对微囊藻毒素的去除效果,并进行工艺优化组合和验证;藻毒素的检测采用酶联免疫法(ELISA).结果 混凝沉淀可少量去除水中微囊藻毒素(去除率为4.3%～29.7%),臭氧等氧化剂预处理工艺与混凝沉淀工艺组合后,对微囊藻毒素的去除率提高,达83.3%～91.9%;成本效益分析表明,所选臭氧预处理工艺及"氧化剂 吸附剂"预处理工艺使每吨水处理成本仅增加0.03～0.14元.结论 在常规水处理基础上进行臭氧、高锰酸钾氧化、二氧化氯、粉末活性炭等预处理,能较好地去除微囊藻毒素,且经济可行.     

黄河滩地傍河取水工程对黄河水微囊藻毒素的去除效果

目的探讨黄河滩地傍河取水工程对黄河水中微囊藻毒素的去除效果。方法 2008年夏秋季节(5月6日至11月5日),对黄河和傍河取水工程"九·五"滩地5眼管井进行了6个月的水样采集,每季8次,共16次,ELISA法测定水样中微囊藻毒素含量。结果黄河水中微囊藻毒素含量均在国家《生活饮用水卫生标准》微囊藻毒素-LR基准值以下,且秋季微囊藻毒素含量平均值高于夏季(P<0.01),滩地5眼管井中微囊藻毒素含量均低于黄河水,傍河取水工程对微囊藻毒素的去除效果与距黄河干道距离无关。结论傍河取水工程对微囊藻毒素有着很好的去除效果。     

微囊藻毒素污染及其促肝癌作用研究进展

淡水水体的富营养化导致了蓝藻水华的普遍发生,微囊藻毒素是由蓝藻的部分藻属产生的环肽化合物,具有毒性大、分布广、结构稳定等特性,从而成为水环境中的重要潜在危害物质。微囊藻毒素已被证明具有明显的肝毒性,是肝肿瘤的促进剂之一。本文就微囊藻毒素的污染现状、肝毒性作用及其促肝癌机制等方面的研究进展进行了综述。     

节球藻毒素在小鼠体内分布的研究

目的 研究和探讨节球藻毒素在动物体内分布的靶器官及其在靶器官中的细胞水平定位。方法 用核素^125Ⅰ标记节球藻毒素,将^125Ⅰ节球藻毒素标记物注入小鼠体内,分别经核素示踪和放射性自显影技术研究协^125Ⅰ节球藻毒素在小鼠体内整体水平和细胞水平的分布。结果 核素示踪显示,静脉注射、腹腔注射和口服3种不同途径进入体内的^125Ⅰ节球藻毒素,主要分布在肾脏,其次为肝脏。放射性自显影研究表明,^125Ⅰ节球藻毒素在肾脏和肝脏内分别定位于肾皮质的肾细胞核内和肝细胞核内。结论 肾脏和肝脏是节球藻毒素的2个靶器官。     

水处理剂投加量对水中微囊藻毒素去除效果影响

目的:研究水处理剂投加量对去除水中微囊藻毒素的影响,探讨最佳投加剂量.方法:采用烧杯试验,研究不同工艺、不同投加量对微囊藻毒素的去除效果;采用酶联免疫法检测藻毒素.结果:混凝沉淀工艺对微囊藻毒素去除率最低为4.3%,最高为29.7%;氧化处理工艺对微囊藻毒素去除率最低为13.0%,最高为92.0%,随着氧化剂投加剂量的增加,微囊藻毒素的去除率大幅度提高,臭氧、二氧化氯、高锰酸钾的最高去除率分别为92.0%、87.0%、78.3%,91.7%的水样经处理后微囊藻毒素浓度达到GB5749规定;粉末活性炭吸附工艺对微囊藻毒素去除率最低为4.0%,最高为40.0%,随着投加量增加,藻毒素去除率提高.水处理剂的最佳投加量分别为:聚合氯化铝(液体)3.0 mg/L,聚合氯化铝(固体)1.0 mg/L,聚合硫酸铁10.0 mg/L,聚丙烯酰胺0.1 mg/L,高锰酸钾1.0 mg/L,二氧化氯6.0 mg/L,臭氧5.6 mg/L,粉末活性炭4.0 mg/L.结论:单纯增加混凝(絮凝)剂的投加量不能提高藻毒素的去除效果,增加臭氧(O3)、二氧化氯(ClO2)、高锰酸钾(KMnO4)等氧化剂和粉末活性炭等吸附剂的投加量,可提高对藻毒素的去除效果.     

藻类肝毒素毒理学研究进展

藻类肝毒素主要由污染水体的蓝绿藻产生,其主要靶器官为肝脏。整体和离体动物实验均表明,藻类肝毒素的作用机机制可能与蛋白磷酸酶－１和蛋白磷酸酶－２Ａ的抑制有关。本文对藻类肝毒素在分子结构,急慢性毒性以及毒作用机制等方面的研究进展加以综述。     

微囊藻毒素遗传毒性研究进展

微囊藻毒素是淡水水体污染物中对人体健康威胁最大的一种细胞内毒素,主要表现为肝毒性[1],长期接触可损害细胞遗传物质。目前主要用微核试验、Ames试验、彗星试验等体内外试验检测其遗传毒性。作者综述了微囊藻毒素遗传毒性研究的试验方法、检测终点,并对其可能机制进行了初步的探讨。     

饮用水藻毒素对健康的影响与污染控制研究进展

近年来 ,随着水体富营养化程度的加剧 ,导致藻类大量繁殖。其中某些藻类会产生藻毒素 ,一定程度上污染了水体 ,此类毒素具有水溶性 ,我国目前常用的水处理工艺难以将其彻底去除 ,使人民的身体健康受到威胁。本文就国内外目前饮用水藻毒素对人体健康影响和控制与处理方法作一综述。1　藻毒素污染及其健康影响淡水中的某些藻类会产生藻毒素 ,其中大部分毒素具有水溶性 ,直接污染了水体。世界各地均有人类因饮用被藻毒素污染的水或间接食用被藻毒素污染的淡水中的生物而出现肝损害、胃肠炎、腹泻和皮炎等疾病的报道。流行病学调查也显示饮水中…     

鱼腥藻毒素与微囊藻毒素的免疫毒性研究

目的蓝藻水华暴发日益频繁,蓝细菌滋生、产生大量有毒代谢产物——藻毒素。最典型的有鱼腥藻毒素-A(Anatoxin-a,AnTX-a)和微囊藻毒素(Microcystins,MC)。AnTX-a是一种快速致死性神经毒素,MC是普遍存在的细胞和肝毒素,被这些毒素污染的水体和食物会给人畜健康带来严重危害,也可能对人群公共健康造成威胁。方法通过查阅国内外研究进展,概述了AnTX-a和MC对机体免疫系统的毒性作用。结果近年来大量研究表明,AnTX-a和MC对机体的危害不仅仅限于神经系统和实质器官,还能对人类、动物以及水生生物中免疫细胞和免疫分子产生毒性效应。结论此综述从免疫学角度,为深入探讨AnTX-a和MC对机体的联合免疫毒性作用和机理提供新的视野和思路。     

Detection of potentially producing cylindrospermopsin and microcystin strains in mixed populations of cyanobacteria by simultaneous amplification of cylindrospermopsin and microcystin gene regions

Cyanobacterial blooms are frequently formed by heterogeneous populations of toxin-producing and non-producing strains. Microcystins (MC) and cylindrospermopsin (CYN) are the most representative cyanobacterial toxins. We have developed a multiplex PCR assay that allows simultaneous detection of MC(+) and/or CYN(+) strains in mixed populations of cyanobacteria. Various primer sets were designed using mcy and aoa gene sequences related with MC and CYN synthesis respectively, to amplify at the same time aoa and mcy sequences. Purified DNA, cultured cell mixtures and field samples with MC and CYN producing strains were used as DNA template. The results show: (i) the expected amplicons were only observed with toxic strains; (ii) cells were suitable as a source of purified DNA for the multiplex PCR; (iii) the assay could detect simultaneously 3 aoa and 3 mcy gene regions with mixed CYN(+) and MC(+) cyanobacteria cells. The method could be applied to environmental samples, allowing in a rapid, economical and easy way to detect simultaneously the presence of CYN(+) and MC(+) cyanobacteria in sestonic fractions of water samples.     

Field Studies on the Environmental Factors in Controlling Microcystin Production in the Subtropical Shallow Lakes of the Yangtze River

Microcystin (MC) problem made more and more care about in China, intercellular MC (Int-MC) and cellular MC (Cel-MC) were important contents to reflect the producing-MC ability by cyanobacteria and by lakes. To study the correlations between Int-MC, Cel-MC concentration and biological and environmental factors, eight cyanobacterial blooming lakes were studied in the middle and lower reaches of the Yangtze River. Microcystin-RR (MC-RR) and Microcystin-LR (MC-LR) were the primary toxin variants in our data. From the linear correlations between MC and environmental factors, cellular-YR had significant correlation with most of chemical factors except total nitrogen (TN) and the ratio of total nitrogen and total phosphorus (TN/TP), most intracellular MC analogues had significant correlations with total dissolved nitrogen (TDN), ammonium (NH (4) (+) ), nitrite (NO (2) (-) ), TP, total dissolved phosphorus (TDP), Microcystis. From the canonal correspondence analysis, Int-MC concentrations were closely related with the chemical and biological factors, such as TP, total organic carbon (TOC), chlorophyll a (Chl a), Microcystis biomass, et al. While Cel-MC contents, especially Cel-RR and Cel-LR, were closely related with light environmental in the lakes such as water depth and transparence.     

Cyanobacterial toxins: removal during drinking water treatment, and human risk assessment

Cyanobacteria (blue-green algae) produce toxins that may present a hazard for drinking water safety. These toxins (microcystins, nodularins, saxitoxins, anatoxin-a, anatoxin-a(s), cylindrospermopsin) are structurally diverse and their effects range from liver damage, including liver cancer, to neurotoxicity. The occurrence of cyanobacteria and their toxins in water bodies used for the production of drinking water poses a technical challenge for water utility managers. With respect to their removal in water treatment procedures, of the more than 60 microcystin congeners, microcystin-LR (L, L-leucine; R, L-arginine) is the best studied cyanobacterial toxin, whereas information for the other toxins is largely lacking. In response to the growing concern about nonlethal acute and chronic effects of microcystins, the World Health Organization has recently set a new provisional guideline value for microcystin-LR of 1.0 microg/L drinking water. This will lead to further efforts by water suppliers to develop effective treatment procedures to remove these toxins. Of the water treatment procedures discussed in this review, chlorination, possibly micro-/ultrafiltration, but especially ozonation are the most effective in destroying cyanobacteria and in removing microcystins. However, these treatments may not be sufficient during bloom situations or when a high organic load is present, and toxin levels should therefore be monitored during the water treatment process. In order to perform an adequate human risk assessment of microcystin exposure via drinking water, the issue of water treatment byproducts will have to be addressed in the future.     

Influence of a Toxic <Emphasis Type="Italic">Microcystis aeruginosa</Emphasis> Strain on Glutathione Synthesis and Glutathione-S-Transferase Activity in Common Carp <Emphasis Type="Italic">Cyprinus carpio</Emphasis> (Teleostei: Cyprinidae)

We evaluated the effects of aqueous extracts of the cyanobacterium-producing microcystin (MC), Microcystis aeruginosa (strain RST9501), on detoxification capacity and glutathione (GSH) synthesis in liver, brain, gill, and muscle—as well as apoptotic protease (calpain) activity in liver and brain—in the common carp Cyprinus carpio (Teleostei: Cyprinidae). Experimental groups were defined as follows: (1) control (CTR); (2) carp treated with an aqueous extract from the toxic cyanobacteria M. aeruginosa in a final MC concentration of 25 μg/kg (MC 25); and (3) carp treated with an aqueous extract from the toxic cyanobacteria M. aeruginosa in a final MC concentration of 50 μg/kg (MC 50). Carp were gavaged with a cyanobacterial aqueous solution or MilliQ water (CTR group). The experiment was conducted for period of 48 h comprising two gavages with a 24-h interval between them. Some of the parameters analyzed in liver, brain, gill, and muscle included activity of the enzymes glutathione-S-transferase (GST), glutamate cysteine ligase (GCL), glutathione reductase (GR), and GSH concentration. We also evaluated GST pi concentration by Western blot as well as calpain activity in liver and brain samples. In carp liver from the MC 50 group, we observed a decrease in GST and GCL activity, which was accompanied by a decreased GSH concentration. In addition, liver calpain activity was highly induced in carp at both MC doses. Thus, MC ingestion affected the liver antioxidant status through decreasing the GSH concentration and the activity of the enzyme involved in its synthesis (GCL). It also decreased the MC detoxification capacity of the liver because total GST activity decreased, a result that cannot be ascribed to GST pi levels. Because GSH acts as an uncompetitive inhibitor of calpain, its decrease should explain the higher activity of this apoptotic enzyme. The main goal of this study was to show that a decrease in GSH concentration is related to decreased activity of GCL, the limiting enzyme involved in GSH synthesis. Because MCs are phosphatase inhibitors and GCL is allosterically inhibited by phosphorylation, the cellular hyperphosphorylation state induced by MC exposure could act as a modulator factor for antioxidant defenses.     

微囊藻毒素无害化处理的研究进展

富营养化湖泊中的微囊藻毒素对环境和人类健康的危害已成为全球关注的重大环境问题之一。而常用的水处理工艺难以将其彻底去除,开发用于处理微囊藻毒素的新技术越来越迫切。本文就微囊藻毒素无害化处理的研究进展作综述。     

Removal of micro-organisms by filtration through unwoven cloth coated with a pyridinium-type polymer.

Unwoven cloth coated with 32 mg/g of a copolymer of N-benzyl-4-vinyl-pyridinium chloride and styrene was found to be effective in removing micro-organisms from water. In experiments demonstrating removal of Escherichia coli by filtration through ten sheets of the unwoven cloth, the rate of removal was 99.99% at a filtration rate of 2.6 cm/h, and remained at 99% even at a high filtration rate of 300 cm/h and a low influent concentration of the bacterial cells such as 10(3) cells/ml. The rate of removal tended to increase with a decrease in the influent bacterial concentration. Seven other bacteria and two yeasts were effectively removed by filtration through the unwoven cloth. Filtration through the unwoven cloth was also effective in removing spores of fungi from water but was not very effective in removing bacteriophage T4 from aqueous solution.     

上海市供水系统微囊藻毒素LR含量调查

目的　调查上海市供水系统中微囊藻毒素LR(MC- LR)的污染状况及常规水处理工艺对MC- LR的去除效果。方法　运用高效液相色谱法 (HPLC)检测有代表性的水源、水厂及出厂水样中MC LR的含量。结果　源水中MC- LR浓度随采样点及采样季节变化 ,在夏末秋初易形成污染高峰 ,最高达 2 . 38μg L。混凝沉淀、加氯消毒对去除毒素有一定的效果 ,而过滤则效果不明显 ,在出厂水中也能检测到MC- LR ,最高达1. 2 7μg L。结论　夏秋季节上海市供水系统源水受到以MC- LR为代表的蓝藻毒素的污染 ,郊区源水污染较重 ,常规水处理工艺不能有效地去除水中的微囊藻毒素。     

Microcystin Removal by a Naturally-Occurring Substance: Pumice

Microcystins (MCs) are among the most prevalent and potent of the cyanobacterial toxins (cyanotoxins) and their potential occurrence in waters required for drinking has prompted investigations into remedial water treatments for their removal. We have investigated the suitability of local pumice, as a possible low-cost material for environmental application for the removal of cyanotoxins. Adsorption and desorption rates of pure MC-LR, one of the most common and toxic forms of MC and with crude extracts of the cyanobacterium. Microcystis aeruginosa containing MCs, were studied using bench-scale, pumice-packed glass columns, with good retention of the toxins being achieved. Research is in progress to optimize MC removal and to determine the applicability of pumice as a treatment material for cyanotoxin removal.     

蓝藻提取物对原代培养大鼠肝细胞的毒性作用研究

用蓝藻提取物处理大鼠肝细胞,通过测定乳酸脱氢酶渗出率、显微镜直接观察细胞形态改变及吖啶橙／溴乙啶联合染色后观察细胞核的改变来评价其毒性作用及方式。结果：乳酸脱氢酶渗出率呈明显的剂量和时间效应式增加;细胞形态改变包括收缩、变圆、变小、出现胞膜包;细胞核的改变有碎裂、浓缩、染色质收缩等,发生这类改变的细胞占总细胞数的比例随剂量和时间的增加而增加。结论：蓝藻提取物对原代培养大鼠肝细胞有明显的毒作用,其主要作用方式是引起凋亡