国内外饮用水水质标准中微生物指标的比较综述

本文系统介绍了我国现行的生活饮用水水质标准(GB 5749-2006),并与国外的水质标准(美国EPA《国家饮用水水质标准》、WHO《饮用水水质准则》、欧盟《饮用水水质指令》及其他国家的饮用水标准)中微生物指标进行综述比较,分析了各水质标准中微生物指标及其限量,并对我国饮用水水质标准的实施和发展提出建议。本文认为,与国外水质检测标准相比,虽然我国饮用水水质微生物指标新增致病性大肠埃希氏菌、病原性原生动物贾第鞭毛虫和隐孢子虫,基本与世界水质检测指标接轨,但仍缺少病毒和产毒藻类等影响水质安全、威胁水环境安全和生物健康的微生物项目。考虑到日益严重的食品安全现状,饮用水水质指标的及时更新和采样环节的标准化,检测报告的公正公开已成为保证饮用水水质安全的重要手段。     

优化EPA 1623法检测生活饮用水中隐孢子虫和 贾第鞭毛虫

目的建立提高生活饮用水中隐孢子虫和贾第鞭毛虫(两虫)检出率的方法。方法用1.2μm微孔滤膜通过真空抽滤的方式过滤两虫加标样品,后将滤膜置于磷酸缓冲盐溶液(phosphate buffer saline,PBS)中进行超声洗脱,收集洗脱液离心富集卵囊和孢囊;按照GB/T 5750.12-2006《生活饮用水卫生标准检验方法》洗脱液离心富集卵囊和孢囊。将2种试验方法离心收集到的卵囊和孢囊分别进行免疫磁分离和荧光抗体染色,计算2种方法的回收率。结果优化方法对隐孢子虫和贾第鞭毛虫的加标回收率分别为60%和56%,标准方法GB/T 5750.12-2006的加标回收率分别为22%和20%。结论优化方法对于提高生活饮用水中两虫检出率是有效的,且可以达到降低检测成本的目的。     

拒绝病原体 饮用健康水

<正> 饮用水的安全性日益受到人们的关注,它是多种肠道传染病的病原体传播载体。作为饮用水主要水源的地表水源污染是当前迫切需要解决的问题。在众多污染物中原生动物的污染危害性尤为严重。隐孢子虫和贾第鞭毛虫两类原生动物对水源的污染和对人类的危害已被证实,它们是人畜共患的流行性寄生虫病,具有     

饮用水中贾第鞭毛虫和隐孢子虫能力验证的研究

通过对贾第鞭毛虫和隐孢子虫能力进行验证,分析水中两虫回收率的影响因素。采用Enivrochek~(TM)法对能力验证样品进行测定。本试验方法的回收率满足组织方的要求,可应用于水样的检测。     

提高饮用水“两虫”检测回收率的方法探讨——Filta-Max xpress快速法

本文对免疫磁分离荧光抗体法测定水中隐孢子虫和贾第鞭毛虫过程中3个关键步骤——浓缩、分离和染色过程的加标回收率情况分别进行比对试验,对如何提高饮用水中"两虫"检测回收率提出合理化建议。     

隐孢子虫和贾第鞭毛虫的危害及检测

病原微生物对水体的污染以及子饮用水中的存在是一个重要的公共卫生问题。微小的隐孢子虫和贾地鞭毛虫(简称两虫)被认为是世界上最主要的导致人体腹泻的水源性原动物寄生虫。本文对两虫的危害、检测进行了阐述,并对武汉市的9个自来水厂的源水和出厂水进行了检测,结果显示源水和出厂水中均未检出两虫。     

圆孢子虫病—一种新发现的食源性疾病（综述）

圆孢子虫病(Ｃｙｃｌｏｓｐｏｒｉａｓｉｓ)是由圆孢子虫(Ｃｙｃｌｏｓｐｏｒａｃａｙｅｔａｎｅｎｓｉｓ)引起的人体寄生虫病,1977年首次发现并于1979年首先由Ａｓｈｆｏｒｄ报道。[1]近几年美国等国家陆续发生多起食源性圆孢子虫病暴发事件,使得圆孢子虫成为继隐孢子虫、等孢球虫后的又一种重要的人体寄生球虫。我国虽未出现大规模食源性暴发,但迄今已报道了16例圆孢子虫感染的病例。[2]本文就圆孢子虫及其感染的基本情况综述如下。1　形态与生活史圆孢子虫是一种由单细胞构成的寄生虫,曾被称为藻青菌样体、球虫样体或大隐孢子虫等,1993年…     

食品安全监测车开赴抗震救灾前线

应国家质检总局的要求,在相关技术专家的护送下,中国检验检疫科学研究院研制的食品、饮用水安全移动检测装置——食品安全监测车日前开赴四川抗震救灾第一线,支援灾区人民的自救和重建家园行动,为保障灾区食品、饮用水和公共卫生安全发挥作用。     

分型方法在单核细胞增多性李斯特菌监测溯源中的应用研究进展

单增李斯特菌(LM)是引起人和动物李斯特菌病的重要食源性病原菌,具有较高的病死率,严重危害人类公共卫生安全和畜牧业发展。快速准确的鉴定LM污染来源,对有效控制李斯特菌病的暴发和蔓延发挥重要作用。建立高效快捷的分型方法是LM溯源的关键。目前LM分型方法主要分为表型分型和分子分型方法,每种分型方法各有优劣,具有适用不同的流行病学调查范围。本文就LM分型方法的研究进展进行综述,以期为开展LM的暴发确认和溯源检测方法的选择提供参考依据,对防御并控制LM引起的食源性疾病的暴发和传播具有重要意义。     

饮用水生物性污染物快速检测技术研究进展

饮用水微生物安全问题大多源于细菌、病毒、原生动物和藻类等生物性污染。加强饮用水生物性污染物的检测与监测, 防止消费者饮用存在生物性污染的水, 对保障饮用水的生物性安全具有十分重要的意义。当前饮用水微生物检测工作中, 主要采用国标检测方法对4项常规微生物及2项非常规微生物指标进行检测, 存在指标覆盖不全、耗时较长、操作复杂等不足, 难以满足饮用水生物性污染物监测的现实需求。因此, 本文重点对饮用水生物性污染物的各种快速检测与筛查技术, 如微生物快速测试片检测技术、生物荧光检测技术、流式细胞仪检测技术、PCR检测技术、等温扩增检测技术、基因芯片检测技术、高通量测序检测技术等进行综述、比较与探讨, 以期为饮用水中生物性污染物快速检测与筛查提供适宜的技术参考基础。     

Giardia, Cryptosporidium, and Cyclospora and their impact on foods: a review.

While the risk from pathogenic microorganisms in foods has been recognized for hundreds of years, bacterial agents are generally implicated as the contaminants. Although many outbreaks of gastroenteritis caused by protozoan pathogens have occurred, it is only in the last 3 years that attention has focused on protozoan association with foodborne transmission. Recognized as waterborne parasites, Giardia, Cryptosporidium, and Cyclospora have now been associated with several foodborne outbreaks. The oocysts and cysts of these organisms can persist and survive for long periods of time both in water and on foods. While Cyclospora oocysts require a maturation period, Cryptosporidium oocysts and Giardia cysts are immediately infectious upon excretion from the previous host. As a result, these parasites have emerged as public health risks and have become a concern to the food industry. More than 200 cases of foodborne giardiasis (seven outbreaks) were reported from 1979 to 1990. Four foodborne Cryptosporidium outbreaks (with a total of 252 cases) have been documented since 1993. Cyclospora caused a series of sporadic outbreaks of cyclosporasis throughout North America that have affected over 3,038 people since 1995. Control and prevention of protozoan foodborne disease depends upon our ability to prevent, remove, or kill protozoan contaminants. This review will address the biology, foodborne and waterborne transmission, survival, and methods for detection and control of Giardia, Cryptosporidium, and Cyclospora.     

Epidemiology, microbiology, and risk assessment of waterborne pathogens including Cryptosporidium

Cryptosporidium is one of a suite of relatively recently emerging pathogens of concern in drinking water. Based on human dose-response tests, guidelines for exposure yielding defined levels of endemic risk have been developed. This risk assessment procedure is grounded in the process used for chemical risk assessment. From outbreak data, critical concentrations in water that may lead to epidemic levels have been postulated. Development of these levels will be discussed. Validation of the information using outbreak reports from the 1993 Milwaukee incident can be made. Use of this approach must be tempered by the existence of substantial waterborne cases in the absence of detectable oocyst levels as in the Las Vegas outbreak, and (apparent) high levels of oocysts without (apparent) significant health effects as in the case of the (at the time of this writing) ongoing incident in Sydney, Australia.     

Foodborne illness associated with Cryptosporidium and Giardia from livestock

Waterborne outbreaks caused by Cryptosporidium and Giardia are well documented, while the public health implications for foodborne illness from these parasites have not been adequately considered. Cryptosporidium and Giardia are common in domestic livestock, where young animals can have a high prevalence of infection, shedding large numbers of oocysts and cysts. Molecular epidemiological studies have advanced our knowledge on the distribution of Cryptosporidium and Giardia species and genotypes in specific livestock. This has enabled better source tracking of contaminated foods. Livestock generate large volumes of fecal waste, which can contaminate the environment with (oo)cysts. Evidence suggests that livestock, particularly cattle, play a significant role in food contamination, leading to outbreaks of cryptosporidiosis. However, foodborne giardiasis seems to originate primarily from anthroponotic sources. Foodborne cryptosporidiosis and giardiasis are underreported because of the limited knowledge of the zoonotic potential and public health implications. Methods more sensitive and cheaper are needed to detect the often-low numbers of (oo)cysts in contaminated food and water. As the environmental burden of Cryptosporidium oocysts and Giardia cysts from livestock waste increases with the projected increase in animal agriculture, public health is further compromised. Contamination of food by livestock feces containing Cryptosporidium oocysts and Giardia cysts could occur via routes that span the entire food production continuum. Intervention strategies aimed at preventing food contamination with Cryptosporidium and Giardia will require an integrated approach based on knowledge of the potential points of entry for these parasites into the food chain. This review examines the potential for foodborne illness from Cryptosporidium and Giardia from livestock sources and discusses possible mechanisms for prevention and control.     

Cryptosporidium and Giardia in commercial and non-commercial oysters (Crassostrea gigas) and water from the Oosterschelde, The Netherlands

The intestinal parasites Cryptosporidium and Giardia cause gastro-enteritis in humans and can be transmitted via contaminated water. Oysters are filter feeders that have been demonstrated to accumulate pathogens such as Salmonella, Vibrio, norovirus and Cryptosporidium from contaminated water and cause foodborne infections. Oysters are economically important shellfish that are generally consumed raw. Commercial and non-commercial oysters (Crassostrea gigas) and oyster culture water from the Oosterschelde, The Netherlands, were examined for the presence of Cryptosporidium oocysts and Giardia cysts. Nine of 133 (6.7%) oysters from two non-commercial harvesting sites contained Cryptosporidium, Giardia or both. Six of 46 (13.0%) commercial oysters harboured Cryptosporidium or Giardia in their intestines. Data on the viability of (oo)cysts recovered from Oosterschelde oysters were not obtained, however viable (oo)cysts were detected in surface waters that enter the Oosterschelde oyster harvesting areas. The detection of Cryptosporidium and Giardia in oysters destined for human consumption has implications for public health only when human pathogenic (oo)cysts that have preserved infectivity during their stay in a marine environment are present. Our data suggest that consumption of raw oysters from the Oosterschelde may occasionally lead to cases of gastro-intestinal illness.     

Cryptosporidium contamination in harvesting areas of bivalve molluscs

Cryptosporidium contamination was evaluated in areas in Galicia (northwestern Spain) where bivalve molluscs are harvested. Galicia is the main mussel-producing region in Europe. Data were collected on water contamination of effluents that are discharged into these areas. Cryptosporidium spp. were detected by immunofluorescence microscopy and molecular methods in 71% of the river water samples (n = 7), 64% of raw sewage samples (n = 11), 50% of effluents from wastewater treatment plants (n = 16), and 29.3% of the mussel samples (Mytilus galloprovincialis, n = 184). Cryptosporidium parvum was identified in all samples of contaminated mussels, Cryptosporidium muris was found in three samples of effluent from wastewater treatment plants, and Cryptosporidium baileyi was found in a sample of raw sewage. Further studies are needed to determine the parasitological quality of water in these shellfish harvesting and recreational areas. Cryptosporidium could be a public health risk from consumption of raw or undercooked contaminated molluscs and use of contaminated waters for recreational purposes.     

Comparison of Rapid Methods for Detection of Giardia spp. and Cryptosporidium spp. (Oo)cysts Using Transportable Instrumentation in a Field Deployment

Reliable, sensitive, quantitative, and mobile rapid screening methods for pathogenic organisms are not yet readily available, but would provide a great benefit to humanitarian intervention units in disaster situations. We compared three different methods (immunofluorescent microscopy, IFM; flow cytometry, FCM; polymerase chain reaction, PCR) for the rapid and quantitative detection of Giardia lamblia and Cryptosporidium parvum (oo)cysts in a field campaign. For this we deployed our mobile instrumentation and sampled canal water and vegetables during a 2 week field study in Thailand. For purification and concentrations of (oo)cysts, we used filtration and immunomagnetic separation. We were able to detect considerably high oo(cysts) concentrations (ranges: 15-855 and 0-240 oo(cysts)/liter for Giardia and Cryptosporidium, respectively) in 85 to 300 min, with FCM being fastest, followed by PCR, and IFM being slowest due to the long analysis time per sample. FCM and IFM performed consistently well, whereas PCR reactions often failed. The recovery, established by FCM, was around 30% for Giardia and 13% for Cryptosporidium (oo)cysts. It was possible to track (oo)cysts from the wastewater further downstream to irrigation waters and confirm contamination of salads and water vegetables. We believe that rapid detection, in particular FCM-based methods, can substantially help in disaster management and outbreak prevention.     

微萃取技术在水中土霉味化合物检测的应用

土霉味是国内外饮用水处理中最常见的问题之一,它通常与微生物活动有关。虽然土霉味化合物的浓度非常低(ng/L),但仍然达到了人类的感知阈值。因此为了检测这些低浓度的土霉味化合物就必须采用高灵敏度、高选择性的方法进行富集处理。本文综述了吸附微萃取、液相微萃取等微萃取技术在水中土霉味化合物检测的研究进展,为提高水中土霉味化合物检测提供借鉴。微萃取效率主要受萃取纤维的种类、萃取模式、添加无机盐的浓度、萃取温度和萃取时间等因素的影响。微萃取是最近发展起来的一种新型样品前处理技术,该方法操作简单、成本低、富集效率高、所需有机溶剂用量极少,是一种环境友好的萃取新技术,可与气相色谱、液相色谱等仪器联用。     

基于适配体检测农药残留的技术进展

随着多种农药地广泛使用,农药残留带来的健康问题越来越受到大众的关注。基于核酸适配体进行农药残留的检测技术在有毒有害物质检测方面发挥着重要作用。相比于抗体,适配体具有稳定性好、容易合成和修饰、靶标范围广等优势。近些年来,发表了一些适配体与荧光检测、电化学检测、拉曼光谱等方法进行结合的新型方法。这些方法可以更加准确、灵敏地检测出农药残留量。其中有部分新方法实现了高通量检测。本文总结了近5年使用的核酸适配体进行农药残留检测的方法,同时比较了前几年的检测方法。     

Comparative risk analysis of six volatile organic compounds in California drinking water

The widespread use and storage of volatile organic compounds (VOCs) in the United States has led to releases of these chemicals into the environment, including groundwater sources of drinking water. Many of these VOCs are commonly found in public drinking water supplies across the nation and are considered by state or federal agencies to be potentially carcinogenic to humans. In this paper, we evaluate the detection frequencies, detected concentrations, and relative cancer risks of six VOCs in drinking water sources in California from 1995 to 2001. We find that during this 7-year period, the most frequently detected VOCs in sampled drinking water sources were chloroform (12-14%), PCE (11-13%), and TCE (10-12%). Detection frequencies in water were lower for 1,1-DCE (3-6%), MTBE (1-3%), and benzene (<1%). Mean detected concentrations were also consistently above California's primary maximum contaminant level for some VOCs, including benzene, PCE, and TCE. Although none of the six VOCs necessarily poses a significant public health threat from drinking water exposures, 1,1-DCE and benzene werefound to pose the greatest cancer risk relative to the other VOCs. However, after adjusting for the occurrence of each VOC in drinking water, chloroform and PCE were found to pose the greatest relative cancer risk. Despite media reports about significant MTBE contamination of drinking watersupplies in California, MTBE detections were infrequent and this chemical was found to pose the least cancer risk relative to the other VOCs.     

酰胺类除草剂的残留检测技术研究进展

酰胺类除草剂是一类高效、高选择性的除草剂。该类除草剂具有杀草谱广、价格低廉、施用方便等优点,而广泛应用于近代农业生产。但其易在环境中发生迁移和富集,并可通过食物链传递最终进入人体,其残留问题对人类健康和生态环境的威胁已经引起广泛关注。目前,酰胺类除草剂残留的检测研究中主要涉及大豆、玉米、土壤和水等多种基质。由于样品基质的复杂程度不同,其样品前处理技术多种多样。相应的仪器检测技术也逐渐从单组分残留测定向多组分残留同时检测方向发展。本文对酰胺类除草剂的毒性危害、限量标准、样品前处理技术和残留检测方法进行了综述,并对其今后的发展方向进行了展望,以期为开展酰胺类除草剂的残留检测提供参考。