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.

室内空气主要污染物及其健康效应

室内空气质量与人体健康紧密相关。室内空气污染物的种类众多、来源广泛 ,对人体健康造成的危害十分复杂 ,可累及呼吸、免疫和血液等多个系统。目前 ,室内空气中存在的污染物以燃料燃烧产物、建筑装饰材料产生的挥发性有机化合物和生物性污染物等为主。

图书馆环境污染及其防治

图书馆内污染物按性质分为化学性污染物、物理性污染物、生物性污染物和放射性污染物。本文按此分类对图书馆内主要污染物的来源、危害和防治进行分析。

你了解水体污染吗?

水体污染的定义水体污染是指未经处理的工业废水、生活污水、农业回流水和其他废弃物,直接或间接排入江河湖海,超过水体的自净能力,造成地表水和地下水水质恶化,从而降低水体使用价值和使用功能的现象。水体污染物的种类排入水体的污染物按其性质主要分为物理性、化学性和生物性污染物3类。许多情况下积累污染物是综合发挥作用的。

论食品安全风险分析在食品质量管理中应用

近些年,随着人们生活水平的提高,对食品安全有更高的要求。因为食品安全关乎到人们的身体健康。在食品质量管理中,为了确保食品安全,需要分析食品安全风险,采取有效措施预防安全风险,不断提升食品安全系数。随着食品安全事故的增加,我国政府对食品安全问题更加重视。要解决食品安全问题,就需要加强食品质量管理,根据形成风险的原因进行评估。食品安全风险涉及的环节比较多,主要包括养殖、生产、加工、流动、

Treatment of Benzene,Toluene and Xylene Contaminated Air in a Bioactive Foam Emulsion Reactor

A novel bioactive foam emulsion bioreactor for benzene,toluene and xylene(BTX)contaminated air streams treatment has been developed.The gas-liquid interfacial area by biocompatible foam and driving force for mass transfer by a water immiscible organic phase were increased in this reactor.The effect of several parameters such as gas residence time,oxygen content,and organic phase concentration on bioreactor performance was studied. Experimental results showed an average elimination capacity(EC)of 220 g·m3·h -1with removal efficiency(RE) of 89.59%for BTX inlet concentration of 1 g·m3at 15 s gas residence time in the bioreactor.The statistical developed model predicted that the maximum elimination capacity of the reactor for BTX could be reached to 423.45 g·m3·h -1.Continues operation of the bioreactor with high EC and RE was demonstrated by optimizing the operational parameters of the bioreactor.Overall the results suggest that the bioreactor developed can be very effective systems to treat BTX vapors.

Bioremediation potential of spirulina:toxicity and biosorption studies of lead

This study examines the possibility of using live spirulina to biologically remove aqueous lead of low concentration (below 50 mg/L) from wastewater. The spirulina cells were first immersed for seven days in five wastewater samples containing lead of different concentrations, and the growth rate was determined by light at wavelength of 560 nm. The 72 h-EC50 (72 h medium effective concentration) was estimated to be 11.46 mg/L (lead). Afterwards, the lead adsorption by live spirulina cells was conducted. It was observed that at the initial stage (0–12 min) the adsorption rate was so rapid that 74% of the metal was bio- logically adsorbed. The maximum biosorption capacity of live spirulina was estimated to be 0.62 mg lead per 105 alga cells.

Effect of Salinity on Reeds in the Treatment of High Salinity LandfilI-Leachates Using HFs

The growth of reeds was impeded remarkably under a salinity of 15.0±3.4 g CI·L-1 in the first year of this experiment, recovered in the second year and then increased year-by-year afterward. The growth of reeds under a salinity of 9.3±1.9 g CI·Ll was much better than those under 15.0 ± 3.4 g CI·L1. The stress effect was significant for shoot extension but not for the quantity of shoots increase. The dense vegetation bed during the vegetation period （June-October） provided a high rate of evapotranspiration and water loss from HFs （horizontal subsurface flow constructed wetlands）, which made large contributions to reducing pollutant load. The HFs with die-back reeds in the non-vegetation periods （November-March） provided slight evapotranspiration and water loss and made less of a contribution to reducing pollutants removal compared to HFs with the dense vegetation bed in the vegetation periods. However, the HFs with die-back reeds in the non-vegetation periods had higher removal performance than the HF without reeds. This indicated that the rhizosphere of HFs with reeds might play important roles, such as that the microbes around rhizomes might have a higher amount of pollutant-removing microbe activity than those in the HF without reeds during the non-vegetation period.

Effects of Nutrients on Biofouling Formation and Preponderant Bacteria Diversity in Recirculating Cooling Water System

A series of orthogonal array experiments were conducted using carbon source, ammonia nitrogen and total phosphorus （TP） as major influencing factors to investigate the effects of nutrients on biofouling formation and preponderant bacteria diversity in the recirculatiug cooling water system. Carbon source was demonstrated to be the most significant determinant affecting the biofouling formation. A minimum biofouling outcome was obtained when BOD2, NHa＋-N and TP were 25, 10, and 1 mg/L, respectively. Then the preponderant bacteria strains in biofouling mass under two typical culture conditions （negative and favorable） were identified applying both traditional biochemical methods and further molecular biology technology with phylogenetic affiliation analysis, which indicated that Enterobacteriaceae Enterobacter, Micrococcaceae Staphylococcus, Bacillaceae Bacillus, Enterobacteriaceae Proteus, Neisseriaceae Neisseria and Pseudomonadaceae Pseudomonas were dominant under negative condition, while Enterobacteriaceae Klebsiella, Enterobacteriaceae Enterobacter and Microbacterium - under favorable one.

Use of antioxidant enzymes of clam Ruditapesphilippinarum as biomarker to polycyclic aromatic hydrocarbon pollution

The typical organic pollutant polycyclic aromatic hydrocarbon(PAH) anthracene was selected as a contaminant to investigate its eff ects on the activities of superoxide dismutase(SOD), catalase(CAT) and glutathione peroxidase(GSH-Px) in the clam Ruditapes philippinarum. The results show that SOD, CAT and GSH-Px had diff erent induction and inhibition reactions to anthracene stress, and that three diff erent organs in R. philippinarum(visceral mass, muscle tissue and mantle) had diff erent sensitivities to anthracene stress. This study suggest that SOD activities of the visceral mass, CAT activitities of the mantle and the visceral mass, and GSH-Px activity of the muscle tissue could be used as sensitive indicators of anthracene stress in R. philippinarum.

Eggshell as a Source of Novel Bioactive Molecules

This review will focus on the more abundant eggshell specific matrix proteins localized in the chicken eggshell （cuticle layer eggshell matrix and shell membranes） that are involved in eggshell mineralization and protecting the egg against microbial contamination, including ovocalyxin-36, ovocleidin-17, ovocalyxin-32 and ovocalyxin-25. Further understanding of these proteins and their mechanisms in egg defence could lead to the development of novel neutraceuticals for human health, additives to animal feed for healthy flocks, or enhanced eggs for human consumption.

Pilot study on combined process of catalytic ozonation and biological activated carbon for organic pollutants removal

A combined process of catalytic ozonation in the presence of a novel heterogeneous catalyst and biological activated carbon was investigated for the removal of priority control organic pollutants, the reduction of genotoxicity, and the improvement of biodegradable dissolved organic carbon (BDOC). Results confirm that the catalytic ozonation has higher effectiveness for the removal of refractory harmful organic pollutants, the reduction of genotoxicity and the increase of bio-degradability of organics than ozonation alone, which results in lower pollution load for subsequent biological activated carbon process, and then leads to less organic pollutants penetrating biological activated carbon. The novel catalytic ozonation with this combined process exhibits excellent performance to guarantee the safety of drinking water.

Characteristics of Heavy Metal Circulation in Biosphere

In order to control heavy metal pollution effectively, this paper reviews heavy metal source and transport characteristics in heavy metal circulation in bio- sphere, including geochemical cycle and biological cycle of heavy metals. The inter- body of geochemical cycle of heavy metals includes soil, gas as well as water body, and the interbody of biological cycle of heavy metals includes environment, plant, microorganisms and animals. As to macro-cycle, transportation character in each interbody is different. Heavy metal circulation in different interbody interacts with each other and is in dynamic balance. Heavy metals in soil include two parts, i.e. active and inert forms, which are in dynamic equilibrium. This equilibrium may be affected by different physicochemical factors. Heavy metal content at different soil depth reflects historical accumulation level of heavy metal. In contrast to agri- cultural eco-system itself, industrial and urban activities are of great menace. Fluvial transport and atmospheric input are significant pathways of heavy metal circulation. Sludge plays an accumulative role of heavy metals, and can release its heavy met- als to water body causing secondary pollution. Balance of heavy metal immobiliza- tion and release is interrupted by physicochemical characters and microbial activity. Temperature can influence atmospheric heavy metal content, and volatile heavy meal precipitation is an indLspensable source in soil and water body. In regard to micro-cycle, plants is the main part in heavy metal cycle, microorganisms play roles in accelerator and animals in recipient. Specific transportation and assigned location of heavy metal in plants are adopted to keep internal heavy metal equilibrium.

防治土壤污染 须先摸清家底

日前,国务院印发《土壤污染防治行动计划》,对今后一个时期我国土壤污染防治工作做出全面战略部署。这是继'治气''治水'之后,我国又打响'治土'攻坚战,彰显了党和政府治理环境突出问题的决心。但目前我国土壤污染存在底数不清。

Using a Two-Liquid-Phase System to Investigate the Biodegradation of Trichlorobenzenes

Due to easy volatilization of volatile organic compounds from water,it is difficult to monitor their aerobic biodegradation in the traditional single water system.Whether a two-liquid-phase system(TLPS) could overcome this obstacle and enhance the degradation of volatile contaminants? In this study,a TLPS composed of silicone oil and water was employed to investigate the biodegradation of volatile compounds,trichlorobenzenes(TCBs),by the adapted microorganisms in an activated soil.The degradation and volatilization of TCBs in TLPS and in a single water system were compared.The results showed that due to volatilization losses of TCBs,the mass balance of TCBs in a single water system was very low.In contrast,using TLPS could effectively inhibit the volatilization losses of TCBs and achieved a very good mass balance during the biodegradation process.Meanwhile,the TLPS could increase microbial activity and microbial growth during the degradation process.With TLPS,the TCB degradation was in descending order of 1,2,4-TCB> 1,2,3-TCB>> 1,3,5-TCB,which was related to the exposed concentration of the contaminants in soil.This study showed that TLPS could be employed as an effective tool to evaluate the biodegradation of volatile hydrophobic organic compounds,which could not be achieved with the traditional single water system.