延安市污水处理厂各工段重金属元素的含量分析

采取延安市污水处理厂各工段污水,利用电感耦合等离子体发射光谱法(ICP-AES),对其中Zn、Cu、Pb、Mn和Cr 5种重金属元素的总量进行测定,结果表明部分活性污泥回流到厌氧池后,几种重金属元素在厌氧池和氧化沟中的去除率都较高。     

Phytotoxicity of municipal sewage sludge composts related to physico-chemical properties, PAHs and heavy metals

The aim of the study was to determine the influence of the composting on the phytotoxicity of sewage sludge in relation to their physical-chemical properties, heavy metals and polycyclic aromatic hydrocarbons content. Four municipal sewage sludges were composted for 76 days. A Phytotoxkit Test and pot experiment with Lepidium sativum were used for bioassay. The total PAH content in sludges ranged from 3674.1 to 11236.3 microg kg(-1). Heavy metals content was in the range Cd (1.9-76 mg kg(-1)), Cr (27.6-120 mg kg(-1)), Cu (156-335 mg kg(-1)), Pb (37.5-59.5 mg kg(-1)), Ni (21.7-155 mg kg(-1)) and Zn (1015-1385 mg kg(-1)). The results showed a varied toxicity of sewage sludge in relation to the plant tested. In the case of two sludges a 100% inhibition of seed germination were noted. Sludge composting limited their negative influence on most of the phytotoxicity parameters. Only chlorophyll concentration was often lower than in the plant bred on compost obtained from sludge.     

Assessment of the environmental hazard from municipal and industrial wastewater treatment sludge by employing chemical and biological methods

Chemical analyses and toxicity testing were employed in conjunction to evaluate the environmental hazard from the wasted sludge generated during the biological treatment of urban and industrial wastewaters. Chemical analyses included determination of seven polychlorinated biphenyls (PCBs), 13 polycyclic aromatic hydrocarbons (PAHs), total organic carbon (TOC), and seven heavy metals (As, Cd, Cr, Cu, Pb, Mn, and Zn) in sludge and sludge leachates deriving from two standard leaching procedures: (a) the mild leaching test EN-12457-2 proposed by EC and (b) the relatively aggressive toxicity characteristic leaching procedure (TCLP) leaching test proposed by US EPA. Acute toxicity measurements were performed in aqueous sludge elutriates and leachates by using bioluminescence bacteria. The urban sludge was found to be more enriched with PAHs than the industrial sludge, however, at levels below the EU limits for sludge application. The total PCB content (Sigma7PCBs) in both sludges, particularly in the industrial sludge, exceeded the proposed European limit for sludge use as soil amendment. With regards to their heavy metal content, both sludges met the requirements for use in agriculture. The urban sludge exhibited high ecotoxicity, while the industrial sludge with almost two times lower toxicity was classified as not toxic to slightly toxic. The EN and the TCLP leaching procedures resulted in different sludge characterizations both from chemical and from ecotoxicological points of view. The EN procedure appeared to be more sensitive to the potential environmental risk from sludge disposal. The results of the study revealed the necessity for combining chemical with ecotoxicological criteria for integrated characterization of wasted sludge and the need for harmonization of the methods employed for waste classification.     

Removal and destruction of intestinal parasitic protozoans by sewage treatment processes

This paper reviews the literature which addresses the occurrence of intestinal protozoan parasites in sewage as well as the removal and destruction of these pathogens in sewage treatment processes. The concentration of intestinal protozoa within sewage depends upon the catchment; the prevalence and intensity of human infection within the catchment; the contribution of animal waste to the sewage and the prevalence and intensity of animal infection within the catchment. Some research indicates that some sewage treatment processes may result in relatively high removal efficiencies of some intestinal protozoa, whereas other data indicate that the concentration of cysts and oocysts discharged in sewage effluent may be in the order of several thousand per litre. For some protozoan parasites, such as Cyclospora, Microsporidia and Isospora, knowledge is scarce on the potential importance of sewage in their transmission and their likely removal and destruction by sewage treatment processes.     

Cytogenotoxicity of sewage sludge leachate before and after calcium oxide-based solidification in human lymphocytes

Present study aimed to establish the chemical composition of sewage sludge leachate before/after calcium oxide-based solidification using energy dispersive X-ray fluorescence (EDXRF). The other aim was to determine leachate effects on human lymphocyte and DNA integrity in vitro using a battery of bioassays (DNA diffusion assay, micronucleus test and comet assay) to determine effects of those complex mixtures of elements on cell and DNA integrity. EDXRF showed that nickel concentration in the leachate of untreated sludge was 18.5 times higher than the upper permissible limit for inert waste landfills. Other elements were kept below the permissible values. After sludge solidification, leachate concentrations of Cr, Mn, Fe, Ni, Cu, Zn, and Pb dropped 1.6, 2.7, 37, 5.9, 3.2, 7.8, and 2.6 times, respectively. Untreated sludge leachate was cytogenotoxic to lymphocytes, and may lead to adverse effects on the exposed human populations, but calcium oxide-based solidification reduced these effects in significant manner.     

Assessing risk of heavy metals from consuming food grown on sewage irrigated soils and food chain transfer

Heavy metal pollution of soils resulting from sewage and wastewater irrigation is causing major concern due to the potential risk involved. In the present study Musi River and its environs were assessed for heavy metal contamination. The study area was assessed for Zn, Cr, Cu, Ni, Co and Pb in soils, forage grass, milk from cattle, leafy and non-leafy vegetables. Partitioning pattern of soil revealed high levels of Zn, Cr, and Cu associated with labile fractions, making them more mobile and plant available. The associated risk was assessed using hazard quotient (HQ). Human risk was assessed in people known to consume these contaminated foods by analyzing metals concentrations in venous blood and urine. Results showed high amounts of Pb, Zn, Cr, and Ni compared to permissible limits. HQ was found to be high for Zn followed by Cr and Pb with special reference to leafy vegetables particularly spinach and amaranthus.     

Application of toxicity identification evaluation procedures on wastewaters and sludge from a municipal sewage treatment works with industrial inputs

A comparison of influent and effluent wastewater toxicities to Daphnia magna was undertaken to determine the most representative aqueous fraction for future toxicity identification evaluation (TIE) studies. Wastewater samples originated from a wastewater treatment plant which receives mainly domestic wastewater and industrial effluents. The TIE results reveal that the key toxicant contained in the influent was 2-propylbezaldehyde oxime. Results suggest that greater attention needs to be given to the receiving influent containing 2-propylbezaldehyde oxime to avoid damaging the bacterial populations in the primary activated sludge process. In addition, in order to evaluate the applicability of the reuse of activated sludge as a fertilizer in agriculture, TIE studies were also performed on water extracts from surplus sludge.     

绍兴市污水处理厂污泥处理系统的改进和优化

绍兴市污水处理厂的污泥处理系统以进口设备为主,操作难度较大。通过对运行模式加以优化,并进行了一系列技术改造,有效地提高了污泥处理效率。     

中毒事件处置移动操作平台的设计与探讨

目的：研究设计中毒事件现场处置装备的移动操作平台。方法：以机电一体化、集成化为主导,对中毒现场处置内容中涉及的装备开展集成平台设计研究。结果：中毒现场处置过程中的流行病学调查、实验室检测及个体防护等装备以现场应急箱方式进行箱囊化装备,移动操作平台可以现场快速进行毒物鉴定和现场信息及时传输。结论：中毒事件处置移动操作平台对现场处置装备的集成化满足了现场应急处置需求。     

医院污水中SARS冠状病毒核酸的检验

目的　了解收治SARS病人的定点医院污水中是否含有病毒和病毒核酸。方法　采用载阳电荷滤材吸附浓集污水中的SARS冠状病毒 ,消毒前浓集污水 2 5L ,消毒后 2 5～ 5 0L ;采用VERO细胞培养及RT -PCR技术检测SARS冠状病毒。结果　建立的阳电荷浓集方法对污水中加标f2 噬菌体回收率平均 12 7% ,而SARS冠状病毒回收率只有 1 0 2 %。消毒前在 30 9医院和小汤山医院污水的6d监测中均检测出SARS冠状病毒核酸 ;消毒后 ,在 30 9医院只有 3d监测出病毒核酸 ,其余样品均未检出病毒核酸 ;两医院所有的污水回收液中均未检出活病毒或具有感染性的病毒。结论收治SARS病人医院污水中含有SARS冠状病毒核酸 ,但没有检出活病毒或具有感染性的病毒 ,因此 ,在当时条件下 ,医院污水 ,尤其是消毒后污水传播SARS冠状病毒可能性较小。     

The use and disposal of household pesticides

Most pesticides are synthetic chemicals manufactured specifically for their toxic properties to the target species, and widely used globally. Several epidemiological studies in the United States have suggested health concerns arising from the chronic exposure of young children to pesticides in the domestic environment. In the UK very little is currently known about how nonoccupational pesticides are being used or disposed of. Any use of pesticides is a potential risk factor for children's exposure, and any potential exposure is likely to be reduced by the parents' adopting precautionary behaviour when using these pesticide products. This was investigated using a sample of 147 parents from the Avon Longitudinal Study of Parents and Children cohort in and around Bristol, through an in-depth interview between August and November 2001. The results of this study add to the understanding of the underlying behaviour of parents applying pesticide products in the home environment in the UK. Pesticides are readily available, and are normally purchased in do-it-yourself shops and supermarkets and mostly disposed of in domestic waste. Safety was stated by 45% of parents to be the most important factor to consider when buying a pesticide. When buying pesticide products, labels were stated to be the most important source of information about pesticides. However, a third of parents stated they would not follow the product label exactly when using a product, just under half felt labels were both inadequate and hard to understand, and about 10% of parents would not take notice of warnings on the pesticide label. Less than half of parents would use gloves when applying a pesticide, although the use of protective equipment such as gloves during the application of pesticides could greatly reduce the exposure. It is a public health concern that the instructions on the labels of products may not always be understood or followed, and further understanding of user behaviour is needed.     

"阳雪"轮突发公共卫生事件的成功处置

[目的]为口岸突发公共卫生事件的有效处置积累宝贵经验。[方法]总结对巴拿马籍“阳雪”轮上发生1名中国船员突然死亡,另1名船员同样症状并已送往菲律宾医院进行抢救,船舶还载有20名密切接触患者的船员的突发公共卫生事件的处置经验。[结果]紧急启动预案,精心做好各种应急准备工作；加强组织领导,成立疫情处置领导小组和4个工作小组；果断处置,及时沟通,消除了口岸突发公共卫生事件的危害。[结论]应急预案要周密,疫情报告要迅速,防控措施要果断,沟通协调要及时。     

Estimating the burden of illness in an Ontario community with untreated drinking water and sewage disposal problems

The Hamilton-Wentworth regional health department was asked by one of its municipalities to determine whether the present water supply and sewage disposal methods used in a community without piped water and regional sewage disposal posed a threat to the health of its residents. Three approaches were used: assessments by public health inspectors of all households; bacteriological and chemical analyses of water samples; and completion of a specially designed questionnaire by residents in the target community and a control community. 89% of the 227 residences in the target community were found to have a drinking water supply that, according to the Ministry of Environment guidelines, was unsafe and/or unsatisfactory. According to on-site inspections, 32% of households had sewage disposal problems. Responses to the questionnaire revealed that the target community residents reported more symptoms associated with enteric infections due to the water supply. Two of these symptoms, diarrhea and stomach cramps, had a relative risk of 2.2 when compared to the control community (p less than 0.05). The study was successfully used by the municipality to argue for provincial funding of piped water.     

污水处理厂排水中的环境雌激素研究进展

对污水处理厂排水中环境雌激素的概念、来源以及目前的研究重点进行了简要介绍,综述了近年来污水处理厂排水中环境雌激素的分离和鉴定以及对水生生物繁殖影响的研究结果,并探讨了生物标志物——卵黄蛋白原(Vtg)在环境雌激素中的应用,指出了污水处理厂排水中环境雌激素的研究方向。     

实验室污水处理工艺及效果分析

目的对中国疾病预防控制中心BSL-2实验室污水进行生物灭活后排至污水处理站,通用实验室污水直接排至污水处理站,由污水处理站集中进行处理,将出水水质处理至国家规定排放标准,保证环境安全。方法污水处理站用次氯酸钠和聚合氯化铝为消毒剂,采用"混凝-沉淀-过滤-活性炭吸附-消毒"的处理工艺进行处理。结果每季度由环保局对出水水质进行检测。处理后的水质符合GB 18466-2005《医疗机构水污染物排放标准》。结论 BSL-2实验室采用高温高压灭活,污水处理站集中二次处理的工艺流程;通用实验室采用污水处理站集中处理的工艺流程是安全可靠、合理可行的。