居家须防有害化学品污染

很多产品都可能使人暴露于有毒化学物质中,有的有毒物质甚至可以在人体内积聚。以下将列举普通家居用品存在的一些潜在问题,并推荐能较少接触有毒化学物质的方法;     

特殊有毒物质的销毁技术

本文简要回顾了特殊有毒物质—化学武器的高温焚烧销毁技术及其存在的缺点。对销毁化学武器的几种替代技术做了评价 ,较详细地介绍了最新的等离子弧销毁技术。这些技术原则上也适用于有毒有害废弃物的彻底销毁处置。     

催化分解臭氧的方法及催化剂性能概述

臭氧作为一种有毒物质广泛存在于人们生活环境中,当其浓度超过0.06mg/m^3时,对人体就有害了。因此对臭氧的分解十分必要。本文介绍了多种分解臭氧的方法,并着重介绍 催化分解法。对各种氧分解催化剂的组成、制备方法及活性作一综述。     

昌吉州汞污染的分析

汞在常温下是有光泽的液态金属,在自然界多以化合物形式存在,矿产中主要以硫化物“辰砂”(HgS)形式存在。自然环境中除矿区附近外,汞含量都是很少的,例如大气中含量为0.02μg/m~3,土壤中含量在0.1mg/Kg 以下,河水汞含量在0.0001mg/L 以下;生物体中也都含有微量的汞。过多的含量大都是人为的污染。汞及其化合物都有毒。无机态的毒性较轻,有机态的特别是甲基汞毒性很强。水、食物中的汞可经口进入人体;大气中的汞可由呼吸道进入人体;汞还可经接触进入人体。大量汞摄入人体可引起急性中毒;微量汞长期进入人体,经蓄积到达一定程度时,才出现中毒症状。由于汞对神经有毒害,所以汞中毒晚期会出现运动失调、神经紊乱乃至死亡等严重后     

"绿色化学"在发展

从家用清洁剂、燃料、化妆品到胶水，都少不了使用具有污染作用的分子（物质）。法国室内控制质量观察所最近公布了一份调查报告。报告指出，在所调查的８０幢房屋和９所学校内，存在３种有毒物质：苯、四氯乙烯和三氯乙烯。该观察所的人员发现，这些房屋和学校室内空气中的这三种有毒物质的含量远远高于室外空气中这三种有毒物质的含量。可能的罪魁祸首是家用清洁剂（如清洗剂或去污剂）和装修用料（如粘合剂）。为了对付这种长期以来被低估的污染，化学工作者们想出了一些办法。但不幸的是，成本问题仍对人们广泛采取这些办法起着限制作用…     

地表水环境质量标准综述(二)——国外地表水环境质量标准、基准介绍及分析

对比分析了地表水环境质量标准、基准的国内外基本情况.着重分析了美国地表水环境质量标准的分类及与我国分类的异同点,从基本指标和有毒有害等指标两方面介绍了美国标准限值要求;从影响人体健康和影响水生生物两个方面介绍了美国水环境质量基准限值要求,其中影响人体健康方面涉及有毒有害物质、微生物、其他方面,影响水生生物涉及有毒有害物...     

美国企业有毒废物排放管理现状及对中国的启示

工业生产中产生的有毒废弃物是我们生活环境的一大危险,每个企业都有责任安全有效地处理其在生产过程中产生的有毒废弃物。美国环保署通过《有毒物质释放清单》的方式,要求工业、企业每年上报其有毒废弃物的产生、管理、排放的详细情况。并对所有数据进行收集、整理、统计、分析后在美国环保署网站上公布。美国这种敦促工业、企业披露其废弃物管理方式的做法可以让公众知晓企业的排污行为,也可以促使企业采取更负责任的方式管理有毒废弃物质。在新形势下,中国即将迎来新一轮区域性结构调整的浪潮,各地政府在产业结构调整的过程中,必须全面考量未来重点发展的行业的环境可持续性。因此,继续建立一个类似于TRI的公开、便捷的各业企业污染物情况数据库,满足各地政府管理地区发展的需要。     

现代厌氧反应器的现状与发展

回顾了厌氧反应器发展的三个阶段，对现代反应器的结构与应用情况进行了详细的介绍，认为目前主要研究与应用的热点是以现代反应器为代表的工艺；以膜技术和分阶段多相多级技术将是未来污水处理技术的主导技术；以复合反应器代表的工艺在处理城市生活污水，处理垃圾渗滤液以及有毒物质废水等将具有更多的优势。在能源资源短缺、环境日益恶化的今天，处理能力强、适用范围广、耗能少等优点的厌氧反应器有着广泛的应用前景与研究价值。     

航空接触器主触头输入端烧毁故障及原因分析

某型航空直流接触器在使用中出现主触头输入端烧毁故障。通过故障树综合分析，采用模拟烧毁试验手段对送检的接触器开展故障原因分析。结果表明，主触头输入端被烧毁的原因主要是接触器接触片表面氧化、接触处有污物，导致接触片与外接导线的接线片之间的接触电阻过大。在实际使用过程中，应结合定期检查工作，对接触器的螺母紧固、接触片的表面状态是否存在氧化发黑等情况进行外观检查，视情更换接触器，避免主触头接触片发生烧毁故障。     

焦炉煤气柜重大危险源评估技术方法及实例分析

以《危险化学品重大危险源监督管理暂行规定》为依据,通过实例对某15万m3焦炉煤气柜进行了危险化学品重大危险源辨识并分析其存在的危险有害因素,同时运用危险度分析、有毒物质泄漏扩散事故模拟分析、蒸汽云爆炸事故模拟分析等多种安全评价技术方法定性和定量描述煤气泄漏、爆炸事故发生的可能性及其危害程度,从而实现了危险化学品重大危险源定量风险评估的目标。     

农村水源地水质重金属健康风险评估研究

介绍了饮用水水源地中基因毒物质和躯体毒物质所致的健康危害的风险度计算模型,并根据雅安市雨城区农村水源地水质实测资料,进行健康风险评价与分析。结果表明:(1)基因毒物质由饮水途径所致健康危害的个人年风险按大小排列为Cr(VI)>As>Cd,而躯体毒物质的个人年风险按大小排列为Hg>Pb>Mn>Fe,但前者的影响远大于后者;(2)水源地中的3种基因毒物质所致健康危害的个人年风险,远远超过瑞典环保局、荷兰建设和环境部推荐的最大可接受水平1.00×10-6a-1,且Cr(VI)的健康风险危害超过国际辐射防护委员会(ICRP)推荐的最大可接受值5.00×10-5a-1,应将Cr(VI)视为本区饮水的优先治理污染物。     

硫化氢中毒的机制及其防治

本文综述了1958～1989年间对硫化氢中毒的研究成果。硫化氢是广泛存在于自然环境及某些工作场所的无色剧毒气体,其主要中毒机制是抑制细胞色素氧化酶,中断细胞的有氧氧化。预防性给予亚硝酸盐可减轻中毒症状,但对其中毒尚无有效的解毒剂。     

Ocean trench conservation

Considerable concern has been recently expressed in conservation circles about the potential threat to oceanic trench ecosystems. Here, the geological origin in environmental characteristics and biological significance of the trenches are reviewed. Each trench provides a unique and isolated habitat, consequently endemicity has been found to be high at the specific level in each trench that has been adequately studied. However, the remoteness from primary food sources greatly reduces the richness of the fauna. The physical instability of trench habitats deriving from their high level of seismic activity, will result in the organisms being pre-adapted to mechanical disturbance. The main threats are either direct through poisoning by toxic chemicals or indirect through the decoupling of the trench habitat from its primary food source, or reduction in oxygen levels caused either by eutrophication or reduction in flushing rates. Only direct threats are considered as being at all dangerous, and any incident would be restricted to a single trench system. these threats could be reduced by rerouting vessels carrying toxic cargoes and by improving the effectiveness of the London Dumping Convention. The internationally agreed criteria for the selection of sites for any proposed seabed disposal of radioactive waste exclude the use of trenches for this purpose.     

Approaches and initial findings of a state-sponsored research programme on population exposure to toxic substances

Summary Population exposure to toxic chemicals in the environment has become one of the most important, if not the most important, environmental issue of the 1980's. In response to finding high cancer mortality rates, the State of New Jersey organized an extensive program of research to determine public exposure to toxic substances in the environment. Three parts of that research are described. One focusing on toxic substances in the water has detected very low concentrations of many substances. These substances tend to be found in three distinct chemical groups: pesticides, light chlorinated hydrocarbons, and heavy metals. Gross pesticide contamination tends to occur in agricultural and forest areas; gross light chlorinated hydrocarbon pollution is in urban areas. The second component of the research is toxic substances in the air. Like the water studies, low levels of contamination have been found. Limited sampling to date has found groupings of ubiquitous organic chemicals in urban areas, two groups of specialized organic chemicals near industrial sites, and high lead levels near major highways. The third project is developing a computerized information bank about the use and disposal of 155 chemicals and will look for associations between industrial disposal practices and contamination of the environment.     

Trade union approach to control of toxic substances

Summary The paper deals with some of the problems associated with toxic substances in the work environment, it illustrates these by reference to case studies. It also looks at the involvement of Trade Unions in health and safety issues. It points out flaws and limitations of the present legislative measures; the need to detect toxic substances before they are introduced into the workplace. There is a strong argument for new procedures and regulations to control and license toxic substances; it sets out criteria advocated by Trade Unions towards achieving this. It shows how a whole new strategy has to be agreed to, a strategy that puts as its priority the health of the population as a whole.General Secretary of the Association of Technical and Managerial Staffs. A major Trade Union for scientist, technologists and technicians etc. in the UK.     

MAXIMUM CONTAMINANT LEVELS FOR TOXIC SUBSTANCES IN WATER: A STATISTICAL APPROACH1

ABSTRACT: A method to establish maximum contaminant levels or nondegradation standards for toxic substances in water is described. The method described is based on statistical outlier procedures which distinguish ubiquitous background levels of toxic substances from those concentrations significantly greater than background. Because this approach utilizes environmental data, it can calculate an interim maximum contaminant level which can help protect the public until sufficient health effects data are available to establish human health based maximum contaminant levels.     

Utility of laboratory streams for ecosystem toxicity studies

Laboratory stream microcosms have been used to study transport, fate, and effects of toxic substances in stream ecosystems. Several general concerns exist in utilizing laboratory streams in this way. We summarize some of the most important and difficult of these problems and endeavor to provide theoretical understanding, evaluation, and empirical approaches necessary for making laboratory stream ecosystem studies more useful in solving problems of toxic substance behavior in natural stream ecosystems. Well-designed laboratory streams and other microcosms are complex dynamic systems that can contribute to our understanding of the behavior of toxic substances. But such systems are far too complex and dynamic to be employed as bioassay, monitoring, or predictive tools, as individual organisms have been.     

Oversight of shale gas production in the United States and the disclosure of toxic substances

With the encouragement of shale gas production in the United States, governments have considered a range of legislative and regulatory proposals to manage health and environmental damages that may accompany extraction activities. Exceptions adopted by Congress to major federal environmental legislation have meant that individual US states have deemed it necessary to provide oversight through regulations to protect people and safeguard environmental quality. In responding, states have legal structures under which drilling firms may not need to disclose the toxic substances used in fracturing wells. Yet, with increasing numbers of drilling sites, more people are at risk from accidents and exposure to harmful substances used at fractured wells. To provide for meaningful health and safety protection, governments may need to reevaluate legal provisions offering trade secret protection for toxic substances used in fracturing.     

Priority screening of toxic chemicals and industry sectors in the U.S. toxics release inventory: a comparison of the life cycle impact-based and risk-based assessment tools developed by U.S. EPA

Life Cycle Impact Assessment (LCIA) and Risk Assessment (RA) employ different approaches to evaluate toxic impact potential for their own general applications. LCIA is often used to evaluate toxicity potentials for corporate environmental management and RA is often used to evaluate a risk score for environmental policy in government. This study evaluates the cancer, non-cancer, and ecotoxicity potentials and risk scores of chemicals and industry sectors in the United States on the basis of the LCIA- and RA-based tools developed by U.S. EPA, and compares the priority screening of toxic chemicals and industry sectors identified with each method to examine whether the LCIA- and RA-based results lead to the same prioritization schemes. The Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) is applied as an LCIA-based screening approach with a focus on air and water emissions, and the Risk-Screening Environmental Indicator (RSEI) is applied in equivalent fashion as an RA-based screening approach. The U.S. Toxic Release Inventory is used as the dataset for this analysis, because of its general applicability to a comprehensive list of chemical substances and industry sectors. Overall, the TRACI and RSEI results do not agree with each other in part due to the unavailability of characterization factors and toxic scores for select substances, but primarily because of their different evaluation approaches. Therefore, TRACI and RSEI should be used together both to support a more comprehensive and robust approach to screening of chemicals for environmental management and policy and to highlight substances that are found to be of concern from both perspectives.     

Preliminary study of physico-chemical treatment options for hospital wastewater

Hospital effluents are loaded with pathogenic microorganisms, partially metabolized pharmaceutical substances, radioactive elements, and other toxic substances. Such effluents if not treated properly can damage the natural environment and create a biological imbalance. This paper points out the areas of concern for hospital wastewater disposal and reports the findings of a limited physico-chemical study of treatment options for hospital effluents conducted at Christian Medical College and Hospital, Vellore, Tamil Nadu. The effluent collected was checked for conventional parameters and subjected to coagulation experiments. The raw and settled effluents were coagulated with FeCl(3), filtered and disinfected. Physico-chemical treatment seems to be an attractive option for the cost-effective disposal of hospital effluents. The results of this study call for further detailed study in this area.