铊在环境介质中的迁移机制及其对人体健康的影响

铊是一种高毒害性元素,随着我国矿产资源刚性需求不断增加,含有铊的低温铊、汞、铅、砷、锑、锌等矿床开采规模和力度也不断加大,铊污染所引起的环境问题与日俱增。通过地表地球化学过程,存在于岩矿中的铊会迁移到土壤、水体、大气及生物中,并通过食物链传输到人体中,最终对人体健康造成严重危害。     

铊的毒理学研究进展

铊是一种毒性高蓄积性强的重金属环境污染物，主要损害中枢神经，胃肠道和肾脏等。人们可通过受污染的空气、水、食物等途径受到低浓度铊的慢性危害。本文重点讨论了铊在机体内的代谢动力学，毒作用特点及其机理，以及铊的生殖毒性等方面的有关问题。     

含酚废水壳聚糖衍生物吸附法处理

随着石化、塑料等行业的发展,排放入环境的含酚废水也相应增加.酚类物质是一种细胞原浆毒,其毒性与细胞原浆中蛋白质发生反应,具有致癌、致畸、致突变毒性[1].鉴于清除环境水体中酚类污染物不仅涉及水生生物的生长繁殖,更涉及广大城乡居民的食品和饮用水安全.因此,研究高效的含酚废水处理技术,对环境保护和可持续发展有着极为重要的意义.壳聚糖作为一种天然高分子,资源丰富,价廉易得,环境相容性好,在废水处理中用作重金属离子络合剂以及絮凝剂方面具有独特优势[2].但壳聚糖存在水溶性差、分子量小、吸附架桥能力差等缺前,限制了其应用.本研究合成了完全水溶性的壳聚糖接枝共聚物,并以其作为吸附剂处理含酚废水,获得满意效果.     

环境介质中铊的检测及其影响因素研究进展

铊作为生物体非必需元素,广泛存在于环境中,已被列入我国优先控制污染物;其在环境中的富集过程、迁移转化行为,直接影响着其对生物体的毒性大小。笔者综述了环境介质中铊的前处理及检测方法,并通过分析氧化还原、络合和吸附-解吸作用对铊迁移转化的影响,重点探讨了水环境中铊的迁移转化过程及规律,以期为有效评估铊污染及防治提供科学依据。     

微生物在水体重金属污染治理中的应用

介绍重金属废水微生物处理技术的一般原理、研究现状及应用前景,指出了微生物处理技术的特点和优越性。     

重金属废水的危害及治理

论述了重金属废水的来源和危害 ,讨论了废水中微量元素的基本特性。介绍了重金属废水处理原则和技术方法。     

生物材料中铊的溶出伏安法检测

重金属铊 (Ｔｌ)是一种对人体有着明显毒害作用的元素 ,国内曾有过严重后果的病案报道[1] 。检测生物材料中铊 ,国内主要使用化学比色法、经典极谱法[2 ] 和原子吸收法 ,大都存在灵敏度低、操作繁冗、干扰因素多或难以普及等不尽人意之处。我们利用溶出伏安法富集并连续扫描分析同一样品多种元素的特点 ,将一罕见的急性混合型铅、铊中毒患者尿液、血液、粪便、头发等材料通过ＡＤ 2Ｂ型半微分极谱仪 ,在固体电极上实现了对铊的定性、定量溶出伏安法检测。一、材料与方法(一 )原理样品经酸加热无机化后 ,其中的阳离子Ｔｌ 在玻碳汞膜电极上富…     

一种小型生活废水处理利用装置的研制

目的研发一种小型生活废水处理利用装置以节约水资源。方法研制的小型生活废水处理利用装置的流程为消毒剂将水净化,消毒后的污水自身旋转,而后杂质沉淀分离,得到净化水。采集10份生活废水水样消毒处理后进行水质检测。结果该装置处理生活废水性能良好,10份水样处理后感官性状和常规微生物指标达到了GB5749—2006《生活饮用水卫生标准》要求。结论该装置构造简单、操作方便、经济实用。处理后的生活废水可用于冲厕及洗刷。     

土壤重金属污染

污染土壤的重金属主要包括汞、镐、铅、铬和类金属砷等生物毒性显著的元素,以及有一定毒性的锌、铜、镍等元素,主要来自农药、废水、污泥和大气沉降等.过量重金属可引起植物生理功能紊乱、营养失调.重金属污染物在土壤中移动性很小,不易随水淋滤,不被微生物降解,通过食物链进入人体后,潜在危害极大.     

计时电位溶出法测定痕量铊（Ⅲ）

计时电位溶出法测定痕量铊（Ⅲ）王银起铊是一种对人体危害较大的蓄积性毒物。可由开矿或燃煤工厂排出含铊的废水而污染水源〔１〕。铊的主要测定方法有有机溶剂萃取光度法和电位溶出法等〔１，２〕，多见于矿样、人发等材料的检测报道。而在水质分析中应用报道甚少。本文...     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.