净水剂中砷和汞的原子荧光测定法

目的 建立一种同时测定净水剂中砷和汞的方法.方法 采用消解样品后用双道氢化物发生原子荧光光谱法同时测定砷和汞.结果 方法的检出限砷和汞分别为0.15、0.07 μg/L;平均回收率分别为97.6%、93.6%,相对标准偏差分别为1.74%和2.31%.结论 净水剂中的砷和汞可以用双道氢化物发生原子荧光光谱法同时测定.     

微波消解-原子荧光法同时测定化妆品砷和汞含量

目的建立微波消解和氢化物发生-双道原子荧光光谱法同时测定化妆品中砷和汞。方法化妆品样品采用微波消解技术消解,优化仪器条件,选择负高压270 V,砷和汞空心阴极灯电流分别为80 mA和20 mA,用氢化物发生-双道原子荧光光谱法同时测定化妆品中砷和汞,并比较同时测定和分别测定化妆品中砷和汞含量的差异。结果在本实验条件下,砷的线性范围为0～20.00μg/L,相关系数为0.999 0,检出限为0.075μg/L,精密度为0.70%～3.84%,回收率为97.60%～99.52%;汞的线性范围为0～4.00μg/L,相关系数为0.999 4,检出限为0.030μg/L,精密度为0.72%～2.74%,回收率为91.00%～99.30%。氢化物发生-双道原子荧光光谱法同时测定和分别测定化妆品中砷和汞的含量差异均无统计学意义(P0.05)。结论采用本方法同时测定化妆品中砷和汞,精密度、准确度较好,检出限能满足分析要求,操作简单,可提高日常检测效率。     

原子荧光光谱法同时测定感冒冲剂中的砷和锑

介绍了一种氢化物发生—双道原子荧光光谱法同时测定感冒冲剂中砷和锑的方法。进行了实验条件的最佳化选择 ,探讨了共存离子对砷和锑测定的干扰和消除方法。在最佳工作条件下 ,砷和锑的检出限分别为 0 0 90 3μg/L和 0 0 5 78μg/L ,相对标准偏差分别为 2 0 1%和 1 39% ,砷和锑的样品测定回收率分别为89 2 %～ 97 8%和 90 8%～ 10 1 4 %。     

保健食品中砷和硒同时测定方法的研究

目的：建立同时测定保健品中砷和硒的方法。方法：湿法消解样品后用双道氢化物发生原子荧光光谱法同时测定砷和硒。结果：方法简单，准确，砷回收率为91．6％～100．7％，相对标准差0．43％～1．98％；硒回收率为90．8％～101.4％，相对标准差为0．46％～1．93％。结论：保健食品经湿法消解后，砷和硒可用双道氢化物发生原子荧光光谱法同时测定。     

氢化物原子荧光光谱法测定食品添加剂盐酸中砷

目的建立测定食品添加剂盐酸中砷的氢化物发生原子荧光光谱法。方法样品直接取样加酸定容后,用AFS-920双道原子荧光光度计进行测定。结果在本法条件下绘制标准曲线0.00μg/L～20.00μg/L浓度范围内线性关系良好,相对标准偏差(RSD)为1.06%,检出限0.042μg/L,样品回收率为97.90%～101.20%,氢化物发生原子荧光光谱法测定结果与二乙基二硫代氨基甲酸银分光光度法测定结果差异无统计学意义。结论氢化物发生原子荧光光谱法测定食品添加剂盐酸中砷是一种准确、快速、简便的方法,适用于广泛推广。     

双道原子荧光光度计同时测定化妆品中砷和汞

[目的]建立双道原子荧光光谱法同时测定化妆品中汞、砷的方法。[方法]采用微波消解样品预处理技术原子荧光光谱法同时测定化妆品汞、砷的含量。[结果]汞、砷的含量分别在0.0～2.0μg/L、0.0～20.0μg/L的范围内,相关系数分别为0.9992、0.9998,检出限分别为0.0022、0.018μg/L,相对标准偏差分别为6.67%、3.24%,回收率分别在97.3%、101%之间。[结论]微波消解-双道原子荧光光光谱法同时测定化妆品中的汞和砷是可行的。     

水中砷和硒的AFS-930型双道原子荧光光度计同时测定法

目的探讨应用AFS-930型双道原子荧光光度计,同时测定水中砷、硒的技术。方法用5%盐酸和5%硫脲-5%抗坏血酸混合试剂处理样品,并以0.2%氢氧化钾和1%硼氢化钾为还原剂,在2%的盐酸介质测定砷和硒。结果砷、硒回收率均大于95%,相对标准偏差小于3%,砷、硒的检出限分别为:As 0.10μg/L,Se 0.20μg/L。结论该方法精密度大,回收率高,操作简单,是测定水中砷、硒的可靠方法。     

微波消解-氢化物发生原子荧光光谱法同时测定食品中汞和砷

目的:建立微波消解-氢化物发生原子荧光光谱法同时测定食品中汞和砷的方法。方法:食品样品经微波消解后,用氢化物双道原子荧光光谱法同时测定食品中汞和砷的浓度。结果:本法在汞浓度为0μg/L～1.0μg/L、砷浓度为0μg/L～10μg/L范围内有良好的线性关系,相关系数rHg=0.9998,rAs=0.9997,检出限为Hg:0.0002 mg/kg,As:0.005 mg/kg;相对偏差为Hg:1.2%,As:0.83%;回收率为Hg:85%～91%,As:94%～103%。结论:该方法具有简便、快速、灵敏度高等优点,适合日常批量检测。     

原子荧光光谱法同时测定水产品中砷和硒

目的建立氢化物发生-原子荧光光谱法同时测定水产品中砷和硒的方法。方法样品采用硝酸-硫酸-过氧化氢消解体系进行湿法消化,优化实验条件,利用氢化物发生-原子荧光光谱法同时测定水产品中砷和硒。结果砷的线性范围为0.48~10μg/L,r=0.999 9,回收率为97.35%~100.74%,相对标准偏差(RSD)为1.25%~3.28%;硒的线性范围为0.21/L~10μg/L,r=0.999 7,回收率为99.35%~101.32%,相对标准偏差(RSD)为1.33%~5.40%。结论测定方法简单快捷,结果准确,适合于水产品中砷和硒的同时测定。     

微波消解—双道原子荧光光谱法同时测定水产品中砷和汞

目的:建立微波消解—原子荧光光谱法同时测定水产品中砷和汞的方法。方法:采用微波消解方法,双道原子荧光光谱法同时测定水产品中砷和汞的含量。结果:砷与汞的线性范围分别为0.04~200μg/L,0.01~100μg/L;相关系数分别为r=0.9998,r=0.9999;砷回收率为95.7%~98.4%,相对标准偏差为1.75%~3.41%,检出限为0.04μg/L;汞回收率为92.5%~97.9%,相对标准偏差为1.77%~2.77%,检出限为0.01μg/L。结论:微波消解—双道原子荧光光谱法测定水产品中砷和汞,方法灵敏度高,操作简便快速,结果准确可靠。     

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.     

The occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

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.