尿中砷的微波消解-示波极谱测定法

目的建立微波消解-示波极谱测定尿中砷的方法。方法采用微波消解处理样品,将砷全部还原为As(Ⅲ)后,在H2SO4-KBr-Se(Ⅳ)体系中用示波极谱法测定尿样中的砷,探讨最佳实验条件。结果该法线性范围为0～50μg/L(r=0.9998),检出限为0.67μg/L,RSD为1.44%,回收率为95.0%～103.0%。结论微波密闭消解样品,防止了试样中待测元素的损失,该法简便、快速、准确,适用于尿中砷的测定。     

食品水质中微量锌、锰、铜、铅示波极谱连续测定法

目的研究示波极谱连续测定食品水质中微量锌、锰、铜、铅.方法选用氨基乙酸-氯化钾-硫氰酸钾-盐酸作为底液,在该底液体系中4种微量元素在峰电位为-1.26 V、-1.55 V、-0.42 V、-0.29(VS.SCE)处产生稳定的络合吸附二阶导数极谱波,空白无峰出现.结果锌、锰、铜的检出限为0.01 mg/kg(L),铅检出限为0.02 mg/kg(L).锌、锰、铜浓度在0.01～0.8μg/g(ml)范围内与峰电流成正比,铅浓度在0.02～0.6μg/g(ml)范围内与峰电流成正比,r=0.998 3～0.9997.样品回收率96.6%～99.3%,RSD 1.3%～6.8%.结论该方法灵敏、准确、易于操作,可用于食品及水样中4种微量元素的连续测定.     

酚试剂-示波极谱法测定公共场所空气中甲醛

目的建立一种新的测定公共场所空气中甲醛方法。方法以0.005%酚试剂作吸收液,在10 g/L NaCl和10 g/L盐酸苯肼体系中,示波极谱法测定公共场所空气中甲醛。结果该方法线性范围在0.00~2.50μg/10 ml,关系良好,灵敏度高。用0.005%酚试剂作吸收液稳定性较好,最低检出质量0.02μg。精密度为1.26%~3.11%,在-870 mv处产生一灵敏极谱峰,加标回收率为95.2%~101.2%。结论用酚试剂—示波极谱法测定公共场所空气中甲醛方法简单、稳定性好、容易操作,适用于公共场所空气中甲醛的测定。     

示波极谱法测定空气中的痕量钇

空气样本经玻纤滤纸采集后,用0.1mol/L HCl 加热至80～90℃浸取2h,经过滤后,加铜铁试剂并调 pH 至9～10,用氯仿萃取钇—铜铁试剂螯合物,再用0.05mol/L HCl 反萃取,最后在 pH4.0～7.6的铜铁试剂—二苯胍—氯化铵体系中用示波极谱法测定。本法萃取—反萃取效率为90.2%,灵敏度为140.46μA/μg/10ml.线性范围为0.01～1.0μg/10ml,变异系数为2.5～8.1%,加标回收率为85.4～108.0%((?)=95.7%)。     

“单扫描极谱法测定食品中铅”国家标准方法研制验证报告

[目的]验证国标--单扫描极谱法测定食品中铅的可行性.[方法]运用GB/T5009.1-1996附录A和国家示波极谱议计量检定规程,对其线性关系及范围、检出限、精密度和准确度、稳定性进行验证.[结果]线性范围0.50～20μg铅,相关系数r=0.9999,检出限0.06μg铅,方法精密度0.32%,样品精密度5.1%～10.6%,回收率82.4%～108%,[结论]该法可适用于食品中铅含量测定.     

电化学法测定青椒中重金属镉

目的建立电化学法测定青椒中镉的最佳方法。方法用硫酸-过氧化氢消解法处理样品,用线性扫描溶出伏安法对青椒中镉进行测定,最佳的电化学参数为:起始电压为-1.2V,终止电压为-0.2V,富集时间为120s,缓冲溶液为醋酸钠(1mol/L)-氯化钠(0.2mol/L)。结果测定的镉含量在0.1⁰.9μg/mL浓度范围内呈良好线性关系,相关系数为0.999 1,检出限为0.01μg/mL,测定的相对标准偏差为0.97%,回收率在98.62%0.9μg/mL浓度范围内呈良好线性关系,相关系数为0.999 1,检出限为0.01μg/mL,测定的相对标准偏差为0.97%,回收率在98.62%¹01.10%。结论该方法操作简单,准确度好,灵敏度高,能够满足测定的要求。     

水中痕量铅、镉的巯基棉富集-火焰原子吸收光谱测定法

目的 探讨水中痕量铅、镉经巯基棉富集后进行测定的方法.方法 调节水样pH=7,使水样中痕量铅、镉同时富集在巯基棉柱上,再以4 ml 0.2 mol/L HCl溶液通过巯基棉柱进行洗脱、收集,以火焰原子吸收光谱法进行测定.结果 测定的回收率为96.6%～104.0%,RSD均小于5%.4种饮用天然矿泉水样中均未检测到铅、镉,而自来水和海水中铅的含量分别为1.56、0.43μg/L;镉的含量分别为0.62、0.07μg/L.结论 采用巯基棉富集技术,以火焰原子吸收光谱法可以测定不同的水样品中痕量的铅和镉,该方法快速、准确,精密度高.     

微波酸消解-原子吸收光谱法测定粽叶中7种金属元素的含量

[目的]建立微波酸消解-原子吸收法测定粽叶中铅、镉、铜、锌、锰、镍、铬7种金属元素的检测方法,为制定食品包装用粽叶的食品卫生标准提供依据。[方法]采用微波消解法和干灰化法分别处理不同称样量的粽叶样品以及两种标准物质（GBW07604杨树叶和GBW07605茶叶）,用原子吸收光谱法测定上述金属元素的含量。[结果]优化了微波酸消解样品前处理方法、样品量以及仪器测定条件,本方法对上述7种金属元素的检测限分别为0.58μg/L、0.032μg/L、0.014μg/ml、0.012μg/ml、0.013μg/ml、0.007μg/ml、0.20μg/L。称取0.2～0.3g样品进行微波酸消解,标准参考物质测定结果的相对误差小于6.7%,样品加标回收率为92.00%～104.0%,测定的相对标准偏差（RSD）为0.16%～4.9%。[结论]本方法简便快速,一次微波消解即可完成7种金属元素的测定。用于实际粽叶样品的测定,获得了满意的结果,可为制定食品包装用粽叶的食品卫生标准提供实验依据。     

化妆品等健康相关产品中BrO3-、IO3-和NO2-的离子色谱测定法

目的建立化妆品、食品及食盐中的BrO3-、IO3-和NO2-的离子色谱(IC)测定法.方法选用高容量柱IonPacAS9-HC,以9.0 mmol/L Na2CO3作淋洗液,流速1.3 ml/min,外接水自动抑制再生,0.5 g/L邻二甲氧基联苯胺盐酸盐溶液 5g/L溴化钾溶液 20%甲醇溶液 5.6%硝酸溶液作衍生剂,流速0.7ml/min,反应温度60℃,450 nm波长检测,样品预处理后进样分析.结果 BrO3-、IO3-和NO2-的线性范围分别为0.2～50、10～2500、1.0～150μg/L,r值分别为0.999 8、0.9997、0.999 4,检出限分别为0.008、0.02、0.10 mg/kg,RSD分别为0.1%～1.5%,0.4%～1.0%,0.2%～7.2%,回收率分别为93.3%～100.0%,96%～107%,92.0%～100.0%.样品的酸度和共存离子对测定无影响.结论该方法的线性范围广、准确、灵敏,可满足化妆品、食品及食盐样品中痕量BrO3-、IO3-和NO2-的测定.     

环境水样中痕量铜的浊点萃取-火焰原子吸收光谱测定法

目的建立环境水样中痕量铜的浊点萃取(cloud point extraction,CPE)-火焰原子吸收光谱(flame atomic absorption spectrometry,FAAS)测定法。方法样品在p H 9.5的条件下,加入0.4 ml的1 mmol/L 2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)溶液,0.1%氯化钙溶液0.1 ml,5%(W/V)Triton X-114溶液0.8 ml,40℃加热15 min后离心,采用火焰原子吸收光谱法进行检测。结果在2~240μg/L的线性范围内,所得回归方程为A=0.002 7c+0.024 6,r=0.995 8。以3倍信噪比计算,方法的检出限为0.62μg/L,富集倍数为36.58倍,平均加标回收率为96.28%~98.08%,RSD为1.67%~3.13%。结论该方法简单、灵敏,具有良好的重现性,适用于环境水样中痕量铜的测定。     

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.