酚试剂分光光度法测定饮用水中甲醛

目的 建立测定饮用水中甲醛方法.方法 利用水溶液中甲醛与酚试剂反应生成嗪,嗪在酸性溶液中被高铁离子氧化成蓝绿色化合物,产生颜色与甲醛含量成正比的原理,采用酚试剂分光光度法对饮用水中的甲醛含量进行测定,并与AHMT分光光度法比较.结果 本方法的线性范围0.005～0.100 mg/L,检出限为5×10-4mg/L,RSD为1.02%～1.17%,样品加标回收率为96.4%～107.2%.结论 该法用于实际水样检测,结果满意.     

居室空气中甲醛的极谱测定法

目的建立用二阶导数单扫描极谱法测定居室空气中甲醛含量的方法。方法用去离子水作吸收液,用空气采样器采样,利用甲醛与盐酸苯肼反应生成甲醛苯腙,通过测定甲醛苯腙的二阶导数还原波测定甲醛的含量。结果该方法的相对标准差RSD为2.2%,回收率为97.1%～103%,线性范围0.050～0.250mg/L,检出限0.004mg/L。对16个样品分别用该法和国家标准方法测定,结果差异无统计学意义(P>0.1)。结论该法简便,快速,检出限低,重现性好,结果准确可靠,适于空气中甲醛含量的测定。     

饮用水中溴酸盐的离子色谱测定法

目的建立并优化离子色谱法测定饮用水中溴酸盐含量的方法。方法采用大体积进样,离子色谱法梯度淋洗测定饮用水中痕量溴酸盐,并实现饮用水中多种阴离子同时测定。结果该方法对溴酸盐的检出限为0.2μg/L,在1～100μg/L范围内具有良好的线性关系(r=0.999 8),精密度高(RSD<1.0%)样品的加标回收率为95.4%～105.5%,可实现5种阴离子同时测定。结论该方法操作简便、快捷、灵敏度高,适合饮用水日常检测的需要。     

液/液微萃取-气相色谱/三重四级杆质谱联用法测定饮用水中11种多氯联苯研究

目的:建立一种快速、灵敏、准确的同时测定饮用水中11种痕量多氯联苯(PCBs)的液/液微萃取-气相色谱/三重四级杆质谱(GC-QqQ-MS/MS)联用分析方法。方法:水样采用液/液微萃取法进行富集,在HP-5MS色谱柱(30 m×0.25 mm i.d.×0.25μm)上,以高纯氦气(99.999)为载气,不分流进样,采用EI源以高纯氮气(99.999%)为碰撞气在多反应监测(MRM)模式下进行检测。结果:11种PCBs在5.0 ng/L～500.0 ng/L范围内具有良好的线性(R20.99),检出限在0.29 ng/L～1.50 ng/L范围,最低定量限在0.97 ng/L～4.90 ng/L范围,RSDs在3.3%～14.9%范围,方法的富集倍数为53.1～167.4倍;在加标水平为8.0 ng/L、40.0 ng/L和200.0 ng/L时,其回收率分别在94.6%～117.8%、66.5%～108.3%、84.0%～114.3%范围。结论:本方法可用于饮用水中痕量PCBs的测定。     

免试剂离子色谱法测定饮用水中草甘膦残留量

目的:建立免试剂离子色谱法快速检测饮用水中草甘膦残留量的方法。方法:在氢氧根系统-免试剂离子色谱系统内,优化并评价了对水溶性农药草甘膦的检测条件和分析性能,并将其应用于生活饮用水的测定。结果:草甘膦的线性范围为0.045～2.700 mg/L,回归方程为Y=0.029C,r=0.9995,检出限为0.015 mg/L,平均加标回收率为95.5%～96.7%,平均回收率96.2%,相对标准偏差为0.927%(0.90 mg/L,n=11)。结论:方法简单、灵敏,适用于饮用水中草甘膦残留量的测定。     

流动分析仪测定饮用水中阴离子合成洗涤剂与挥发酚及氰化物的方法探讨

目的 探讨流动分析仪测定饮用水中阴离子合成洗涤剂、挥发酚、氰化物的方法。方法 按照流动分析仪的操作步骤，进行饮用水中阴离子合成洗涤剂、挥发酚及氰化物的检测。结果 该方法在阴离子合成洗涤剂0.1～0.8 mg/L、挥发酚0.002～0.03 mg/L、氰化物0.01～0.08 mg/L浓度范围内线性关系良好（r>0.9990）；低、中、高三种浓度水平加标，阴离子合成洗涤剂、挥发酚、氰化物回收率分别为92.0%～103.0%、85.0%～105.0%、88.0%～105.0%，相对标准偏差分别为2.59%～3.13%、5.07%～7.44%、2.90%～7.11%。结论 流动分析仪测定饮用水中阴离子合成洗涤剂、挥发酚及氰化物操作简便，检测快速，可满足于基层实验室大批量的饮用水测定。     

新型自动比色法测定饮用水中的铝

目的建立一种新型快速测定饮用水中铝的自动比色法,并评价其效果。方法在国家标准方法基础上,优化试剂剂型,简化操作步骤,对方法测量范围、精密度、准确度以及实际样品测定进行实验研究。结果方法线性范围为0.008~0.20 mg/L,相关系数(r)为0.9995,检出限为0.006 mg/L,RSD为0.42%~2.60%,自来水加标回收率为87.5%~102%,对铝质控样品的测定结果均在标准定值范围内,相对误差为0.46%~4.15%。采用本法测定饮用水中铝结果与国家标准方法结果基本一致。结论新型自动比色法测定饮用水中铝,快速、准确、精密度高,操作人员无需自行配制试剂,测试所需试剂和样品用量少,节约环保,适合在村镇集中式供水单位普及应用。     

微量分光光度法快速测定饮用水中硫酸盐

目的建立一种快速测定饮用水中硫酸盐的微量分光光度法。方法基于硫酸钡比浊法原理,采用自主研发的可自动进样、比色、计算、清洗的微量自动分析仪及其配套试剂盒,对饮用水中硫酸盐进行测定。结果方法的线性范围为5 mg/L~80 mg/L,相关系数(r)为0.997 8,检出限为2.66 mg/L,RSD1%,自来水加标回收率为89.5%~109.0%,对硫酸盐质控样品的测定结果均在标准定值范围内,相对误差为0.36%~0.91%。采用本法测定实际样品中的硫酸盐,其结果与国家标准方法基本一致。结论微量分光光度法测定饮用水中硫酸盐,操作简单快速、准确、精密度高,与国家标准比浊法相比,量程翻倍,试剂种类、样本用量及废液的生成大幅减少,更加环保,适合在村镇集中式供水单位推广使用。     

吹扫捕集/气相色谱-质谱法同时测定饮用水中58种挥发性有机物

目的 建立吹扫捕集/气相色谱-质谱联用(P&T-GC/MS)同时测定饮用水中58种挥发性有机物（VOCs）的方法。方法 应用吹扫捕集技术,水中58种VOCs 经DB - 624色谱柱分离,GC/MS选择离子扫描模式进行分析,以保留时间和特征离子定性,内标法定量。结果 58种VOCs标准曲线的线性关系均≥0.997（环氧氯丙烷为0.985除外),方法检出限0.00041～0.38000 μg/L,定量限0.0014～1.2500 μg/L,回收率75.5%～117.9%,精密度0.6%～12.1%。应用该方法测定20份不同水样,结果分别检出28种痕量VOCs。结论 本方法简单,快速,灵敏、准确,适用于饮用水中多种VOCs的同时检测。     

离子色谱法同时测定饮用水中三价铬与六价铬分析方法验证

目的:确认离子色谱法同时测定饮用水中三价铬((Cr3+)与六价铬(Cr6+)分析方法可靠、准确,达到检测要求。方法:通过对系统适用性、检测限和定量限、精密度、准确度、线性范围的考察,证明该方法适用于使用目的。结果:Cr3+浓度在0.20 mg/L～8.0 mg/L;Cr6+浓度在4.0×10-4 mg/L～0.40 mg/L范围内,具有良好的线性关系(r=0.9994;r=0.9998);方法检出限Cr3+和Cr6+分别为0.139 mg/L、0.304×10-3 mg/L;精密度RSD均小于5%,平均加标回收率为86.7%～101.6%。结论:该方法灵敏度高,重现性好,能满足同时测定饮用水中三价铬与六价铬的分析要求。     

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.     

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.     

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.     

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.