离子色谱法检测石油醚中硫酸根离子

[目的]建立石油醚中硫酸盐的高效阴离子交换色谱抑制型电导检测方法.[方法]选用去离子水、石油醚按照1:1的体积比进行萃取后,取下清液水相过前处理小柱和过滤后进样分析.色谱条件为:高容量氢氧化物选择性色谱柱IonPac AS18阴离子分析柱,30 mmol/L氢氧化钾(KOH)淋洗液等度淋洗,配有连续自动再生微膜抑制器的电导检测器.[结果]方法检出限为0.03 mg/L,线性范围为0.2～20 mg/L和5～500 mg/L(可根据样品浓度选取不同的线性范围),相关系数r=0.999 8以上.平均加标回收率为91.2%～101.3%,连续进样重现性RSD小于2.2%.[结论]本方法操作简单、快速、灵敏,结果准确,选择性好,适用于石油醚中硫酸根离子的测定.     

抑制电导检测-离子色谱法测定人尿中硫氰酸盐

目的建立尿中硫氰酸盐的离子色谱测定方法。方法尿样经离心后,用纯水稀释10倍。经C18固相萃取柱净化,离子色谱仪进行分析。结果尿中硫氰酸盐在0.25~20.0 mg/L线性相关系数为0.9999,检出限为0.10 mg/L,定量限为0.30 mg/L,批内相对标准偏差(RSD)为4.67%~8.64%,批间RSD为5.44%~8.97%,加标回收率为91.5%~101.7%。结论本方法精密度高、线性关系好、准确度高、检出限低,适用于人尿中硫氰酸盐的测定。     

尿中13种邻苯二甲酸酯代谢物的高效液相色谱串联质谱测定法

[目的]建立同时测定人尿中13种邻苯二甲酸酯代谢物的高效液相色谱-串联质谱法. [方法]尿样经β-葡萄糖苷酸酶水解、阴离子交换固相萃取柱(Oasis MAX)净化后,经SB-phenyl RRHD柱分离,电喷雾电离质谱检测,同位素内标法定量. [结果] 13种代谢物在0.5～200 μg/L的范围内均具有良好的线性关系,相关系数均≥0.999,检出限在0.1～0.2 μg/L之间,回收率为93.7％～110.3％,相对标准偏差(RSD)均＜10％. [结论]建立的检测尿中13种邻苯二甲酸酯代谢物的高效液相色谱串联质谱法适用于尿样中邻苯二甲酸酯代谢物的含量测定和人群邻苯二甲酸酯暴露评估.     

原子荧光光谱法测定尿锑浓度

[目的]建立原子荧光光谱法测定尿锑浓度的检测方法. [方法]尿样经混合酸消化后,加入硫脲和抗坏血酸使5价锑还原为3价锑,再加入硼氢化钾还原生成锑化氢,由氩气载入石英原子化器中分解为原子态锑,在锑空心阴极灯发射光的激发下产生原子荧光,荧光强度与标准系列比较定量. [结果]尿锑浓度为0.0～10.0 μg/L的线性关系较好,相关系数为0.999 4～0.9999;最低检出限为0.06 μg/L;相对标准偏差为1.9％～2.4％;平均加标回收率为99.7％. [结论]建立的湿法消解-氢化物发生-原子荧光光谱法测定尿锑实用、快速、准确、灵敏度高、基体干扰少,便于推广运用,尤其适用于大批量人群职业健康体检尿锑的检测.     

柱前衍生-气相色谱法测定人尿中硫氰酸盐

目的建立采用2,3,4,5,6-五氟苄基溴(PFB-Br)进行柱前衍生,气相色谱法测定人尿中硫氰酸盐的方法。方法取20.0μL尿液,分别加入1.0 m L乙腈及100.0μL PFB-Br进行衍生反应,直接采用气相色谱仪检测。结果尿中硫氰酸盐的质量浓度在1.000~10.000 mg/L呈线性关系,线性相关系数为0.999 6,方法最低检出浓度为0.112 mg/L,最低定量浓度为0.411 mg/L(以20.0μL尿样计算);方法的加标回收率为97.22%~102.04%,批内相对标准偏差(RSD)为1.46%~5.10%,批间RSD为1.56%~5.35%。氢氰酸离子对测定有干扰,其余常见的无机离子如氯离子、硫酸根离子和硝酸根离子等对测定结果均无干扰。样品在4℃至少可保存15 d。结论该方法适用于人尿中的硫氰酸盐的测定。     

柱前衍生-高效液相色谱法测定人尿中硫氰酸盐

目的建立以五氟苄基溴作为柱前衍生试剂,高效液相色谱法测定人尿中硫氰酸盐的方法。方法尿样中硫氰酸盐与五氟苄基溴衍生后,经多孔层120EC-C18色谱柱分离,以乙腈:去离子水(60:40,V/V)为流动相,经高效液相色谱-紫外检测器检测,检测波长为212 nm。结果尿中硫氰酸盐质量浓度为0.05~10.32 mg/L时线性关系良好,线性相关系数为0.999;检出限为6.31μg/L,最低检出浓度为63.10μg/L(以尿样体积0.1 mL计);加标回收率为95.1%~102.9%;批内相对标准偏差(RSD)为0.9%~1.0%,批间RSD为0.9%~2.1%;在4℃样品可保存7 d。结论本法灵敏度高、特异性好、样品前处理简单,可用于职业人群尿中硫氰酸盐的测定。     

酸解萃取—气相色谱法测定尿酚之研究

用酸解萃取法处理尿样,经PBOB液晶柱分离,氢焰检测器定量,能分别测定尿中苯酚、邻甲酚、间甲酚和对甲酚。尿酚浓度在0～60mg/L范围内为直线相关,r=0.999。本法回收率为79.1％,最低检出限0.1mg/L尿.     

离子色谱法同时测定饮用水中七种阴离子的含量

目的:建立同时测定饮用水中7种无机阴离子含量的测定方法。方法:样品用0.2μm滤膜过滤后直接进样,离子色谱法同时测定氟化物、氯化物、亚硝酸盐氮、溴化物、硝酸盐、硫酸盐和磷酸盐。色谱柱为:IonPac AS19型阴离子交换色谱柱(4 mm×250 mm i.d)和IonPac AG19保护柱;检测方式为:抑制型电导检测器。结果:本法相关性好(r>0.9993),精密度高(RSD%<3.0),样品加标回收率为95.0%～103.7%,检出限分别为:F-:0.0015 mg/L;Cl-:0.0010 mg/L;NO2--N:0.0019 mg/L;SO42-:0.0012 mg/L;Br-:0.0018 mg/L;NO3-:0.0013 mg/L;HPO24-:0.0023 mg/L。结论:该方法操作简单、快速、准确、线性范围广,可满足大批量水样检测分析要求。     

吹扫捕集-气相色谱/质谱法测定水中二甲氧基甲烷

[目的]建立吹扫捕集-气相色谱/质谱检测水中二甲氧基甲烷的方法. [方法]利用吹扫捕集富集水中二甲氧基甲烷,解吸后用气相色谱/质谱法测定,选用特征离子外标法定量. [结果]方法在试验浓度范围内线性良好(r=0.9995),检出限为0.03 μg/L,回收率为95.2％～99.3％,相对标准偏差为2.18％～3.87％. [结论]该方法准确性好、灵敏度高,适合于水中二甲氧基甲烷的检测.     

丙烯腈作业工人尿硫氰酸盐水平及健康效应

[目的]调查接触低水平丙烯腈作业工人的尿硫氰酸盐浓度及健康效应,探讨其是否可作为低水平丙烯腈暴露的接触指标。[方法]选取某化工企业接触丙烯腈工人315名作为研究对象,进行常规职业健康检查,并采用吡啶一巴比妥酸比色法测定尿硫氰酸盐浓度。[结果]丙烯腈作业工人尿硫氰酸盐浓度呈正偏态分布,中位数为4．95mg／L,四分位间距为4．84mg／L。尿硫氰酸盐浓度与吸烟、饮酒及其他健康效应均未显示出统计学关联。[结论]尿硫氰酸盐含量不能作为低水平丙烯腈暴露的接触指标。     

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.