吹扫捕集-气相色谱-质谱法测定饮用水中27种挥发性有机物

目的采用吹扫捕集-气相色谱-质谱法建立同时测定27种生活饮用水中挥发性有机物的方法,为制定相应的国家标准提供实验参考。方法利用吹扫捕集-气相色谱-质谱法联用技术,全扫描方式(SCAN)进行质谱定性,选择离子(SIM)内标法定量,测定生活饮用水中27种挥发性有机物。通过色谱条件优化,并对吹扫、解吸和烘焙等样品前处理条件的考察,建立了饮用水中27种挥发性有机物的吹扫捕集-气相色谱-质谱法测定方法。结果各待测组分的线性范围在0~40μg/L之间,相关系数r0.996,相对标准偏差(RSD)在2.85%~13.5%之间,样品平均加标回收率为91.5%~117.3%,检出限为0.04μg/L~0.50μg/L,定量限为0.14μg/L~1.7μg/L。结论该方法简单快捷,灵敏度高,回收率好,各分析组分之间无干扰,且用于实际水样的检测结果令人满意,适用于27种生活饮用水中挥发性有机物的同时检测。     

同位素稀释技术结合HPLC-MS/MS法测定饮用水中丙烯酰胺的研究

目的 建立生活饮用水中痕量丙烯酰胺的液相色谱-三重四级杆串联质谱法(LC/MS/MS).方法 样品加入同位素内标后,经用ProElut LLE+液液萃取柱富集,甲醇洗脱,用LC/MS/MS检测.结果 方法的检出限为0.006μtg/L,定量限0.02 μg/L,对超纯水和出厂水的加标试验,丙烯酰胺的回收率为92.0％～98.0％,相对标准偏差(RSD)为2.1％～7.2％,丙烯胺标准液在2～300 μg/L范围内线性关系良好,相关系数r=0.9995.结论 该方法准确、快速、灵敏,符合生活饮用水中痕量丙烯酰胺的检测要求.     

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0.00041～0.38000μg/L,定量限0.0014～1.2500μg/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。     

吹扫捕集-气质联用技术测定饮用水中痕量环氧氯丙烷

目的建立测定饮用水中痕量环氧氯丙烷的吹扫捕集-气相色谱/质谱联用检测方法。方法利用吹扫捕集技术,通过对吹扫温度、吹扫时间、解析温度、解析时间等参数进行优化,对水中痕量环氧氯丙烷进行富集、解析,并经DB-624毛细管色谱柱分离,采用选择离子模式(single ion monitoring,SIM)进行检测,提取特征离子定量分析。结果饮用水中环氧氯丙烷在0.122 5~12.25μg/L的浓度范围内线性好,线性相关系数r为0.999 7,本法检出限为0.02μg/L,添加水平为0.122 5~6.125 0μg/L时,测得环氧氯丙烷的加标回收率在91.0%~105.4%,重复测定6次,RSDs为1.7%~5.7%。结论本方法简单、灵敏度高、准确、重现性好,适合饮用水中痕量环氧氯丙烷的测定。     

碳纳米管固相萃取气相色谱-质谱法测定饮用水中N,N-二甲基亚硝胺

目的建立以碳纳米固相萃取测定饮用水中二甲基亚硝胺的气相色谱-质谱(GC-MS)检测方法。方法饮用水中N,N-二甲基亚硝胺经多壁碳纳米管柱浓缩富集,用二氯甲烷洗脱后,用GC-MS法测定,D_6-N,N-二甲基亚硝胺内标法定量。结果 GC-MS法测定N,N-二甲基亚硝胺线性范围为10.0μg/L~1 000μg/L,相关系数为0.999 1,加标回收率为83.5%~93.3%,相对标准差为4.9%~8.3%,当饮用水取样量为250 ml时,本方法定量限为4.0μg/L,检出限为1.0μg/L。结论该方法简单、快速、灵敏,可用于饮用水中二甲基亚硝胺的检测。     

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.     

超高效液相色谱-质谱法同时测定生活饮用水中7种农药残留

目的 建立一种同时测定生活饮用水中莠去津、呋喃丹、甲萘威、仲丁威、2,4-滴、灭草松和五氯酚等7种农药残留的超高效液相色谱-质谱方法.方法 水样离心后加入同位素内标,直接进样,采用C18色谱柱分离,以甲醇-乙酸铵水为流动相进行梯度洗脱,多反应监测模式检测,同位素内标法定量.结果 该方法在0.5～50 μg/L质量浓度范...     

同位素稀释-气相色谱串联质谱法测定啤酒中4种亚硝胺类化合物

目的 建立啤酒中4种N-亚硝胺类化合物（N-亚硝基二甲胺、N-亚硝基二乙胺、N-亚硝基二丙胺、N-亚硝基二苯胺）的同位素稀释固相萃取-气相色谱串联质谱测定方法。 方法 样品经活性炭固相萃取小柱富集、二氯甲烷洗脱,洗脱液经氮吹浓缩定容后,采用INNOWAX毛细管色谱柱分离,多反应监测（MRM）模式检测,同位素稀释内标法定量。 结果 各物质在5 μg/L~200 μg/L范围内线性关系良好,相关系数均大于0.9995。方法的检出限为0.03-0.10 μg/L,定量限为0.10~0.33 μg/L。不同水平的加标回收率为72.1%~100.3%,相对标准偏差为1.5%~9.5%（n=6）。 结论 该方法操作简单,灵敏度和准确度高,适用于啤酒中4种N-亚硝胺类化合物的测定。     

饮用水中苯甲醚和8种苯系物的吹扫捕集-气相色谱-质谱联用测定法

目的建立同时测定生活饮用水中苯甲醚和8种苯系物(苯、甲苯、乙苯、对二甲苯、间二甲苯、邻二甲苯、异丙苯、苯乙烯)的吹扫捕集-气相色谱-质谱联用方法。方法采用吹扫捕集的方法对水中的苯甲醚和苯系物进行富集,解吸后进入气相色谱-质谱联用仪,经色谱柱分离后,质谱检测器检测测定。结果方法的线性范围分别为0.73~47.0μg/L(异丙苯)和0.78~50.0μg/L(其余8种化合物),检出限为0.16~0.23μg/L,回收率为84.0%~120%,RSD为0.6%~5.0%。结论该方法灵敏度高、重现性好、操作简单、无需有机溶剂,适用于饮用水中苯甲醚和8种苯系物的同时测定。     

气相色谱-质谱联用法测定饮用水中的环氧氯丙烷

目的建立液液萃取气相色谱-质谱仪测定生活饮用水中环氧氯丙烷的方法,以满足国标对环氧氯丙烷的限值要求。方法通过对萃取溶剂、盐浓度、p H值和气相色谱-质谱条件的优化,建立了液液萃取气相色谱-质谱仪测定生活饮用水中环氧氯丙烷的方法。取200 m L水样,用0.1M Na OH溶液调节p H至7后加入10 g氯化钠,振摇使全部溶解,用二氯甲烷20 m L分2次萃取并浓缩至1.0 m L。浓缩液经TG-5MS毛细管柱分离后,采用选择离子监测模式监测、定性与定量。结果环氧氯丙烷在0.50~20.0μg/L范围内线性关系良好(r=0.999 4),检出限为0.2μg/L(S/N=3),定量限(LOQ)为0.7μg/L。对实际水样进行分析,低、中、高3种不同浓度的加标回收率为85.8%~103.2%,相对标准偏差(RSD)为4.8%~6.8%。结论该方法灵敏度高、线性范围广、准确、简易,适用于生活饮用水中环氧氯丙烷的测定,易于在基层实验室推广应用。     

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.