室内空气中总挥发性有机物测定的热脱附气相色谱法

目的:依据GB50325-2001《民用建筑工程室内环境污染控制规范》建立一种适用于室内空气中总挥发性有机物的测定方法。方法:居室空气中总挥发性有机物及标准溶液经Tenax TA吸附管吸附,经热脱附及HPVOC色谱柱分离后进入气相色谱仪检测。结果:空气中9种化合物测定方法线性范围宽,精密度好;最低检出限为0.2 ng～0.3 ng,RSD1.1%～4.4%,最低检出浓度(采样体积5.0 L计)为0.0002 mg/m3～0.0003 mg/m3。结论:采用热脱附-气相色谱方法建立室内空气中总挥发性有机物检测方法灵敏度高、操作简便、重现性好、准确可靠;54种有机化合物可作为室内空气中总挥发性有机物的测定时未识别峰的定性定量参考依据。     

气相色谱测定室内空气中的总挥发性有机物方法探讨

目的探讨气相色谱测定室内空气中总挥发性有机物含量的方法。方法使用不锈钢吸附管(内部填充200~300 mg 60-80目Tenax-TA吸附剂)吸附室内空气中总挥发性有机物及标准溶液,经热脱附和Restek色谱柱分离后进入气相色谱仪中检测。结果室内空气中苯、甲苯、乙苯等9种挥发性有机物测定方法线性范围宽、精密度较好,检出限为0.6~1.4 ng,RSD值为1.2%~4.5%;采样量为5 L时最低检出浓度为0.2~0.3μg/m3。结论热脱附联合气相色谱法测定室内空气中的总挥发性有机物灵敏度高,重现性好且数据准确可靠。     

工作场所空气中9种酯类化合物的检测

目的:建立工作场所空气中9种挥发性酯类化合物的Tenax-TA吸附采样、热脱附-气相色谱检测方法。方法:用Tenax-TA吸附剂管按工作场所采样方法采集空气中挥发性酯类化合物,经热脱附-气相色谱检测。结果:9种酯类化合物检出限为0.5 ng~2.6 ng,最低检出浓度0.0005 mg/m3~0.0026 mg/m3;(采样体积1.0 L)。除乙酸乙烯酯相关系数为0.9987,其余8种酯类化合物相关系数均大于0.999;9种挥发性酯类化合物在低浓度组热脱附效率为93.8%~103.7%,RSDs为5.0%~7.5%;高浓度组热脱附效率为98.5%~106.7%,RSDs为1.1%~9.2%;9种酯类化合物的穿透容量除乙酸乙稀酯和乙酸乙酯分别为0.6 mg、0.9 mg外,其余均大于1.0 mg;稳定性试验中,9种酯类化合物在15 d内损失率为损失率小于10%。结论:该检测方法可用于工作场所空气中挥发性酯类化合物检测。     

工作场所空气中2-二乙氨基乙醇气相色谱测定方法的研究

[目的]建立工作场所空气中2-二乙氨基乙醇气相色谱测定方法。[方法]采用活性炭管吸附空气中2-二乙氨基乙醇,经二硫化碳解吸后气相色谱仪检测。[结果]本研究方法测定空气中2-二乙氨基乙醇线性范围5.0~200μg/ml,相对标准偏差(RSD)2.6%~6.4%,回归方程Y=5.34X-7.32,r=0.9998;方法最低检出浓度0.23mg/m(3采样体积3L计),解吸效率86.1%~92.8%,相对标准偏差1.9%~5.8%;穿透容量(BTV)6.57mg;2-二乙氨基乙醇室温放置5d,下降率9.5%;采样效率>90%。[结论]建立了工作场所空气中2-二乙氨基乙醇气相色谱测定方法,具有灵敏度高、操作简便、重现性好、准确可靠,适合工作场所空气中2-二乙氨基乙醇的测定。     

吹扫捕集气相色谱-质谱联用测定水中挥发性有机物

目的:探讨水中挥发性有机物的测定方法。方法:采用吹扫捕集气相色谱-质谱联用(scan扫描方式)测定水中挥发性有机物。结果:在所建立的实验条件下,28种挥发性有机物在一定的浓度范围内呈线性关系,平均回收率在88.3%~114%之间,变异系数为3.2%~8.5%,检出限为0.002μg/L-0.038μg/L。结论:所建立的分析方法简便、快速、准确,可进行水中挥发性有机物的同时测定。     

地下水中54种挥发性有机物的搅拌棒吸附-热脱附/气相色谱/质谱测定法

目的建立搅拌棒吸附萃取(SBSE)-热脱附-气相色谱/质谱联用法测定地下水样中54种挥发性有机物(VOCs)方法。方法将涂有聚二甲基硅氧烷(PDMS)的搅拌棒置于20 ml水样中以1 500 r/min萃取20 min后热脱附-气相色谱质谱仪检测,并分别对影响SBSE萃取效率的条件进行优化。结果方法检出限为0.03~6μg/L,54种VOCs的线性相关系数为0.994 3~0.999 9,RSD范围在1.09%~5.02%(n=10),平均加标回收率在81.6%~99.6%(n=10)。结论方法简便快速,准确度和灵敏度高,检出限低,稳定性好,干扰小,线性范围宽,无有机溶剂污染,可满足地下水样中54种痕量VOCs的分析测定。     

热脱附-冷阱捕集-气相色谱-质谱法测定工作场所空气中50种挥发性有机物

目的 建立快速测定工作场所空气中50种挥发性有机物的分析方法。方法 优化热脱附参数，采用优化后的热脱附-冷阱捕集-气相色谱-质谱法对工作场所空气中50种挥发性有机物进行分析，验证方法性能指标，并应用于实际样品的检测。结果 目标化合物在5～200 ng范围内线性关系良好，相关系数r>0.995,方法检出限为0.02～0.65μg/m³(以采样体积为2 L计算),加标回收率为81.3%～105.0%,相对标准偏差为1.3%～9.8%(n=7);采用该方法对某厂两个工段的场所空气进行了采集与检测，共检出了9种目标化合物，浓度范围为2.2～50.7 mg/m³。结论 该方法处理简单，线性良好，灵敏度高，精密准确，可实现对工作场所空气中50种挥发性有机物的快速准确分析。     

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。     

工作场所空气中挥发性有机物的GC/MS检测技术研究

目的:建立工作场所空气中54种挥发性有机物的GC/MS快速测定方法.方法:采用活性碳管采集车间空气中挥发性有机毒物,用二硫化碳解吸后以DB-VRX为分离柱、气相色谱-质谱仪联用检测分析.结果:所有组分彼此完全分离,能同时予以定性确认和定量分析;54种挥发性有机物空气在一定浓度范围内线性关系良好,相关系数r≥0.99;最低检出限远低于职业化学中毒现场剂量水平,目标组分解吸效率在76%～102%.结论:本方法准确度高、操作简便、灵敏快速,适用于工作场所空气中挥发性有机物中毒的快速定性定量测定.     

吹扫捕集-气相色谱-质谱法测定饮用水中52种挥发性有机物

目的建立同时测定水中52种挥发性有机物的吹扫捕集-气相色谱-质谱联用方法。方法设定不同实验条件,优化吹扫温度、吹扫时间、吹扫气流速、脱附温度、脱附时间等吹扫捕集参数和色谱、质谱条件。在选定的实验条件下,样品中的被测物经吹扫、捕集、脱附后,再经色谱分离、质谱检测,以特征离子与内标离子峰面积比值定量。结果 52种挥发性有机物在0.4μg/L~40.0μg/L具有良好的线性关系,其相关系数均0.998,检出限为0.004μg/L~0.02μg/L,回收率为86.0%~110.0%,相对标准偏差为1.2%~10.0%。利用该方法对北京市范围内30件生活饮用水进行了检测,检出了三氯甲烷、四氯化碳、一溴二氯甲烷、二溴一氯甲烷、三溴甲烷和二甲苯,检出的组分均符合卫生标准要求。结论该方法准确度和灵敏度高,具有较好的重现性,适用于水中52种挥发性有机物的同时测定。     

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.