在线固相萃取-超高效液相色谱-串联质谱测定饮用水中2,4-滴和灭草松

目的 建立在线固相萃取-超高效液相色谱-串联质谱测定饮用水中2,4-滴和灭草松的方法。 方法 水样加入内标后,经微孔滤膜过滤,按水样:纯水=1∶3比例混匀后直接进样,采用在线固相萃取-超高效液相色谱-串联质谱系统进行富集浓缩并测定。样品利用C₁₈固相萃取柱富集浓缩,利用C₁₈色谱柱分离待测物,采用乙腈-水-甲酸为流动相梯度洗脱,负离子模式下,多反应监测模式检测。 结果 2,4-滴在5.00～200 ng/L范围内,灭草松在 10.0～400 ng/L范围内均有良好的线性关系,线性相关系数(r)>0.9990。检出限分别为2 ng/L和3 ng/L,加标回收率分别为91.2%～95.4%和96.0%～104%。 结论 该方法操作简单,灵敏快速、准确可靠,适用于饮用水中2,4-滴和灭草松的痕量分析。     

饮用水中35种抗生素的超高效液相色谱-串联质谱测定法

目的建立饮用水中35种抗生素类药物的超高效液相色谱-串联质谱(UPLC-MS-MS)测定方法。方法水样经0.45μm膜过滤,采用HLB固相萃取柱对水样中的目标物进行富集净化,用12 ml甲醇洗脱,洗脱液氮气环境下吹至近干,5%甲醇水溶液定容至1 ml,上机分析。选择ACQUITY UPLC HSS T3色谱柱(2.1 mm×100 mm,1.8μm)用作色谱分离,0.1%甲酸水溶液-甲醇为流动相进行梯度洗脱,质谱采用正离子扫描多反应监测(MRM)模式。结果在0.1~100μg/L的范围内,所得35种目标分析物的回归方程均具有良好的线性关系。方法的检出限为0.02~1.40 ng/L,定量下限为0.08~4.46 ng/L,加标回收率为63.0%~127.1%,RSD为0.6%~20.3%。结论该方法操作简单、快速,准确度和精密度均较高,适用于饮用水中35种抗生素的同时检测。     

饮用水中双酚A的固相萃取-高效液相色谱-电喷雾电离串联质谱测定法

目的建立固相萃取-液相色谱-电喷雾电离串联质谱测定饮用水中双酚A的方法。方法水样用SEP-PAKC18进行富集,甲醇淋洗,旋转蒸发浓缩后,采用高效液相色谱-负离子电喷雾电离串联质谱法测定。结果双酚A在5～100ng/ml线性范围内,得到回归方程y=6796.61x-8655.64,相关系数为0.9992,检测限(S/N=3)为0.0075ng/ml,定量下限(S/N=10)为0.025ng/ml。该方法的平均回收率为83.46%～94.00%,RSD为3.06%～4.60%。结论该方法简便、准确、快速,适用于水中双酚A的检测。     

固相萃取-液相色谱-串联质谱法测定水中的6种雌激素

目的建立水中6种雌激素的固相萃取-液相色谱-串联质谱检测方法。方法利用固相萃取前处理技术,液相色谱串联质谱的方法测定水中6种雌激素。液相色谱选择C_(18)色谱柱作为分离柱,甲醇、乙腈和水作为流动相梯度洗脱,串联质谱多反应监测模式进行检测。实验方法优化了质谱条件、液相色谱条件和固相萃取前处理条件。应用该方法测定了10份自来水样品。结果 6种雌激素在0 ng/L~5 000 ng/L时呈良好的线性关系,相关系数0.995,定性检出限为8.68 ng/L~103 ng/L,回收率为80.3%~93.0%,相对标准偏差(RSD)均≤15.5%。结论本方法不但可以同时测定水中6种雌激素,而且具有灵敏度好、选择性好、准确度高等优点。     

膜式固相萃取-超高效液相色谱-质谱联用法测定饮用水中11种有机磷酸酯阻燃剂

目的 建立膜式固相萃取-超高效液相色谱-质谱同时测定生活饮用水中11种有机磷酸酯类阻燃剂(OPFRs)的检测方法,并用于苏州地区饮用水中11种OPFRs的检测。方法 水样经膜式固相萃取后,采用超高效液相色谱-质谱多反应离子监测(MRM)分离检测,外标法定量,并对2021年8月份苏州78份水样中的OPFRs进行定量检测。结果 11种OPFRs线性关系良好,相关系数都在0.99以上,空白水样加标10 ng/L回收率为25.1%～105.0%,相对标准偏差为2.6%～19.2%。该膜式固相萃取-超高效液相色谱-质谱联用法可用于饮用水中11种有机磷酸酯阻燃剂的定量检测,苏州地区饮用水中OPFRs主要有TMP、TEP、TCEP和TCPP,水源水、市区出厂水、县级市出厂水、二次供水和末梢水OPFRs平均浓度分别为15.9 ng/L、205.1 ng/L、154.4 ng/L、13.9 ng/L和11.0 ng/L。不同水样类型中OPFRs(TPhP、TDCPP、TEHP、EHDPP除外)检出浓度差异有统计学意义(P <0.05)。结论 该方法前处理效率高,准确性好,灵敏度高,可应用于饮用水中...     

饮用水中12种抗生素残留的固相萃取-超高效液相色谱-串联四极杆飞行时间质谱快速测定法

目的建立了饮用水中12种抗生素残留的固相萃取(SPE)-超高效液相色谱-串联四极杆飞行时间质谱(UPLCQTOF)快速测定法。方法水样经过HLB小柱浓缩萃取之后以ACQUITY UPLC BEH C18色谱柱(100 mm×2.1 mm,1.7μm)为分析柱,以乙腈-0.1%甲酸溶液为流动相进行梯度洗脱;质谱采用高分辨质谱、正离子模式,以精确质量数和二级特征离子定性,以准分子离子峰面积定量。结果在0.1~500 ng/L的线性范围内,所得12种抗生素的回归方程均呈较好的线性关系,r0.99;该方法的检出限为0.018~6.0 ng/L,定量下限为0.06~20 ng/L,回收率为65.4%~84.7%,RSD为4.5%~11.7%。结论该法操作简单、快速、准确、灵敏、适用于饮用水中抗生素的快速筛查测定。     

在线固相萃取-超高效液相色谱-串联质谱测定饮用水中10种有机磷阻燃剂

目的 建立在线固相萃取-超高效液相色谱-串联质谱(On-line SPE-UPLC-MS/MS)测定饮用水中10种有机磷阻燃剂的方法。方法 水样加入内标后，经微孔滤膜过滤后直接进样，采用在线固相萃取-超高效液相色谱-串联质谱(On-line SPE-UPLC-MS/MS)系统进行富集浓缩并测定。样品利用C₈固相萃取柱富集浓缩，利用C₁₈色谱柱分离待测物，采用乙腈-水-甲酸为流动相梯度洗脱，负离子模式下，多反应监测(MRM)模式检测。结果 10种有机磷阻燃剂在一定范围内均有良好的线性关系，线性相关系数(r)>0.990。检出限为0.6～5.5 ng/L,低、中、高3种级别质量浓度的加标回收率分别为64%～106%、83%～104%、85%～99%。结论 该方法操作简单，灵敏快速、准确可靠，适用于饮用水中10种有机磷阻燃剂的痕量检测。     

全自动固相萃取-高效液相色谱-串联质谱法测定水中16种喹诺酮类抗生素

目的采用全自动固相萃取-高效液相色谱-串联质谱联用技术,建立水中16种喹诺酮类抗生素的分析方法。方法样品经MCX固相萃取柱富集、甲醇洗脱,以液相色谱-串联质谱-多反应监测模式(MRM)定性和定量分析。结果本法线性范围5.0~400.0 ng/L,检出限0.4~4.2 ng/L,定量限为1.2~12.6 ng/L,回收率为77.4%~113.2%,相对标准偏差(RSD%)为2.99%~8.52%。结论本法灵敏度高、重复性好,适用于水中16种喹诺酮类抗生素的检测。     

超高效液相色谱-串联质谱法测定水体中微囊藻毒素

目的建立测定水体中微囊藻毒素的超高效液相色谱-串联质谱分析方法。方法通过固相萃取富集净化,采用超高效液相色谱-串联质谱测定水中微囊藻毒素-LR。结果该方法检出限为0.04μg/L;线性定量范围为10～1 000μg/L,平均回收率为97.20%,平均相对标准偏差为4.71%。结论本文建立的超高效液相色谱-串联质谱法为水质微囊藻毒素监测提供了一种快速、准确、灵敏的分析方法。     

固相萃取-超高效液相色谱-串联质谱法同时检测消毒产品中的4种抗生素

目的建立固相萃取-超高效液相色谱-串联质谱法同时检测消毒产品中的4种抗生素(氯霉素、甲砜霉素、氟甲砜霉素和甲硝唑)。方法样品经40 mmol/L盐酸溶液提取,MCS固相萃取柱富集净化,乙酸乙酯洗脱氯霉素类抗生素,5%氨水甲醇洗脱甲硝唑,超高效液相色谱-串联质谱仪进行分析。结果标准物质在0 ng/ml~5.0 ng/ml时,方法的线性关系较好,相关系数(r)≥0.998;方法的检出限为0.003 ng/ml~0.01 ng/ml,定量限为0.01 ng/ml~0.02 ng/ml;4种抗生素的加标浓度为0.187 5 ng/ml~0.875 ng/ml时,回收率为70.40%~121.96%,相对标准偏差(RSD)为1.61%~9.30%。在10份消毒产品的检测中,检测到甲硝唑的存在,阳性检出率为20%。结论该方法的灵敏度高、选择性好、操作简单,适用于消毒产品中氯霉素、甲砜霉素、氟甲砜霉素和甲硝唑的同时检测。     

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.