固相萃取-气质联用法检测上海市不同水厂各处理工艺环节水中几种除草剂、杀菌剂和雌激素水平

目的 建立应用固相萃取-气质联用法定性定量检测饮用水中几种除草剂、杀菌剂和雌激素的方法.方法 采集不同水厂各工艺环节水样各1 L,每点设2个平行样,以XAD-2树脂富集水样中目标污染物,30%丙酮-甲醇洗脱,采用气相色谱-质谱联用仪(GC/MS)对目标污染物定性定量分析.结果 6种待测物质(莠去津、甲草胺、4-枯基酚、噻苯咪唑、β-雌二醇、乙炔雌二醇)标准曲线线性范围为0.1～10 μg/ml,R2为0.9915～0.9995,检出限为0.01～0.40 μg/L,加标回收率为74.0%～112.0%,相对标准偏差(RSD)为2.3%～14.8%.黄浦江水源的原水、混凝后水、沉淀后水和出厂水中均可检出莠去津(0.11～0.13 μg/L)、4-枯基酚(0.20～0.35 μg/L)、噻苯咪唑(0.96～1.66 μg/L)、β-雌二醇(1.02～1.32 μg/L)、乙炔雌二醇(0.92～1.46 μg/L),各水样中均未检测到甲草胺.长江水源水厂各水样中均未检出6种污染物.结论 本方法灵敏度高、选择性好,适合于饮用水中目标污染物的同时定性定量分析.黄浦江水源饮用水中上述污染物浓度明显高于长江水源饮用水.黄浦江为水源的饮用水中存在μg/L级的噻苯咪唑、β-雌二醇、乙炔雌二醇应该在今后的监测工作中引起重视.     

双柱定性气相色谱电子捕获检测器测定上海市饮用水中微量碘化物

目的 对目前国家生活饮用水标准检验方法中气相色谱测定碘化物的色谱条件、定性定量方法等进行改进和优化,并以该法测定上海市饮用水中碘化物含量.方法 先以气相色谱与质谱联用鉴定衍生化产物碘丁酮,再用双毛细管柱配合电子捕获检测器对碘丁酮进行定性定量分析,最后分别采集上海市以长江、黄浦江及其内河为水源的3家水厂原水和出厂水各100 ml测定水样中碘化物水平.结果 经质谱鉴定发现碘化物衍生化后生成碘丁酮存在2个同分异构体,即1-碘-2-丁酮和3-碘-2-丁酮.采用双毛细管柱定性分析显示,碘丁酮分离度好,整个色谱分离时间为19.33 min.选择响应值较高的3-碘-2-丁酮进行定量检测,方法线性范围为1～100μg/L,确定系数r2=0.9997;方法检出限为13 ng/L;样品加标回收率为97.68%～104.37%,相对标准偏差为2.14%～4.41%.该方法测定3家上海市不同水源水厂的原水和出厂水中碘化物含量结果发现,原水中碘化物浓度以黄浦江最高(15.14μg/L),内河次之(6.97 μg/L),长江最低(3.55μg/L);除水厂2出厂水中碘化物浓度下降外(水厂2原水中碘化物浓度为15.14 μg/L,出厂水中为1.81μg/L),水厂1和3均呈略微上升(水厂1和3原水中碘化物浓度分别为3.55、6.97 μg/L,出厂水中分别为5.92、9.62μg/L).所有水样经平行双样测定的相对偏差均≤9.73%.结论 改进后的方法灵敏度更高、定性定量更准确,适用于水中微量碘化物的分析.     

水果和蔬菜中灭蝇胺的液相色谱-串联质谱测定法

目的 建立水果和蔬菜中灭蝇胺的高效液相色谱-串联质谱(HPLC-MS/MS)测定法.方法 样品经乙腈提取,使用乙二胺-N-丙基硅烷(PSA)基质分散净化剂净化,采用LC -MS/MS多反应监测(MRM)正离子模式测定,外标法定量.结果 该方法在1～100 μg/L内呈线性关系,相关系数为0.9998,加标回收率为75.4％～95.6％,相对标准偏差为2.1％～6.1％,检出限为0.25 μg/kg,定量限为1.0 μg/kg.结论 该方法灵敏度高、快速、准确,适用于水果和蔬菜中灭蝇胺的检测.     

饮用水中氯化氰的吡啶-巴比妥酸分光光度测定法

目的 探讨饮用水中氯化氰的检验方法.方法 采用吡啶-巴比妥酸光度法测定饮用水中氯化氰,对溶液的pH值、显色剂的配比、样品稳定性、氯胺T的加入量、显色反应时间和最大吸收波长等进行优化.结果 该方法的线性范围为0～0.1 μg/ml,相关系数为0.999 4,回归方程为y=0.194x-0.033,检出限为0.003 μg/ml,测定下限为0.01 mg/L,相对标准偏差在1.5%～6.2%之间,回收率为92.9%～107.1%.结论 该方法准确、灵敏、简便、快速,满足《生活饮用水卫生规范》(2001)的要求.     

固相萃取高效液相色谱法检测水中二苯胺残留量

目的:建立固相萃取高效液相色谱法测定水中二苯胺残留量的方法。方法:样品经固相萃取后进行高效液相色谱测定。色谱柱为SUPELCO Discovery C185μm 250×4.6 mm,流动相为:甲醇:0.02 mol/L NH4AC(pH=4.2)=70:30(V/V),流速为0.8 ml/min,二极管阵列检测器,检测波长为280 nm。结果:该方法的线性范围为:0.050～10.0μg/ml;标准曲线线性良好,其回归方程及相关系数r为Y=348.4X-3.5,r=0.99999。检出限为:0.60μg/L;回收率在99%～103%之间,相对标准偏差小于2.0%。结论:该方法操作简便、快捷,是水中二苯胺残留量的快速而准确的检测方法。     

水源水中无机硫化物的离子色谱-脉冲安培测定法

目的 建立水源水中无机硫化物的离子色谱-脉冲安培测定法.方法 水样经0.22μm尼龙膜过滤后,进入配有IonPac AS7易极化阴离子专用分析柱和脉冲安培检测器的离子色谱系统,以100 mmol/L NaOH-250 mmol/L NaOAc-0.5%(V/V)乙二胺为淋洗液进行等度淋洗后,硫离子与其他阴离子分离后,经电位脉冲安培检测器进行检测.结果 在5～1 000μg/L线性范围内,硫化物的线性方程为r=0.325 4x-1.305 3,r=0.999 8,检测限为0.5μg/L,平均回收率为90.8%～96.7%,RSD为1.32%.结论 该方法具有操作简单,选择性好,灵敏度高,重复性好等特点,适用于水中无机硫化物的检测.     

全自动固相膜萃取-高效液相色谱法测定水源水中的16种多环芳烃

目的 建立全自动固相膜萃取结合高效液相色谱法测定水源水中的16种多环芳烃。方法 水样加入10%甲醇后上样,上样流速为100 ml/min,待测物经固相膜萃取后,采用二氯甲烷进行洗脱,浓缩后上机,梯度洗脱,C18色谱柱分离,DAD检测器检测,根据保留时间和峰面积进行定性定量分析。从色谱条件、溶剂置换条件和萃取液浓缩方式等对水中16种PAHs的全自动固相膜萃取-液相色谱方法进行了优化研究。结果 在0.05 μg/ml～5.0 μg/L范围内,相关系数r>0.999;16种多环芳烃的仪器检出限为0.28 ng/L～1.04 ng/L;对水源水样品进行3个浓度水平0.05 μg/L、0.5 μg/L和5.0 μg/L,平均回收率在29.4%～100.3%之间;相对标准偏差(RSD)为2.3%～9.2%。结论 本法自动化程度高,快速、灵敏、简单,适用于快速分析环境水样中的痕量多环芳烃。     

婴儿奶粉中维生素B1和B2的高效液相荧光测定法

目的 检测婴儿配方奶粉中低含量的维生素B1和维生素B2.方法婴儿配方奶粉中加入0.5%乙酸溶液沉淀蛋白、过滤进样,采用反相高效液相法,选用含35%甲醇+65%0.05mol/L醋酸钠溶液(pH=4.5)作为流动相,流量1 ml/min,经Zorbax SB-Aq 100%水相反相色谱柱分离,柱温为室温,维生素B1的激发波长(λer)为375 nm,发射波长(λem)为435 nm,以0.25 g/L碱性铁氰化钾溶液为柱后衍生剂,流量为0.3 ml/min,反应温度为室温;维生素B2直接进行荧光测定(λex=462nm,λem=522 nm).结果 方法的线性范围为10～1 000 μg/L,相关系数均为0.9999,维生素B1最低定量检出限为5.1 μg/L,方法检出限为1.5 μg/L,维生素B2最低定量检测限为4.7 μg/L,方法检测限为1.4 μg/L,平均回收率为86.5%～98.1%,相对标准偏差小于5%.结论 该方法简便快捷、灵敏,满足日常快速分析要求.     

水中10种抗生素的全自动固相萃取-超高效液相色谱-串联质谱测定法

目的建立生活饮用水及水源水中10种抗生素的全自动固相萃取-超高效液相色谱串联质谱(UPLC-MS/MS)测定法。方法在1 000 ml水样加入Na_2EDTA充分溶解过滤后经全自动固相萃取装置浓缩净化,利用Waters ACQUITY UPLC HSS T3柱进行色谱分离,以乙腈-甲醇(V∶V=1∶1)和0.2%甲酸溶液为流动相,正离子模式扫描,多反应监测(MRM)模式检测。结果该方法线性范围为10~500μg/L,相关系数均大于0.99。10种抗生素的检出限为0.01~0.03μg/L,回收率为62.4~119%,RSD均小于10%。结论该方法准确、灵敏、快速,适用于水中抗生素的检测。     

固相萃取高效液相色谱法测定血浆中亚甲蓝含量

目的:建立血浆中亚甲蓝检测的高效液相色谱方法.方法:采用Waters OASIS HLB固相萃取小柱对血浆样品中残留的亚甲蓝进行萃取富集,采用高效液相色谱法SUNFIRE C18柱(5 μm 4.6×250 mm);流动相:水/乙腈/乙酸钠/乙酸/EDTA:750 ml/250 ml/6.5 g/8 ml/54 mg;流速:1.0 ml/min;柱温:25℃;二极管阵列检测器:293 nm进行分离测定,外标法定量.结果:在0.05～1.5 μmol/L浓度范围,其线性关系良好,Y=342950X 4298,相关系数(r)≥0.999.RSD为2.1%～3.8%,回收率可达到95%～99%.最低检测浓度为0.04 μmol/L.结论:该方法具有准确、灵敏、快速、简便等特点,能够用于经亚甲蓝处理的血浆样品的检测.     

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.     

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.