塞曼效应石墨炉原子吸收光谱法直接测定乳汁铅

[目的]探讨塞曼效应石墨炉原子吸收光谱法直接测定乳汁铅的方法.[方法]样品不用前处理,采用标准曲线法,用基体改进剂以1∶4稀释后直接进样测定,并进行了质量控制分析.[结果]方法的线性范围为(0～150)μg/L.批内精度(RSD%)在2.1～6.0之间,批间精度(RSD%)在5.8～8.1之间,特征浓度是1.0 μg/L,检出限当3σ时是0.3μg/L,回收率在96.7%～103.9%之间.分析的血铅标准物质(SRM 955,美国标准物质局生产)值是(58.6±3.2)μg/L,与其参考值(57.0±5.0)μg/L比较,在误差范围内.[结论]方法灵敏、简单,准确度和精密度都符合要求.     

钼酸铵分光光度法测定水发产品中过氧化氢残留量

[目的]建立一种简便快捷测定水发产品中过氧化氢残留量的新方法.[方法]取适量水发产品浸泡液于25ml比色管,加5.0ml 2.4mmol/L钼酸铵溶液,定容混匀后于室温下放置15min, 330nm处测定吸光度.[结果]过氧化氢在0～24.0μg/mL浓度范围内线性良好(γ>0.9987),方法检出限为18mg/kg,样品加标回收率为96.0%～100%.与四氯化钛分光光度法比较差异无统计学意义(t=1.70, P>0.05).[结论]该法简便、快捷、准确,可作为水发产品中过氧化氢残留量测定的方法之一.     

饮用水中的亚氯酸盐、氯酸盐和溴酸盐的离子色谱测定法

目的 建立同时测定饮用水中亚氯酸盐、氯酸盐和溴酸盐的离子色谱法.方法 选择IonPacAS23色谱柱,淋洗液为4.5mmol/L Na_2CO_3-0.8 mmol/L NaHCO_3,流速为1.0 ml/min,进样量为250 μl,电导检测池温度为30℃,色谱柱温度为35 ℃,流动相瓶加压为40 kPa,抑制器抑制模式为自动再生模式,抑制器电流为25 mA.结果 在0～1 000.0 mg/L范围内,亚氯酸盐的线性方程为:y=0.009 6+1.600 0x,r=0.999 3,检出限为5μg/L;溴酸盐的线性方程为:y=0.003 2+3.184 7x,r=0.999 9,检出限为5μg/L;氯酸盐的线性方程为:y=0.001 8+1.788 9x,r=0.999 9,检出限为5μg/L.加标回收试验结果显示,该方法的平均回收率为89.0%～108.0%,RSD为0.21%～2.70%.结论 该法操作简单、快速、准确,灵敏度高、干扰少,适用于饮用水中亚氯酸盐、氯酸盐和溴酸盐的同时测定.

Abstract：

Objective To develop an ion chromatography (IC) for simultaneous determination of chlorite, chlorate and bromate in drinking water. Methods The IC separation was carried out with the IonPAC AS23 column by using 4.5 mmol/L Na_2CO_3-0.8 mmol/L NaHCO_3 at the flow rate of 1.0 ml/min. The injection volume was 250 μl.the temperature of conductivity detector cell and column were 30 ℃ and 35 ℃, respectively. The pressure upon the bottle of mobile phase was 40 kPa. The current of auto-regenerating suppressor was 25 mA. Results The results showed that in the range of 0 to 1 000 mg/L, the calibration equation for chlorite was y=0.009 6+1.600 0 x (r=0.999 3),for bromate was y=0.003 2+3.184 7 x (r=0.999 9),for chlorate was y= 0.001 8+1.788 9 x(r=0.999 9).The detection limit of chlorite,chlorate and bromate were all 5 μg/ L,the recovery rates were 89.0% -108.0% and the relative standard deviations (RSD) were 0.21%-2.70%. Conclusion The method is simple,fast,accurate, sensitive, little interference and is applicable to the simultaneous determination of chlorite, chlorate and bromate in drinking water.     

超高效液相色谱-串联质谱法测定奶茶中4种烷基酚类化合物

目的建立超高效液相色谱-串联质谱法测定奶茶中双酚A(BPA)、双酚S(BPS)、辛基酚(OP)和壬基酚(NP)的残留量。方法奶茶样品经过离心后,直接取上清液用固相萃取柱进行净化,然后用ZORBAX SB-Aq色谱柱(3. 0 mm×100 mm,1. 8μm)分离,再用甲醇和5 mmol/L乙酸铵溶液作为流动相进行梯度洗脱,最后注入到质谱仪中,以电喷雾负离子模式(ESI-)电离,多反应监测模式(MRM)进行检测。结果 BPA、BPS在2μg/L～100μg/L线性关系良好(r 0. 999),方法的检出限(S/N=3)为0. 3μg/L、0. 01μg/L,回收率为75. 0%～86. 7%,相对标准偏差(n=6)为1. 0%～5. 8%; OP、NP在10μg/L～500μg/L线性关系良好(r 0. 999),方法的检出限(S/N=3)为0. 7μg/L、0. 9μg/L,回收率为73. 4%～112. 0%,相对标准偏差(n=6)为1. 9%～5. 9%。结论该方法简单、灵敏、准确可靠,适用于奶茶中4种烷基酚的测定。     

液相色谱-串联质谱法检测生活饮用水中氯酸盐、溴酸盐和亚氯酸盐

目的建立生活饮用水中氯酸盐、溴酸盐和亚氯酸盐的液相色谱串-联质谱检测方法。方法水样经0.22μm亲水PTFE滤膜过滤后,采用Acclaim Trinity P1色谱柱分离,20 mmol/L甲酸铵和乙腈为流动相梯度洗脱,在电喷雾离子化(ESI-)、选择反应监测(SRM)模式下检测,外标法定量。结果氯酸盐、溴酸盐和亚氯酸盐的线性范围分别为0.20μg/L～20.0μg/L、1.0μg/L～100.0μg/L和20.0μg/L～1 000μg/L,相关系数达到0.999以上;方法检出限分别为0.06μg/L、0.30μg/L和6.0μg/L,方法定量限分别为0.20μg/L、1.0μg/L和20.0μg/L;在低、中、高3个浓度水平下加标,氯酸盐、溴酸盐和亚氯酸盐的回收率分别为89.7%～92.7%、94.4%～108.1%和89.0%～100.1%,日内与日间相对标准偏差(RSD)分别为1.0%～7.4%和0.8%～8.0%。结论该方法准确、快速、易操作,能满足饮用水中氯酸盐、溴酸盐和亚氯酸盐的日常检测要求。     

石墨炉原子吸收光谱法测定尿中锰

[目的]建立一种石墨炉原子吸收光谱法测定尿中锰的方法.[方法]尿样用硝酸溶液稀释后,直接用石墨炉原子吸收法测定.[结果]石墨炉原子吸收法测定尿中锰,灰化温度可达1200℃,原子化温度为2400℃.标准曲线的线性范围为0.00～20.00μg/L,方法的检出限为0.2μg/L.测定样品的相对标准偏差在2.1%～4.6%L间,回收率在90.9%～106.8%之间.分别用标准加入法和标准曲线法测定不同尿样中的锰,经统计学处理,两者测定结果无显著性差异.[结论]该方法操作简便、迅速,具有良好的精密度和准确度,可用于尿中锰的测定.     

超高效液相色谱-串联质谱法测定婴幼儿配方奶粉中氯酸盐和高氯酸盐

目的建立超高效液相色谱-串联质谱法(ultra-high performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)同时测定婴幼儿配方奶粉中氯酸盐和高氯酸盐的分析方法。方法氯酸盐-~(18)O_3和高氯酸盐-~(18)O_4加入到样品中,通过涡旋混合、提取、离心和过滤,收集滤液,待UPLC-MS/MS分析。流动相为20 mmol/L甲酸铵和乙腈。Waters Torus~(TM) DEA(2.1 mm×100 mm, 1.7μm)色谱柱用来分析高氯酸盐和氯酸盐。采用负电喷雾电离,多反应监测模式,内标法定量。结果氯酸盐和高氯酸盐分别在0.2～200μg/L和0.1～100μg/L范围内线性关系良好(R~20.999),方法检出限分别为0.35和0.12μg/kg,定量限分别为1.16和0.40μg/kg。在15.0、75.0和150μg/kg加标水平下,氯酸盐回收率为91.9%～102.8%,相对标准偏差为2.5%～4.4%(n=6)。在7.5、37.5和75.0μg/kg加标水平下,高氯酸盐的回收率为91.3%～106.3%,相对标准偏差为2.6%～3.9%(n=6)。结论该方法简便、快速、灵敏度高、准确性好,适用于各类复杂基质中高氯酸盐和氯酸盐的同时分析。     

石墨炉原子吸收法直接测定血铅及其不确定度分析

[目的]建立一种石墨炉原子吸收光谱法直接测定血铅的方法,并对其不确定度进行分析.[方法]血样用0.15%(V/V)硝酸溶液稀释后,直接用石墨炉原子吸收法测定.并依据JJF1059-1999,对各不确定度分量进行分析评定.[结果]石墨炉原子吸收法测定血铅的灰化温度为500℃.标准曲线的线性范围为0-100 μg/L,方法的检出限为3.2μg/L,测定样品的相对标准偏差在2.1%～4.9%之间,冻干牛血标准物质GBW09139e的测定值与标准值的相对误差为1.7%.对于血铅含量为153.6 μg/L的冻干牛血质控样,其扩展不确定度为6.2 μg/L(k=2).[结论]该方法操作简便、快速、准确,符合生物材料中有害物质测定规范要求,可用于血铅的测定.     

淋洗液在线发生-离子色谱法测定饮用水中的氯酸盐

目的采用淋洗液在线发生-离子色谱法测定饮用水中消毒副产物氯酸盐(Cl O-3)的浓度。方法选用Ion Pac ASl9色谱柱,以淋洗液自动发生装置在线产生的高纯度KOH作淋洗液,通过抑制型电导检测器进行检测,考察了淋洗液浓度、流速、电流量对分离氯酸盐(Cl O-3)的影响情况。结果在KOH淋洗液的浓度为20 mmol/L、流速为1.0 ml/min、电流量为50 m A、进样量为250μl的色谱条件下,Cl O-3与共存离子的分离效果良好,保留时间为9.067 min。该方法对Cl O-3的检出限为0.44μg/L,在浓度为5μg/L~800μg/L具有良好的线性关系(y=0.001 1x-0.007 3,r=0.999 1),精密度高(相对标准偏差RSD3.71%),加标平均回收率为87.36%~110.32%。结论该方法操作简单,分离效果良好,灵敏度高,重现性好,适合于饮用水中氯酸盐的测定。     

用离子色谱法同时测定生活饮水中溴酸盐、亚氯酸盐、氯酸盐

目的:建立能够同时测定生活饮用水中亚氯酸盐、氯酸盐和溴酸盐的离子色谱法。方法:选择Ion-PacAS19色谱柱,淋洗液为氢氧根淋洗液,流速为1.0 ml/min,进样量为500μl,电导检测池温度为30℃,色谱柱温度为35℃,抑制器抑制模式为自动再生模式,抑制器电流为87 mA。结果:在0μg/L～500.0μg/L范围内,亚氯酸盐的线性方程为:y=2.640x-0.027,r=0.9999,检出限为0.1μg/L;在0μg/L～100.0μg/L溴酸盐的线性方程为:y=1.342x-0.003,r=0.9999,检出限为0.5μg/L;在0μg/L～500.0μg/L氯酸盐的线性方程为:y=2.157x-0.043,r=0.9999,检出限为0.2μg/L。加标回收试验结果显示,该方法的平均回收率为99.7%～102.6%,RSD为1.16%～3.56%。结论:该法操作简单、快速、准确,灵敏度高、干扰少,适用于饮用水中亚氯酸盐、氯酸盐和溴酸盐的同时测定。     

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.     

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.