尿中丁二烯代谢产物的生物检测方法

目的研究尿中丁二烯代谢产物1,2-双羟基-4-(N-乙酰半胱氨酸)-丁烷(DHBMA)和1-(N-乙酰半胱氨酸)-2-羟基-3-丁烯(MHBMA)的超高效液相色谱-质谱/质谱(UPLC-ESI-MS/MS)测定方法,对丁二烯暴露工人进行生物监测。方法尿液经1∶10稀释[100μl尿样+50μl混合内标应用液+850μl流动相A(15 mmol/L乙酸铵,p H=6.8)],涡旋混匀,过膜后直接进样,UPLC-ESI-MS/MS测定,工作曲线内标法定量。结果 DHBMA的定量检出限为0.50μg/L,尿中最低检出质量浓度为5.0μg/L,线性相关系数0.996,高、中、低浓度加标回收率为93%~106%;MHBMA的定量检出限为0.07μg/L,尿中最低检出质量浓度为0.70μg/L,线性相关系数0.998,高、中、低浓度加标回收率为84%~106%。结论 UPLC-ESI-MS/MS法测定丁二烯代谢产物DHBMA和MHBMA浓度的各项技术指标均能满足生物样品监测的要求,可用于职业场所工作人员的生物监测。     

职业接触二甲苯尿中甲基马尿酸生物限值的研究

选择不同暴露水平的二甲苯接触个体,检测个体二甲苯暴露浓度,同时采集当日工人班末尿样,对尿中二甲苯的代谢产物甲基马尿酸的含量进行测定,将二甲苯的外暴露空气浓度与体内甲基马尿酸代谢量进行回归分析,结合国外限值资料,提出适合我国职业卫生现状的甲基马尿酸生物限值的建议。接触工人在空气中二甲苯浓度为0～144.21 mg/m3时,班末尿中甲基马尿酸(MHA)与空气中二甲苯浓度之间存在良好相关性,肌酐校正回归方程为y(g/g肌酐)=0.0052x(mg/m3)+0.0112,r=0.731;比重校正回归方程为y(g/L)=0.0089x(mg/m3)-0.0259,r=0.793。将我国二甲苯职业接触限值50 mg/m3分别代入回归方程,推出工作班末尿中甲基马尿酸含量为0.271 g/g肌酐和0.419 g/L。依据我国二甲苯实际接触情况,参考国外相关标准和文献,建议我国职业接触二甲苯的代谢产物尿中甲基马尿酸的生物接触限值为班末尿0.3 g/g肌酐或0.4 g/L。     

甲苯接触者生物监测指标研究——尿中马尿酸和邻甲酚浓度

对32名职业接触甲苯、18名志愿受试者和77名非职业接触甲苯者的尿中马尿酸及邻甲酚的测定,发现在非接触者中,尿中马尿酸存在日间波动,邻甲酚排出量极少。工人和志愿者接触甲苯后,尿中马尿酸即开始上升,到脱离时达高峰,以后迅速下降,4小时左右降到正常本底水平,班末尿中马尿酸浓度与空气浓度相关(工人:r=0.64,志愿者:r=0.78)。尿中邻甲酚在低浓度接触者中,难以检出,但在高浓度接触时,班末尿中邻甲酚与空气浓度相关(工人;r=0.63,志愿者;r=0.65)。马尿酸和邻甲酚作为甲苯生物监测指标可结合使用。     

职业接触二甲基乙酰胺工人尿中甲基乙酰胺生物限值研究

目的 研制我国职业接触二甲基乙酰胺(DMAC)工人尿中甲基乙酰胺(NMAC)的生物限值.方法 选择3家氨纶生产企业201名接触DMAC工人,应用个体采样器采集工作周末工作日的车间空气样品,用气相色谱法检测个体DMAC接触水平,同时收集当日工人班末尿样,应用气相色谱法测定尿中NMAC浓度以评价DMAC接触工人内暴露水平.通过内外剂量的回归方程、百分位数和相对内暴露(RIE)指数计算,推荐我国职业接触二甲基乙酰胺工人尿中NMAC生物接触限值.结果 201名DMAC接触工人中接触浓度符合我国DMAC接触限值133名,占66.2％,接触浓度范围在0.40～300.12mg/m3,几何平均浓度为19.4 mg/m3.工作周末班未尿中NMAC浓度范围为1.30～189.42 mg/g Cr,几何平均浓度为23.7 mg/g Cr.尿中NMAC浓度与个体DMAC外暴露浓度有相关性(F=188.872,R2=0.487,P＜0.001),回归方程为log(NMAC mg/g Cr)=0.685+0.455 log(DMAC mg/m3).以我国DMAC职业接触限值PC-TWA为20 mg/m3推算,尿中NMAC浓度为18.92 mg/g Cr.当工作场所空气中DMAC＜20 mg/m3时,90％的工人尿中NMAC水平为23.9 mg/g Cr.按RIE指数推算的尿中NMAC为19.0 mg/g Cr.结论 参考国外DMAC生物接触限值标准,建议我国DMAC生物接触限值为工作周末班未尿中NMAC 20 mg/g Cr.     

锰职业接触工人生物标志物的研究

目的 探讨锰接触工人个体实际接触剂量与生物指标之间的关系,以寻找合适的早期生物学监测指标.方法 选择济南市某机车车辆厂电焊作业工人270名,收集其血液和尿液.原子吸收光谱法测定血锰、尿锰和个体锰接触剂量;高效液相色谱荧光法测定尿中高香草酸(HVA)和香草扁桃酸(VMA);对各指标进行相关性分析.结果 个体锰接触剂量(CTWA)为0.005 5～1.957 7mg/m3,平均浓度为(0.25±0.31)mg/m3;接锰工人尿锰浓度为0.011 2～2.447 2μg/mg Cr,平均(0.22±0.31)μg/mg Cr;血锰浓度为0.06～38.70 μg/ml,平均(3.94±6.66)μg/ml;尿HVA浓度为0.102～4.780 μg/mg Cr,平均(1.01±0.78)μg/mg Cr;VMA浓度为0.032～2.768 μg/mg Cr,平均(0.61±0.35)μg/mg Cr.个体锰接触剂量与血锰、尿锰、尿中VMA之间均无相关性(P＞0.05);个体锰接触剂量与尿中HVA呈负相关,差异有统计学意义(r=-0.168,P＜0.01).结论 血锰、尿锰、尿中VMA均不能作为评价锰接触的接触生物标志物;尿中HVA可以作为评价锰接触的效应生物标志物.     

8-羟基脱氧鸟嘌呤作为可溶性铬盐职业接触者生物标志物的研究

[目的]了解职业接触可溶性铬盐人群尿中8-羟基脱氧鸟嘌呤(8- OHdG)含量及其影响因素,探讨其作为职业接触人群生物标志物的可行性.[方法]2006年,选择济南市某铬盐生产企业114名重铬酸钾作业的健康劳动者作为接触组,以无毒物接触史的当地健康农民30名为对照组,测定2组人群尿液中8-OHdG水平与作业环境铬盐浓度,测定接触组外周血淋巴细胞DNA链断裂水平、红细胞与尿液中铬浓度.[结果]尿液中8-OHdG水平接触组为(1 240.494±1 603.918) μg/L,对照组为(468.871±908.460) μg/L(P<0.01);尿液中8-OHdG水平与空气中个体铬盐暴露水平、红细胞中铬浓度水平、外周血淋巴细胞DNA链断裂水平的相关系数(r)分别为0.333、0.230、0.396(P<0.01);多元线性回归分析显示,铬盐劳动者年龄、接触铬盐的年限、空气中铬盐浓度对尿液中8-OHdG水平影响显著.[结论]尿液中8-OHdG水平可以作为职业接触可溶性铬盐劳动者遗传损伤效应性生物标志物,可望用于职业接触可溶性铬盐劳动者生物监测及健康危险性的评价.     

液-质联用检测人尿中的苯巯基尿酸

目的建立人尿中苯巯基尿酸的检测方法,并实际测定职业接苯人群尿中苯巯基尿酸的浓度。方法尿样经酸化水解后,调适宜pH值,液液萃取苯巯基尿酸,经高效液相色谱分离,负离子模式电喷雾离子源质谱检测,选择分子离子峰m/z238,峰面积定量。结果该方法在5～320μg/L范围内线性关系良好,r=0.9994±0.0003,检出限1.2μg/L(S/N=3),回收率在86.8%～94.2%之间,日内与日间精密度相对标准偏差(RSD)均小于7%;用该法对55名职业接苯工人班末尿中苯巯基尿酸进行了检测,并对苯巯基尿酸浓度与空气苯浓度进行回归分析(r=0.8035,P0.05)。结论该方法快速、灵敏,选择性好,结果准确可靠,可用于职业接苯工人班末尿中的苯巯基尿酸的生物监测,亦可用于环境污染中苯吸收的评价。     

尿甲酸在职业病危害评价中作为甲醛生物标志物的意义

目的对车间空气中甲醛浓度和作业环境人群尿中甲酸含量进行测定,验证甲酸作为生物代谢物在接触甲醛的职业危害评价中的意义。方法对山东省生产人造板的某集团车间空气中甲醛浓度和作业人群尿中甲酸含量进行同步测定,采用Spearman法进行相关分析。结果车间空气中甲醛浓度与作业职工班末尿中甲酸含量呈正相关(r=0.46,P<0.05),与班末尿中甲酸增加量呈正相关(r=0.48,P<0.05)。推测与甲醛的MAC值相配套的甲醛接触工人班末尿中甲酸的生物阈限值,为尿中甲酸含量34.8 mg/g肌酐或甲酸增加量24.0 mg/g肌酐。结论尿甲酸可以作为接触甲醛职业危害评价中特征性较强的生物标志物。     

职业接触可溶性铬盐个体暴露与尿铬水平的相关性研究

目的通过对职业接触可溶性铬盐个体暴露与尿铬水平的相关性研究,探讨并提出可溶性铬盐职业接触者尿铬生物限值,为铬盐职业接触人群健康监护和危险性评价提供依据。方法通过流行病学横断面调查,以不同剂量铬盐接触的83名劳动者为研究对象,10名非铬盐接触的农民为对照,两组人群在年龄、性别和吸烟状况等方面相匹配,进行了个体铬盐暴露与班末尿铬含量的研究,并对二者之间的关系进行了分析。同时复习了对可溶性铬盐职业接触者尿铬生物限值的相关文献。结果对照组8 h个体空气铬连续监测浓度在0.00~0.08μg/m3之间,尿铬浓度经肌酐校正后在0.40~1.02μg/g肌酐之间。铬盐接触劳动者8 h连续空气个体监测浓度在0.10~287.00μg/m3之间,尿铬浓度范围在1.14~79.07μg/g肌酐。职业接触铬盐工人班末的尿铬浓度随个体铬盐暴露水平的增加而增加,两者具有相关性。其回归方程为尿铬浓度(μg/g肌酐)=4.16+236.86×空气中铬的浓度(mg/m3),尿铬与空气铬的浓度相关系数r=0.976。通过文献复习,美国政府职业卫生工作者协会(ACG IH)推荐的职业接触可溶性铬盐在与我国相同的时间加权平均阈限值0.05mg/m3下,尿铬生物接触限值为65.1μmol/mol肌酐(30μg/g肌酐)。结论职业接触可溶性铬盐工人班末的尿铬含量可以用来评价作业场所铬盐的接触情况。依据美国ACG IH推荐的生物接触限值以及本调查结果,作者提出连续工作5个工作日的工作周末/班末尿铬的推荐值为65.1μmol/mol肌酐(30μg/g肌酐)。     

二甲基甲酰胺生物接触限值的研究

目的研究我国职业接触二甲基甲酰胺(DMF)的生物限值。方法气相色谱法检测工作场所空气中二甲基甲酰胺浓度和作业工人班末尿中甲基甲酰胺(NMF)浓度,同时研究两者的相关性。结果 DMF接触者班末尿中NMF浓度与工作场所空气中DMF浓度有密切正相关(Y=0.3389X+3.0297,r=0.9986,P0.01)。根据作业场所空气中DMF的国家职业卫生标准,按回归方程推导出职业接触DMF的生物限值。结论 DMF接触者生物接触限值推荐值:班末尿中NMF为12.0 mg/gCr。     

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.