呼出苯和血苯作为生物接触指标的研究

对两皮鞋厂的３０名（男１１名，女１９名）苯作业工人，分别监测其呼出苯、血苯、尿酚浓度和车间空气苯以及呼出苯的毒代动力学观察。结果表明各指标间都有明显的正相关（Ｐ＜０．０１）和好的线性关系。班前呼出苯分别为０．０２６（停止接触４０ｈ）和０．１３６ｍｇ／ｍ３（停止接触１６ｈ）；血苯班前班后平均浓度分别为３．２ｌ和１０μｇ／Ｌ；班前班后血／气分配系数分别为６．６７和７．６０。１６ｈ衰减率达９９％以上。故以呼出苯和血苯作为职业性苯接触的生物监测指标，简便、灵敏、特异性好。     

吸烟对低浓度混苯作业男性工人淋巴细胞DNA的损伤

目的探讨吸烟对低浓度混苯（苯、甲苯、二甲苯）接触男性工人淋巴细胞DNA的损伤作用。方法采用单细胞凝胶电泳法检查了48名男性职工的外周血淋巴细胞DNA的损伤，并调查其吸烟情况。结果在非低浓度混苯接触的情况下，吸烟组与非吸烟组的淋巴细胞DNA损伤率差异无显著性，在低浓度混苯接触的情况下，吸烟组的细胞DNA损伤率（9．07％）高于对照组（5．00％），差异有显著性。结论吸烟和低浓度混苯联合接触可引起淋巴细胞DNA的损伤。     

微核试验和彗星试验观察职业性二甲基乙酰胺暴露的遗传损伤

[目的]观察二甲基乙酰胺（DMAc）对职业接触人群所产生的遗传损伤。[方法]用胞质阻断微核试验（CBMN）和彗星试验（SCGE）检测某氨纶企业DMAc接触工人（30名）及非接触DMAc的对照人员（30名）的外周血淋巴细胞DNA和染色体损伤。[结果]接触组微核率、微核细胞率、核分裂指数分别为（4．67±2．25）％。、（4．56±2．19）‰、（1．82±0．30）％。,对照组分别为（5．00±2．62）％。、（4．89±2．59）‰、（1．73士0．25）％。,两组的各指标间差异均无统计学意义（P〉0．05）。接触组彗星尾DNA百分比、细胞尾长、尾相分别为（4．76±2．63）％、（12．60±5．68）岍、（2．51±2．30）,对照组分别为（4．49±2．48）％、（11．77±5．01）um、（2．28±1．89）,各指标间的差异均无统计学意义（P〉0．05）。[结论]在本实验条件下,职业性DMAc接触人群外周血淋巴细胞的染色体和DNA未表现出遗传损伤。     

苯致染色体损伤与X线修复交叉互补基因1多态关系的研究

目的 探讨DNA损伤修复基因—X线修复交叉互补基因1(XRCCI)多态性与苯致外周血淋巴细胞染色体损伤的关系.方法 采用胞质分裂阻滞微核试验方法评价459名苯接触工人和88名非接苯对照组工人染色体损伤水平,应用聚合酶链反应-限制性片段多态性技术检测XRCCI第6外显子194密码子,第9外显子280密码子和第10外显子399密码子多态.结果 接苯组微核发生率(2.12‰±1.88‰)明显高于对照组(1.19‰±1.68‰),差异有统计学意义(P＜0.01);＞35岁年龄组的接苯工人微核发生率(3.00‰±2.76‰)明显高于≤35岁年龄组(2.02‰±1.71‰),差异有统计学意义(P＜0.05).未发现XRCCI基因多态性与微核率有关.与AAMAAA野生型比较,携带AAA/BAA、AAB/AAB、ABA/ABA及ABB/ABB双体型的接苯工人微核率明显升高,差异有统计学意义(P＜0.05).结论 苯接触能致作业工人染色体损伤.年龄及XRCC1基因双体型与苯致染色体损伤有关.     

苯接触的生物监测指标初步评估

目的：探索可客观反映职业性苯危害的灵敏指标。方法：测定苯作业车间空气苯浓度和３３名苯作业工人及４名非苯作业工人志愿者苯接触后呼出苯浓度、血苯含量及尿酚排出量，并进行相关性分析。结果：空气苯浓度（４．５～３４８ｍｇ／ｍ３）与血苯含量呈明显正相关（Ｐ＜０．０５）；血苯含量与尿酚排出量呈非常显著正相关（Ｐ＜０．０１）。结论：在低浓度苯接触时，血苯是一个与毒性相关联的特异性敏感苯吸收指标；尿酚排出量可用作高浓度苯接触工人的生物监测指标。     

甲醛对暴露工人外周血淋巴细胞的遗传损伤作用

目的评价甲醛对暴露工人外周血淋巴细胞染色体和DNA损伤水平。方法选择65名甲醛暴露工人和非甲醛暴露工人70名为研究对象，采用甲基纤维素法和单细胞凝胶电泳法，分析其外周血淋巴细胞微核发生率和DNA断裂损伤。结果暴露组工人外周血淋巴细胞微核发生率、DNA断裂损伤的细胞数，与对照组比较，差异有统计学意义（P〈0．05），并有随工龄、暴露浓度增加而增高的趋势。但甲醛浓度为0．5mg／m^3～3．11mg／m^3时，DNA断裂损伤细胞与对照组比较，差异无统计学意义（P〉0．05）。结论甲醛暴露可导致工人外周血淋巴细胞染色体和DNA断裂损伤明显增高，DNA断裂可望成为暴露人群的早期效应标志物和致癌机制之一。     

接触氯乙烯对淋巴细胞DNA损伤及微核率的研究

目的　探索低浓度氯乙烯对外周血淋巴细胞ＤＮＡ 损伤效应。方法　以呼吸带氯乙烯平均浓度低于和高于国家最高容许浓度的作业工人为低浓度组（８５ 例） 和高浓度组（７５ 例） , 不接触氯乙烯的１００ 名健康工人为对照组, 应用单细胞微量凝胶电泳技术和微核试验测定淋巴细胞ＤＮＡ 的损伤程度。结果　高、低浓度组工人淋巴细胞ＤＮＡ 平均迁移距离分别为 （４８－７ ±８－６）μｍ 和（３４－８ ±５－９） μｍ ; 微核率分别为８－８２ ‰和３－１２ ‰, 与对照组相比及高低浓度组之间相比差异有非常显著意义 （ Ｐ＜ ０－０１） 。结论　接触低浓度氯乙烯可引起淋巴细胞ＤＮＡ 损伤, 单细胞微量凝胶电泳技术可作为检测低浓度ＶＣ 职业危害的早期客观指标。     

职业性镉接触工人尿镉含量的影响因素

目的分析镉接触工人的尿镉含量的影响因素。方法选取无锡某电池厂的镉接触工人437名为接触组,另选取782名未接触镉的工人作为对照组,分析2组人群的尿镉含量水平,同时对此镍镉电池厂进行劳动卫生学调查。结果工作场所中镉及其化合物的短时间接触浓度范围为0．002～3．058mg／m3,超标率为87．5％。接触组尿镉含量（中位数1．4300μmol／mol肌酐）明显高于对照组（中位数0．7300μmol／mol肌酐）,高浓度接触组的尿镉含量（中位数1．7500μmol／mol肌酐）明显高于低浓度接触组（中位数1．2450μmol／mol肌酐）,高浓度接触组的尿镉异常率（6．40％）也明显高于低浓度接触组（2．14％）。对照组和接触组中女性尿镉含量明显高于男性;多元线性回归分析结果显示,车间空气中镉暴露水平、工龄和年龄与尿镉含量的相关系数依次为0．851、0．630和0．038。结论工作场所中镉及其化合物浓度超标、工龄的增加是尿镉含量升高的主要因素,降低工作场所空气中镉及其化合物的浓度至职业接触限值以下和减少接触时间是预防慢性镉中毒的关键。     

职业性砷暴露工人尿有机砷和8-羟基脱氧鸟苷水平的相关性

目的评价云南省某砒霜厂工人体内砷的代谢转化与DNA氧化损伤关系。方法选择云南省某砒霜厂一线工人37例（高暴露组）、管理和后勤人员16例（低暴露组）和当地近期无毒物接触史人员28例（对照组）为研究对象,检测尿中有机砷和8-羟基脱氧鸟苷水平,评价砷的代谢转化和DNA氧化损伤相关性。结果高、低暴露组男性尿有机砷分别为（0、48±0．37）mg／L、（0．08±0．05）mg／L,高、低暴露组女性尿有机砷分别为0．11mg／L、（0．30±0．24）mg／L,对照组均低于检出值下限（0．02mg／L）;高、低暴露组和对照组男性尿8-羟基脱氧鸟苷分别为（18．07±11．68）μmol／mol肌酐、（11．79±8．25）μmol／mol肌酐和（10．07±3．04）μmol／mol肌酐,高暴露组高于对照组（P〈0．05）;高、低暴露组和对照组女性尿8-羟基脱氧鸟苷浓度分别为84．35μmol／mol肌酐、（21．27±5．89）μmol／mol肌酐和（14．43±2．58）μmol／mol肌酐,暴露组女性尿8-羟基脱氧鸟苷浓度高于暴露组男性（P〈0．05）。尿中8-羟基脱氧鸟苷浓度随尿中有机砷浓度升高有上升趋势（rs=0．279,P=0．019）。结论砷职业暴露人群存在明显的DNA氧化损伤,对女性损伤更为明显,砷的代谢转化差异可能起关键作用。     

职业性镍接触工人DNA链断裂的研究

[目的]观察不锈钢冶炼职业性镍接触对工人淋巴细胞DNA损伤的影响。[方法]对某不锈钢冶炼厂相关作业环境进行监测,根据作业工种的不同,选取该厂镍接触的炼钢工（60名）、钢渣处理工（65名）及轧钢工（40名）,共165名男性工人为接触组,同时选取该企业67名水处理工为对照组,通过问卷调查收集研究对象的一般情况、职业暴露、吸烟和饮酒情况等,应用彗星试验检测工人外周血淋巴细胞的DNA损伤。[结果]炼钢工的尾惯量为（23．33±7．10）％,钢渣处理工为（22．87±10．67）％;轧钢工为（21．67±9．32）％,3组均高于对照组（10．53±5．08）％（P〈0．01）;炼钢工的尾长为（1．20±0．21）μm,钢渣处理工为（1．18土0．22）μm,轧钢工为（1．14±0．24）μm,3组也均高于对照组（0．91±0．19）μm（P〈0．01）;炼钢工、钢渣处理工和的轧钢工Olive尾矩（olive tail moment,OTM）分别为0．495±0．055、0．455±0．045和0．429±0．069,均高于对照组（0．103±0．054）（P〈0．01）。各工龄组之间OTM差异均有统计学意义（P〈0．01）;吸烟与非吸烟组之间比较,OTM值差异也有统计学意义（P〈0．05）。经相关分析表明：OTM与尿镍浓度呈正相关（r=0．576,P〈0．01）。[结论]淋巴细胞DNA损伤可能是镍职业接触工人的早期损害之一。     

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.