石家庄市居室内γ辐射及氡所致居民受照剂量的调查

目的 通过对石家庄市不同地区、不同建筑材料、不同建筑年代、不同装修材料等居室内γ辐射和氡浓度水平及其影响因素的调查分析,估算所致居民受照剂量.方法 居室内γ辐射水平采用FD-3013B型智能化γ辐射仪,氡浓度采用固体核径迹法测量累积剂量.结果 石家庄市居室内γ辐射水平均值为[0.155 ±0.023(0.107 ～0.20)] μSv/h,氡浓度平均值为[31.8±16.5(9.3 ～ 111.0)] Bq/m3,最高值均为市区、高层、瓷砖装修居室.二者所致居民剂量为1.60 mSv/a.结论 石家庄市居室内γ辐射及氡所致居民受照剂量属正常天然本底辐射水平;建筑材料是影响居室内γ辐射水平及氡浓度的主要因素,选择恰当的材料进行建筑、装修可以降低居民受照剂量,减低其对人类健康的影响.     

武汉市居室内放射性水平调查及控制

目的 了解武汉市居室内γ辐射水平和氡浓度,为控制室内放射性污染提出预防措施。方法 依据我国现行有关建材的放射性和氡的标准。结果 居室内γ辐射水平范围为(11.32±4.21)~(15.12±3.92)×10^-8Gy/h,氡浓度范围为(19.24±5.83)~(34.47±5.74)Bq/m³。结论 居室内墙体材料以废渣砖结构的γ辐射水平和氡浓度最高,γ辐射水平和氡浓度在不同建筑材料、不同季节、不同楼层有明显差别。     

煤矿氡浓度和γ射线辐射水平研究

目的调查不同种类煤矿作业场所空气中氡浓度和γ射线辐射水平。方法分别选取褐煤矿、有烟煤矿和无烟煤矿各一个,用ZYW-850型测氡仪和FD-71型闪烁辐射仪测量各矿井下采煤面、掘进面、回风巷、主巷道以及地面室内、外空气中的氡浓度和γ射线辐射水平。每个作业点测3个平行样,用算数平均数±标准差来计算各作业面氡浓度和γ射线辐射量,并与全国地面室内、外及矿区地面室内、外辐射水平相比较。结果检测的3个煤矿井下氡浓度均值为31.5±16.9 Bq·m~(-3)(N=261),波动范围为4.9~46.3 Bq·m~(-3),低于全国室内氡浓度平均水平(44.1 Bq·m~(-3));三煤矿井下γ射线空气吸收率均值8.8±5.7×10~(-8)Gy·h~(-1)(N=264),波动范围为2.9~12.3×10~(-8)Gy·h~(-1),低于我国天然γ射线辐射室内空气吸收剂量率(均值为11.95±1.7×10~(-8)Gy·h~(-1),波动范围为1.4~54.2×10~(-8)Gy·h~(-1))水平。煤矿井下氡浓度略高于矿区地面室内水平(15.1±3.5 Bq·m~(-3));井下γ射线辐射水平略低于矿区地面室内水平(13.6±3.4×10~(-8)Gy·h~(-1)),但均无显著性差异;各煤矿井下氡浓度浓度和γ射线辐射水平之间均无显著差异。结论煤矿井下空气中氡浓度和γ射线辐射水平未见显著升高。     

浙江省居室内氡浓度和γ辐射水平的初步调查

目的 初步了解浙江省居室内的氡浓度和γ辐射水平及其分布特性,估算这两类辐射所致居民的受照剂量。方法 采用固体核径迹方法和热释光剂量方法测量氡浓度和γ辐射水平;根据地级市行政区域划分,随机抽取共490个卧室或客厅开展3个月以上的累积测量;在其中75个房间开展6个月以上测量以观察两类辐射水平的季节性变化;在开展调查过程中记录建筑物的结构、建筑年代、通风情况和楼层等信息。结果 全省居室内氡浓度和γ辐射水平均值为29.3 Bq·m^-3和105.8 nSv·h^-1,所致公众的平均年有效剂量分别为0.77和0.74 mSv;新建居室内的氡浓度较高,别墅内氡浓度明显高于其他类型的建筑物,居室内氡浓度水平随通风时间减少而升高;室内氡浓度和γ辐射水平没有明显的相关性,且随季节变化也不明显。结论 当前浙江省居室内的平均氡浓度和γ辐射水平虽然不高,但室内氡浓度已有增高的趋势,值得关注与控制。     

中山市居民住宅室内γ辐射水平与氡浓度调查

目的调查中山市居民住宅室内γ辐射水平与氡浓度,进一步做好防氡降氡和防辐射措施。方法选取客厅与卧室各一个测点,γ辐射用上海电子仪器厂生产的FD-3013A型辐射仪,在近地5cm与离地1m处现场直接测量,三次读数,取均值。氡浓度用活性炭法采样现场暴露约5d,在8192道高纯锗(HPGe)γ谱仪检测。结果本次调查,中山市城区及乡镇13户住宅均未超过国家标准限值,但高于珠海市及广州市相应水平。结论应严格控制居室内γ辐射与氡浓度水平,确保辐射环境安全和居民健康。     

2009年上海市地铁车站放射性水平

[目的]了解上海市地铁车站空气氡浓度和环境γ辐射水平与变化趋势。[方法]于2009年8月至12月,在上海市已开通并在地下运行的地铁线路(1、2、4、6、8和9号线)共98个站点中随机抽取73个地铁站点,进行环境放射性水平(包括空气氡浓度和环境地表γ辐射剂量率)检测。瞬时氡浓度检测采用AB-4连续型氡测量仪,环境地表γ辐射剂量率检测采用FD-3013H智能化X/γ辐射仪。[结果]上海市6条地铁线路各站点空气氡浓度的均值为9.9Bq/m3,范围为1.2～28.4Bq/m3,明显低于国家标准规定限值。此外,各站点的环境地表γ辐射剂量率均值为(0.14±0.02)μSv/h,范围为0.07～0.24μSv/h,在天然本底辐射水平波动范围内。[结论]上海市投入运营的地铁线路各站点放射性水平属天然本底辐射水平,空气氡浓度明显低于国家标准规定限值。     

居室中放射性污染调查与辐射剂量估算

目的 探讨不同类型房屋中放射性污染水平。方法 于2003年仡太原市某社区内监测了23间不同类型房屋的室内、外氡浓度及氡子体潜能γ剂量率，以及地面和墙壁表面氡析出率。同时还测定了室内自来水和煤制气中氡浓度，地下室、平房、楼房居室中来源于土壤和建材、室外空气、水、煤制气的放射性水平。最后估算了室内、外氡暴露的年有效剂量当量。结果 室内氡浓度、氡子体潜能γ剂量率均高于室外。地面氧析出率高于墙壁。自来水和煤制气中氡浓度均值分别为4.39～7．36Bq／m^3和11．55～51．07Bq/m^3。室内放射性污染主要来源于土壤和建材中的氡析出，其次是室外宅气中的氡及γ辐射，室内用水和煤气中氡及γ辐射的贡献很小。个体暴露于室内、外氡的年总剂量当量为1．94mSv。结论本次调查的所有膳室均符合我国《：室内空气质量卫生规范》的要求。调查结果为进一步研究居住环境中放射性污染奠定了基础。     

唐山市某高校办公楼室内放射性水平与照射剂量估算

[目的]了解唐山市某高校办公大楼室内γ射线的剂量率、氡浓度及其影响因素,并估算人均年照射剂量.[方法]选择唐山市某高校办公大楼每层朝南和朝北方向的房间各1～2个,对室内地面和墙体的γ射线水平和空气中氡浓度进行测量.[结果]该办公楼地面和墙体的γ射线平均剂量率分别为(0.317±0.452) μGy/h和(0.192±0.263) μGy/h,室内氡浓度的平均值为9.43 Bq/m3.室内地面γ射线剂量率在不同地面装修材料之间差异具有统计学意义(P＜0.01),大理石地面的γ射线剂量率最高,其次为瓷砖地面,水泥地面最低.所估算的人均年照射剂量为1.72mSv·a-1.[结论]该办公大楼的放射性水平在安全范围内;地面铺设大理石增加室内γ射线水平.     

南京市某高校居室氡浓度与照射剂量估算

目的了解南京市区原野和道路的天然放射性水平、居室内氡浓度及其影响因素,为学校环境卫生标准的制订提供依据。方法对南京某高校校园的地面、道路的γ剂量率进行测量,并选取部分居室进行氡浓度和γ剂量率测量。结果校园内地面、道路的γ剂量率为70～140nGy·h-1,居室内氡浓度的变化范围为9.6～363.6Bq·m-3,所致的人均年照射剂量为2.679mSv。结论校园属于低天然放射性水平区域;室内氡浓度主要取决于通风条件,不同的建筑装修材料、楼层、气候条件等因素对氡的浓度有影响;在低放射性本底条件下,使用放射性核素较高的建筑材料、通风不畅等会导致室内氡浓度超标。     

德保铝矿区放射性水平与地质因素研究

目的 解铝矿区的土壤、室内外氡及γ辐射剂量率水平及其影响因素,为验证氡地质潜势规律提供依据。方法 采用改进型ATD累积氡探测器、专业测氡仪和FH40G环境γ剂量率仪对铝矿区及周围环境氡浓度和γ剂量率进行了测量。结果 铝矿工作区室外和室内γ照射量率均值分别是57.4和80.2 nGyh^-1;正在建设的工地为136nGyh^-1,明显高于已建好的工作区。厂区和工地土壤氡浓度分别为8864和29191 Bqm^-3,工地为厂区的3.3倍,有2点超过30 000 Bqm^-3。对照组德保县城土壤氡浓度有2点超过30 000 Bqm^-3,占抽样总数的18.2%。矿区室外氡浓度最高点为41.6 Bqm^-3,是我国室外典型值的2.97倍;室内氡浓度最高点为52.2 Bqm^-3。发现德保县城室内氡浓度均值为55.9 Bqm^-3(25.1~136 Bqm^-3,n=25),为我国典型值的1.3倍。结论 铝矿新开发工地γ剂量率和土壤氡浓度偏高,导致附近室外氡浓度有所增高。其他工作区和生活区天然辐射水平在正常本底范围。德保县城约有13.9%底层房屋中的氡浓度超过WHO(100 Bqm^-3)推荐值,氡潜势区土壤氡对室内的贡献值得关注。     

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.