稳定性过氧化氢的急性毒性及刺激性试验观察

[目的]了解过氧化氢使用的安全性。[方法]按照卫生部《消毒技术规范》的检验及评价方法进行毒理学试验。[结果]稳定性过氧化氢对小白鼠急性经口LD50（♂）=2710mg／kg，LD50（♀）=2330mg／kg，属低毒；其含2．5％过氧化氢溶液对小白鼠急性经口LD50〉5000mg／kg及对皮肤刺激属无刺激性；稳定性过氧化氢对小鼠骨髓嗜多染红细胞无致微核作用。[结论]含量为2．5％的过氧化氢溶液安全可靠，可应用于杀菌消毒。     

漂白粉消毒剂的毒性测试

目的 了解漂白粉使用的安全性.方法 按卫生部《消毒技术规范》的检验及评价方法进行毒理学试验.结果 漂白粉对小鼠急性经口LD50为2 710 mg/kg,属低毒;最高应用液浓度5倍的漂白粉溶液对小鼠急性经口LD50＞5 000mg/kg;属无皮肤刺激性;对小鼠骨髓嗜多染红细胞无致微核作用.结论 漂白粉属低毒,配成溶液按最高应用浓度使用无安全问题,可广泛用于卫生消毒领域.     

二元包装过氧乙酸的相关性能试验观察

[目的]二元包装过氧乙酸是由A液(冰醋酸、硫酸)与B液(过氧化氢)按一定比例混合后反应生成过氧乙酸,观察其储存稳定性、杀菌效果和安全性等相关性能。[方法]采用理化分析方法、悬液定量杀菌试验和动物毒性试验进行了检测。[结果]该产品过氧乙酸含量为170.8g/L,于54℃恒温放置14d,其含量下降率为4.6%。以50mg/L过氧乙酸溶液对悬液内大肠杆菌作用3min,对金黄色葡萄球菌和铜绿假单胞菌作用5min,杀灭对数值均﹥5.00,以含200mg/L过氧乙酸水溶液对悬液内的白色念珠菌作用5min,杀灭对数值﹥4.00,以含750mg/L过氧乙酸水溶液对悬液内的枯草杆菌黑色变种芽孢作用10min,杀灭对数值﹥5.00。该消毒剂原液对小鼠急性经口毒性LD50值为1360.5mg/kg.BW,最高应用浓度5倍溶液的LD50值大于5000mg/kg.BW。[结论]本二元包装过氧乙酸消毒剂的稳定性好,对细菌繁殖体、真菌和细菌芽孢的杀菌效果好,动物试验原液属低毒物质、最高应用浓度5倍溶液属实际无毒。     

三氯乙醛的毒性和致突变研究

【目的】了解三氯乙醛的毒性和致突变作用。[方法]对三氯乙醛进行急性毒性试验、致突变试验、单细胞凝胶电泳试验。【结果】雄性大鼠急性经口LD50为1000mg／kg，雌性大鼠为681mg／kg。雄性大鼠急性经皮LD50为1470mg／kg，雌性大鼠为1210mg／kg。对皮肤具中等刺激性，对眼具中度至重度刺激性。Ames试验1mg／皿为阳性。小鼠骨髓细胞身长核试验160mg／kg时为阳性。小鼠与人淋巴细胞单细胞凝胶电泳试验为阳性。【结论】三氯乙醛属低毒级化学药物，致突变试验阳性。     

市售防蛀剂(含对二氯苯)急性毒性的实验研究

目的 研究市售含对二氯苯防蛀剂的急性毒性。方法 急性经口毒性选大鼠和小鼠各60只，随机分成6组，每组10只，雌雄各半，按霍恩氏(Horn)法，大鼠以0、2100、2625、3281、4101、5126mg／kg，小鼠以0、2315、3241、4537、6352、8893mg／kg防蛀片一次性灌胃。急性吸入毒性选用60只大鼠，随机分为6组，每组10只，雌雄各半，以0、3006、4510、6765、10147、15220mg／m^3防蛀片吸入2h。急性皮肤刺激实验选用白色豚鼠4只，雌雄各半，以0.5g／只涂皮4h。结果 大鼠急性经口LD50为3181.10mg／kg，小鼠急性经口LD50为3843．66mg／kg，大鼠急性吸入毒性LD50为8858mg／m^3。急性皮肤刺激实验结果属无刺激反应。结论 根据《农药登记毒理学试验方法》判定标准，3种试验结果分别属低毒级和无刺激性，但对动物中枢神经系统有抑制作用。     

二氯异氰尿酸钠复合泡腾片的研究

[目的]以二氯异氰尿酸钠为主要成分做成复合泡腾片，改善其原有的氯味高、稳定性差、毒性大等缺点。[方法]选择合适配方，制备消毒片，并进行理化、消毒效果、毒理测定。[结果]0．5g重的片剂3．04min即可完全溶解于水，密闭容器内一年有效率降低不大于0．35％，且氯味大大降低。当有效氯为100mg／L时，对细菌繁殖体作用5min，杀灭率100％；有效氯为2000mg／L，对细菌芽孢作用10min可达到消毒效果；当菌悬液中加2％蛋白胨时，对细菌芽孢需2000mg／L有效氯作用30min达到消毒效果；有效氯为1000mg／L对HBsAg作用15min可达到灭活效果。该消毒片剂急性毒理实验结果表明：LD50为4735mg／kg，属低毒类物质。[结论]二氯异氰尿酸钠复合泡腾片具有速溶、高效、稳定、微氯味、低毒等特点。     

某喷雾消毒剂杀菌性能的试验观察

[目的]观察以十二烷基苄铵、乙醇为主要杀菌成分的一种喷雾消毒剂的杀菌效果。[方法]按卫生部《消毒技术规范））2002年版要求，进行实验室杀菌效果、稳定性、金属腐蚀性及毒性进行试验研究。[结果]该喷雾消毒剂原液对大肠杆菌、金黄色葡萄球菌作用2．5min，平均杀灭对数值均〉5．00;对龟分枝杆菌作用5min，平均杀灭对数值均〉4．00；对白色葡萄球菌作用30min，平均杀灭率为99．94％。对物体表面喷雾消毒作用10min，对自然菌的平均杀灭对数值为2．14。放置54℃、RH≥75％环境中14d，十二烷基苄铵含量下降率为0．459％；对碳钢为轻度腐蚀，对不锈钢、铜、铝均基本无腐蚀。毒性试验表明，雌、雄小鼠急性经口毒性试验LD50〉5000mg／kg（体重）；急性吸入毒性试验LC50〉10000mg／kg（体重）；对白兔急性眼刺激试验属无刺激性；对小鼠骨髓嗜多染红细胞无致微核作用。[结论]该喷雾消毒剂为复方消毒剂，主要成分十二烷基苄铵、乙醇，具有较好杀菌效果。使用方便、易溶于水。对金属基本无腐蚀，属实际无毒，性能稳定，无刺激性物质。     

溴氰菊酯原药的毒性研究

目的 :研究国产溴氰菊酯原药使用的安全性。方法 :按GB1 5 6 70 - 1 995《农药登记毒理学试验方法》进行二阶段毒性测试。结果 :溴氰菊酯原药对雌雄小鼠急性经口LD50 分别为 2 3.31mg/kg .bw和 2 7.1mg/kg .bw ,雌雄大鼠急性经口LD50 均为 5 8.4mg/kg.bw。雌雄大鼠急性吸入LC50 分别为 794mg/m3和92 6mg/m3。雌雄大鼠急性经皮LD50 均大于 2 1 5 0mg/kg.bw。急性皮肤及眼刺激试验均属无刺激性。皮肤致敏试验、小鼠睾丸染色体试验、微核试验及Ames试验结果均为阴性。结论 :在本实验剂量下观察到溴氰菊酯原药对小鼠的毒性明显高于大鼠     

庄稼保护剂的急性毒性与致敏试验

目的了解生物农药庄稼保护剂的毒性和安全性。方法按照《农药登记毒理学试验方法》（GB15670—1995）进行毒性试验和安全性评价。结果该受试物对雌、雄大鼠急性经口LD50〉5000mg／kg，对雌、雄大鼠急性经皮LD50（4h）〉5000mg／kg，对家兔急性皮肤刺激反应均值积分为0，对家兔眼平均刺激指数为0；对豚鼠致敏试验，致敏率为0％。结论庄稼保护剂急性经口、经皮均属微毒性，对家兔急性皮肤刺激和眼刺激试验均为无刺激性；致敏试验，该受试物属Ⅰ级弱致敏物。     

CT5—4化学助排剂急性毒性研究

目的探讨CT5—4助排剂的急性经口、皮肤刺激和眼刺激毒性作用。方法按照《化学品毒性鉴定技术规范》（2005）进行小鼠经口急性毒性试验、大耳白兔急性皮肤刺激性试验和急性眼刺激性试验。结果小鼠经口LD50〉10000mg／kg．bw，皮肤刺激试验总积分均值为零，急性眼刺激性试验总积分平均值为4．67。结论毒性评价该化学物属低毒物，对皮肤无刺激性；对眼刺激性试验属轻度刺激性。     

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.     

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.     

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.     

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.