重庆市及三峡库区水体微囊藻毒素污染研究

目的 了解重庆市供水系统和三峡库区水体微囊藻毒素LR（MC-LR）污染状况及其进行研究。方法于2004年5、8月先后采集重庆市主城区5个自来水处理厂源水和出厂水共10个水样以及库区干流、支流共7个断面的水样，分别进行水样和膜样的预处理，运用高效液相色谱法（HPLC）结合二极管阵列式检测器检测重庆市供水系统、三峡库区水体中微囊藻毒素的浓度。结果（1）重庆市5个自来水处理厂源水和出厂水的MC-LR检测中，化机水厂采样点的源水膜样中检出了MC-LR，浓度为0．11μg/L；其余样本均未检出MC-LR。（2）在三峡库区水域所布设的7个采样点中，有6个采样点的样本检出MC-LR，其浓度范围0．07～0．57μg／L。其中MC-LR水样检出率为86％，浓度范围0．07～0．44μg／L；MC-LR膜样检出率为43％，浓度范围0．12～0．13μg／L。结论本次检测所有检测样本MC-LR浓度均未超过WHO推荐的1μg/L安全限值。（1）重庆市主城区供水系统出厂水未检出MC-LR，饮用水较为安全。（2）在藻类高发季节，三峡库区局部水域中已能够检测出囊藻毒素，但其污染程度较低，尚未超出安全限值。     

淀山湖富营养状态调查和湖区微囊藻毒素污染现况研究

目的了解淀山湖区水质富营养状态及微囊藻毒素-LR（MC-LR）污染情况及综合整治后的效果。方法于2008年和2009年6—9月间,对淀山湖区东、南、西、北和中心5个监测点水样进行连续监测,监测指标包括总磷（TP）、总氮（TN）、浊度、pH值、耗氧量（COD）和微囊藻毒素-LR（MC-LR）。结果淀山湖湖水的pH值为7．94,呈现弱碱性,浊度20．92度、耗氧量为5．28mg／L。淀山湖水中TP浓度、TN浓度,分别在0．06—0．31μg／mL和0．2～6．3μg／mL之间波动,均超过GB3838—2006《地表水环境质量标准》中Ⅲ类标准,TN／TP的范围在0～54．4之间,水中MC—LR浓度为0．0085μg／L。结论淀山湖区水体呈一定的富营养化,且存在MC—LR污染,经近年环湖综合环境治理后有所改善。     

福建水华微囊藻毒素主要亚型及其亚慢性肝毒性

目的鉴定福建省某水库水华微囊藻毒素的主要亚型，研究该毒素对大鼠的亚慢性肝毒性。方法采集微囊藻水华，固相萃取法提取微囊藻毒素，以微囊藻毒素LR和RR纯毒素为标准，高效液相色谱法测定其亚型；SD大鼠0．42μg／（ks bw）MC-LR亚慢性染毒35d，观察血清酶学和组织病理学改变。结果该微囊藻水华检测出MC-LR，未检测出MC-RR；用藻细胞裂解液[相当于0．42μg／（ksbw））MC-LR]亚慢性染毒大鼠，血清SOD活性显著降低，SDH水平显著升高，肝脏系数显著增大，肝组织出现炎症样变化。结论福建某水库水华微囊藻毒素的主要亚型为MC-LR；亚慢性接触0．42μg／（ks bw）MC-LR的微囊藻毒素可引起肝损伤。     

绍兴三大水域富营养化状态与微囊藻毒素污染状况研究

目的了解绍兴市三大水域富营养化程度及微囊藻毒素(microcystin,MC)的污染水平。方法 2016年9月-2017年9月对绍兴萧绍河网、曹娥江、浦阳江三大流域设置15个点进行水样采集,共采集水样135份,采用超高效液相色谱-串联质谱法对微囊藻毒素(MC-LR)进行检测,同时检测总氮、总磷、高锰酸盐消耗量、氨氮、p H值、溶解氧、叶绿素a、透明度共8个环境因子指标进行综合分析。结果 135份水样中,MC-LR的检出率为16. 3%,超标率为3. 70%,三大水域均有检出,检出浓度在0μg/L～4. 28μg/L,所有阳性水样均集中在第三季度。三大水域的营养状况为中营养化到轻度富营养化水平。多元逐步回归分析显示MC-LR含量与叶绿素a和耗氧量值有相关性。结论绍兴市三大水域呈一定的富营养化,且第三季度存在微囊藻毒素的污染。     

桐庐县生活饮用水中微囊藻毒素调查

桐庐县生活饮用水主要取自富春江，富春江是浙江省最大的河流钱塘江的干流，但随着经济的快速发展，生产和生活中排入水体的污染物不断增加，特别是含氮、磷化合物的大量排放，加速了水体的富营养化进程，一些地区藻类水华频发已成为全球广泛关注的环境问题。2004年7、8月间，我县富春江大坝段面发现藻类大量繁殖，水质呈绿色，色度〉50度，耗氧量35．5mg／L，水源水中检出微囊藻毒素MC—LR0．00096mg／L，出厂水中检出0．00093mg／L，已接近《生活饮用水卫生规范-（2001）》规定的微囊藻毒素界限值（0．001mg／L）。     

水中微囊藻毒素的氧化水解产物2-甲基-3-甲氧基-4-苯基丁酸的气相色谱-质谱检测研究

[目的]采用衍生化建立一个便捷和高效的水中微囊藻毒素（MC）氧化产物2-甲基-3-甲氧基4苯基丁酸（MMPB）气相色谱-质谱仪联用（GC-MS）的检测方法。[方法]高锰酸钾氧化水样,正己烷萃取,浓缩,六氟异丙醇-二乙胺N,N-二异丙基碳酰二亚胺（HFIP．DIC）衍生化,GC-MS检测,内标法定量。[结果]通过对水样氧化水解和MMPB衍生化条件的优化,以GC-MS检测MMPB的方法检测限（MDL）为0．101gg／L（浓度均以总MC计）,线性范围为0．2～10．0μg／L,具有良好的准确度（80％-120％）、精密度（RSD〈15％）和重复性（RSD〈15％）,样品监测浓度水平为〈0．101～3．090μg／L。[结论]本方法对水中MC总量的分析提供了快速、简便、可靠的方法,能用于对日常水质中MC总量的监测分析研究。     

太原市大型水库微囊藻毒素-LR污染调查

目的了解太原市汾河一库和汾河二库微囊藻毒素-LR(MC-LR)污染状况,为制订防治微囊藻毒素-LR 污染的政策提供参考依据。方法分别于2005年5月(枯水期)、10月(平水期),在汾河一库和汾河二库的入口、中心、出口处采集水面下0.5 m 处水样5 L。采用高效液相色谱法(HPLC)检测水样中的微囊藻毒素-LR 含量。结果枯水期汾河一库水样中微囊藻毒素 LR 的平均含量为0.875 μg/L,约为平水期(0.283 μg/L)的3倍;枯水期汾河二库水样中微囊藻毒素-LR 的平均含量为0.815μg/L,约为平水期(0.048μg/L)的17倍,且均呈入口>中心>出口的趋势。枯水期汾河一库和汾河二库入口处水样中微囊藻毒素-LR含量均超过《生活饮用水卫生规范》(2001)中的限值(1μg/L)。结论汾河一库和汾河二库都存在 MC-LR 污染,且以枯水期较为严重。     

高效液相色谱-串联质谱法同时测定水产品中7种微囊藻毒素

[目的]建立用高效液相色谱一串联质谱法同时测定水产品中7种微囊藻毒素（microcystin,MC）的测定方法。[方法]样品经Tris．HCl（pH=7）缓冲液提取、HLB固相萃取柱（OasisHLB）净化、C18柱分离、电喷雾电离质谱检测、内标法定量。[结果]通过有效的提取和净化,能同时完成水产品中7种微囊藻毒素MC—LR、MC—RR、MC-YR、MC-LA、MC—LW、MC—LY和MC．LF的测定,4种不同水产品基质中10μg／kg、40tc／kg加标回收率为51％～112％和60％．117％,相对标准偏差分别为1．7％～12．7％和0．9％～8．0％（n=6）;检出限为0．20—0．40μg／kg。[结论]本研究建立的液相色谱一串联质谱同时测定水产品中7种微囊藻毒素的测定方法是测定水产品中微囊藻毒素残留量快速、有效、实用的方法,能为水产品中微囊藻毒素的监测提供有力的技术保障。     

微囊藻毒素-LR诱导肝细胞氧化应激

目的 研究微囊藻毒素-LR在不引细胞毒性的剂量（3～30μg／L）时对肝细胞的氧化应激。方法以HL-7702细胞株为模型，检测细胞内的酶系统损伤情况。结果细胞内过氧化氢酶（CAT）、谷胱甘肽（GSH）和超氧化物歧化酶（SOD）随着毒素剂量的升高和作用时间的延长而降低，而乳酸脱氢酶（LDH）渗出率及丙二醛（MDA）含量同对照组相比差异无统计学意义。结论微囊藻毒素-LR在非细胞毒性的剂量下可引起肝细胞的氧化应激，但尚不足以导致脂质过氧化。     

福建省部分食品中N—亚硝胺含量调查结果分析

应用气相色谱-热能分析仪检测啤酒、鱼露、鱼、肉制品中N-亚硝胺，啤酒中检出N-业硝基二甲胺含量范围0．9～9．5μg／L；鱼露中检出N-亚硝基二甲胺含量范围0。1~0．43μg／L；肉制品100％检出N-亚硝胺，其中N-亚硝基二甲胺（NDMA）0.08～2.6μg／kg。N-亚硝基二乙胺（NDEA）0．13～1．7μg／kg．N--亚硝基二丙胺（NDPA）0.18～8．78μg／kg，N-亚硝基吡咯（NPYR）0．21～27．34μg／kg。咸鱼和风干海产品100％检出亚硝基二甲胺、含量在0.12～0.18μg／kg。1材料与方法：1．1材料：啤酒样品采自福建省各啤酒厂．鱼露采自福州、长…     

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.