汾河二库水体富营养化调查

[目的]了解汾河二库水体现阶段的富营养状况.[方法]通过检测水体的透明度、总氮、总磷、叶绿素-A、藻细胞密度等指标,并通过计算水质营养状态指数(TSI)对其富营养化作出综合评价.[结果]汾河二库枯水期和平水期水样透明度都低于GHZBI-1999《地表水环境质量标准》中的Ⅳ类标准;枯水期TN分量高于平水期,但均低于GB3838-2002《地表水环境质量标准》中的Ⅳ类标准;枯水期和平水期TP含量低于GB8838-2002《地表水环境质量标准》中的Ⅳ类标准;水样中叶绿素-a含量都未超过GHZBI-1999《地表水环境质量标准》中的Ⅳ类标准;TSI(SD)、TSI(TP)都大于50,TSI(chla)小于50;藻细胞总数在枯水期达到5.9×105 个/L,明显多于平水期藻细胞总数(2.5×104个/L).[结论]汾河二库尚未形成富营养化状态.     

汾河太原段枯水期水体富营养化调查

目的 了解汾河太原段水体的营养化现状.方法 选择5个监测断面:汾河水库出口、寨上水文站、胜利桥、小店桥、清徐二坝,通过检测各断面水体的水温、pH值、色度、总氮(TN)、总磷(TP)、叶绿素-a、藻细胞密度等指标,并计算水质营养状态指数(TSI)对其富营养化作出综合评价.结果 汾河水库出口及胜利桥2断面的水质TP含量(0.028,0.041mg/L)未超过地表水环境质量Ⅲ级标准(GB3838-2002)(0.2mg/L),寨上水文站、小店桥和清徐二坝3个采样断面TP含量(1.236,2.552,0.748 mg/L)以及5个采样断面的TN含量(5.017,15.177,5.262,20.842,20.484mg/L)均为劣V类.水质严重污染.各断面水中叶绿素-a含量(平均1.174ug/L)均未超过GHZBI-1999(地表水环境质量标准)中的Ⅲ类标准(10ug/L);藻细胞总数在枯水期均超过1×106个/L,汾河太原段总河段枯水期平均TSI值为57.68,呈轻度富营养化.结论 汾河太原段呈现中营养化向轻度富营养化过渡状态.     

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。     

淮河流域某县水体富营养化及水体、底泥微囊藻毒素污染状况研究

目的研究淮河流域某县不同水体中富营养化状态和藻类及微囊藻毒素的污染状况。方法分别于平水期(5月)和丰水期(8月),采集淮河流域某县S河、Y河和代表性池塘的水和底泥,国标方法测定水中总氮、总磷、叶绿素a、化学耗氧量、藻细胞密度;利用固相萃取-高效液相色谱法测定水中溶解性、藻细胞内和底泥中微囊藻毒素MC-LF/LR/LW/RR/YR。结果该县水污染严重,氮磷严重超标,多数检测指标处于Ⅲ类～劣Ⅴ类水质。干流S河以总氮污染最为严重(4.78mg/L),丰水期水质显著好于平水期(P<0.05)。内河Y河和池塘水则是丰水期水质劣于平水期,池塘水中叶绿素a浓度最高达648.4mg/m3。不同水体平水期蓝藻比例低于10%,丰水期急剧增高至40%,成为优势藻,池塘水蓝藻占44%。水中溶解性、藻细胞内、底泥中的主要微囊藻毒素为MC-RR,水中MC-RR浓度最高达17.731μg/L,底泥中MC-RR浓度最高达0.802μg/g,而多数样品中MC-LR/LF/LR/YR检出率和浓度均较低。结论该县水体处于中度和重度富营养化状态,丰水期底泥中的MC-RR含量显著高于平水期(P<0.05)。     

淀山湖不同水文时期水质变化及与水体中叶绿素a含量的关系

目的通过监测淀山湖不同水文时期水质污染指标及水体中叶绿素a含量水平,评估淀山湖水质富营养化现状并探究不同污染指标对水体藻类生长的影响。方法于2017年1—7月在淀山湖入水、出水和湖中心分别设置5个采样点,采集水样进行主要污染指标及水体中藻类叶绿素a含量的测定。结果水质浊度监测均值为6.37 NTU,pH均值为8.13,高锰酸盐指数(CODMn)均值为3.69 mg/L,达到地表水环境质量标准限定的Ⅲ类水质标准;氨氮和亚硝酸盐氮的监测均值分别为0.92和0.042 mg/L,分别符合地表水环境质量标准限定的Ⅳ和Ⅱ类水质标准;藻类叶绿素a含量的监测均值为10.52 mg/L,明显超过了地表水环境质量标准限定的Ⅴ类水质标准。枯水期和平水期的水质污染指标中除氨氮和亚硝酸盐氮的均值高于丰水期外,其他指标均优于丰水期,水质相对较好。丰水期温度、浑浊度、pH值、化学需氧量(COD)和叶绿素a高于枯水期和平水期,且与枯水期和平水期相比差异有统计学差异(P0.05);丰水期氨氮和亚硝酸盐氮水平低于枯水期和平水期,且丰水期氨氮水平与枯水期和平水期相比差异有统计学差异(P0.05)。藻类叶绿素a含量与水体温度(R=0.511,P0.01)和pH值(R=0.636,P0.01)呈正相关,和亚硝酸盐氮含量呈负相关(R=-0.666,P0.01),而浑浊度(R=0.342,P0.05)、氨氮(R=-0.351,P0.05)、CODMn(R=0.261,P0.05)与叶绿素a无统计学关联。结论淀山湖水体富营养化水平严重,丰水期水体藻类叶绿素a含量显著升高,可能与温度和pH值有关,而与水体中浑浊度、氨氮、亚硝酸盐氮及CODMn没有关联。     

广州市饮用水中双酚A及邻苯二甲酸酯的调查

目的了解广州市饮用水中双酚A、邻苯二甲酸二乙酯和邻苯二甲酸二丁酯的污染现状。方法于2014年的枯水期(1—2月)、春季平水期(3—4月)、丰水期(5—8月)和秋季平水期(9—10月),采集广州市现有7家市政水厂的水源水、出厂水及管网末梢水各28份,采用液相色谱-质谱法(LC/MS)进行双酚A(BPA)、邻苯二甲酸二乙酯(DEP)和邻苯二甲酸二丁酯(DBP)含量的测定。结果水源水、出厂水和管网末梢水全部水样的DBP含量超标,出厂水和管网末梢水全部水样的BPA和DEP含量达标,水源水中BPA和DEP均有检出;水源水丰水期BPA含量低于枯水期(P0.05)和秋季平水期(P0.01),水源水丰水期DEP含量低于秋季平水期(P0.01);出厂水和管网末梢水中BPA含量均低于水源水(P0.01),管网末梢水中DEP含量高于水源水(P0.05),出厂水和管网末梢水中DBP含量均高于水源水(P0.01)。结论广州市饮用水中DBP的含量较高,应结合不同水处理工艺采取控制措施。     

太原市引黄供水体系水体富营养化调查

目的 调查山西省太原市引黄供水体系藻类污染状况.方法 分别于2006年5月从万家寨水库、呼延水厂入厂水和出厂水、管网末梢4个环节采集水样,检测总氮(TN)、总磷(TP)、叶绿素-a(Chla)、微囊藻毒素-LR(MC-LR)含量和藻细胞总数,评价其富营养化和藻类污染状况.结果 万家寨水库总氮(3.921 mg/L),总磷含量(0.145 mg/L)均高于地面水环境质量标准III级标准(GB383-2002.TN 1.0 mg/L,TP 0.05 mg/L);叶绿索-a含量为2.389μg/L,藻细胞数达到150 × 104个/L,MC-LR含量为0.945μg/L,未超过生活饮用水质中MC-LR限值(1μg/L).呼延水厂入厂水除总磷(0.029 mg/L)低于地面水环境质量标准Ⅲ级标准外,其余各项指标与万家寨差别不明显.出厂水和管网水中的藻细胞数和MC-LR含量均比入厂水有明显减少,未检测到叶绿素-a,但管网总氮、总磷含量比出厂水增高.结果 万家寨水库呈现富营养化,有较多藻类污染.出厂水和管网水中存在较高总氮和总磷污染.     

集中式供水水源水藻类生长相关指标及变化特征分析

目的分析水源水中藻类的时间分布特征及其影响因素。方法于2011—2013年,每月采集海口市某集中式供水水源水进行水质检测及藻密度和种类的鉴定。结果三年期间,该水源水中的藻密度为5.35×106个/L,枯、丰、平水期藻密度分别为5.52×106、5.31×106、5.23×106个/L;水中的藻密度与p H、色度均呈正相关(P0.05),与总氮、总磷、硝酸盐氮、COD、浑浊度无相关性(P0.05)。结论该水源水可能存在枯水期藻类增长的潜在风险。     

郑州市某地表水源叶绿素a与相关环境因子的关系

目的 了解郑州市某地表水源营养化状况,并建立叶绿素a(Chla)的预测模型.方法 于2004年3-10月,在郑州市某人工湖选择具有代表性的2处作为采样点:1号采样点为以该人工湖为水源的某水厂调蓄池人口处,2号采样点为调蓄池以北1 000m处.每个采样点在春季、夏季、秋季各采样10、9、6次.按照<水和废水检测分析方法>对样品中叶绿素a、水温(WT)、透明度(SD)、高锰酸盐指数(CODMn)、总氮(TN)、总磷(TP)进行检测.采用综合营养状态指数法来评价该水源的营养状态,应用直线相关分析和多元回归方法探讨叶绿素a与环境因子之间的关系,并初步建立叶绿素a的预测模型.结果 该水源在春季、夏季和秋季营养状态依次为中营养状态、轻度富营养状态和中度富营养状态.ln(CChla 1)与WT、CODMn、TP呈正相关,与SD呈负相关,差异均有统计学意义(P＜0.05).叶绿素a的预测模型为ln(CChle 1)=-0.114 0.083 48 WT 6.874 TP 0.193 CODMn(R2=0.900,F=62.674,P＜0.01),应用该方程计算出的ln(CChla 1)预测值能够较好地与实测值拟合.结论 该水源已出现富营养化状态;削减TP和CODMn含量对控制叶绿素a含量具有现实意义.     

广州市海珠区某水厂水样微量元素检测及致突变初步研究

目的了解某水厂在不同时期水样的微量元素的含量和致突变性以及消毒剂、沉淀剂浓度与致突变的关系。方法采集广州市海珠区某水厂在丰水期、枯水期、平水期的水源水、待滤水、出厂水、末梢水的水样,利用电感耦合等离子体质谱仪(ICP-MS)检测水中Cr、Mn、Fe、Cu、As、Ag、Cd、Ba、Pb、Zn、Al、Se等12种微量元素含量,并进行蚕豆根尖细胞微核试验。同时对沉淀剂(硫酸铝钾)、消毒剂(次氯酸钠)进行蚕豆根尖细胞微核试验,检测其致突变作用。结果枯水期该水厂出厂水和末梢水的锰、铁、和镉均超标;枯水期水源水水样的微核率(9.33‰)高于阴性对照(2.33‰),差异有统计学意义(P<0.01)。硫酸铝钾(铝离子浓度)>11.38mg/L和消毒水(有效氯浓度)>1.25mg/L时,其微核率>10‰,且与阴性对照比较差异有统计学意义(P<0.01),其浓度均与微核率呈正相关(P<0.01)。结论该水厂枯水期水质欠佳,水源水可诱发蚕豆根尖细胞微核增多,较高浓度硫酸铝钾沉淀剂和次氯酸钠消毒剂对其有一定的致突变作用。     

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.