蔬菜中残留农药的调查及消除效果观察

应用GC—9A气相色谱仪检测深圳市售蔬菜15种,123份样品,结果发现有78份蔬菜中含有机磷农药,阳性率为63.41％,其中菜心、芥菜、芥兰菜阳性率高达76.7～92.3％;在有机磷农药中,检出敌敌畏、甲胺磷、杀虫松、乐果、甲基对硫磷、马拉硫磷六种;其中有严禁使用的甲胺磷、甲基对硫磷剧毒农药,而且甲胺磷的含量高达8.77～24mg/kg,为了防止蔬菜中残留农药引起食物中毒的发生,试用了八种方法对蔬菜中残留农药消除效果进行了研究,结果发现菜中残留农药以自来水浸泡,流水冲洗法的消除率仅有12.7～37.6％,而应用80～90℃热水处理5分钟消除菜中有机磷农药的效果较好,随着处理时间的延长、温度增高,消除率高达95.8～99.7％。     

中山市上市蔬菜中有机磷农药残留调查

目的调查中山市上市蔬菜中有机磷农药残留的状况。方法调查的蔬菜类别分叶菜类、瓜果类和根茎类,有机磷农药范围主要是敌敌畏、甲胺磷、乙酰甲胺磷、氧化乐果、乐果、马拉硫磷、喹硫磷、甲拌磷、久效磷、对硫磷、甲基对硫磷、水胺硫磷等12种农民较常使用的农药。结果蔬菜中有机磷农药残留量超标率30.1%,检出甲胺磷的比率达18.2%。结论初步调查清楚农民使用最多的农药是甲胺磷,而且往往大多同时使用多种农药于同一蔬菜上。蔬菜中有机磷农药残留超标、超范围使用现象仍然较严重,但有逐渐下降的趋势。     

中山市秋季市售蔬菜中有机磷农药残留调查分析

目的 了解中山市秋季市售蔬菜中有机磷农药残留的状况。方法 2002年11月随机选取中山市3个市场进行蔬菜样品抽样,调查的蔬菜类别分叶菜类、瓜果类和根茎类,采用气相色谱法检测蔬菜中敌敌畏、甲胺磷、乙酰甲胺磷、氧化乐果、乐果、马拉硫磷、硅硫磷、甲拌磷、久效磷、对硫磷、甲基对硫磷、水胺硫磷12种农民较常使用的农药。结果 蔬菜中有机磷农药残留量超标率为45．6％,其中甲胺磷的检出率最高为27．8％。47份阳性样品中共检出10种农药,同时检出2种及2种以上农药的有26份,占55.3％。在3类蔬菜中均检出的农药有甲胺磷、乙酰甲胺磷和氧化乐果。结论 中山市农民使用最多的农药是甲胺磷,而且往往大多同时使用多种农药于同一蔬菜上。蔬菜中有机磷农药残留超标、超范围使用现象仍然较严重。     

不同洗涤方法对黄瓜中有机磷农药的去除效果

目的比较清水、淘米水、淡盐水和洗洁精水溶液浸洗2～15 min对黄瓜中有机磷农药甲胺磷和乐果的去除效果.方法采用超声波萃取和气相色谱-火焰光度检测法测定黄瓜中的有机磷农药残留.结果清水、淘米水、淡盐水和洗洁精水溶液浸泡2～15 min后,黄瓜中甲胺磷和乐果的平均去除率分别为66%～22.4%和67.7%～79.6%.4种洗涤方法均可降低蔬菜瓜果中有机磷农药残留量,但不可能完全避免农药残留的危害,清水浸泡2～5 min对去除黄瓜中甲胺磷和乐果残留的最高去除率接近70%.洗涤2、5、10、15min后,甲胺磷和乐果去除率变化无规律.结论清水、淘米水、淡盐水和洗洁精水溶液浸洗2～15min仍未能彻底去除黄瓜中的有机磷农药残留,随浸洗时间的延长,甲胺磷和乐果残留的去除效果无明显变化.建议采用清水浸泡2～5 min的方法清洗蔬菜瓜果.     

毛细管气相色谱法测定食品中11种有机磷农药

甲胺磷、敌敌畏、氧化乐果、久效磷、甲拌磷、乐果、甲基对硫磷、杀螟松、马拉硫磷、对硫磷、水胺硫磷是目前蔬菜中较常使用的有机磷农药 ,而且由这些农药引起的食物中毒事件时有发生。中华人民共和国国家标准中测定这些有机磷农药需要采用两根填充柱才能完成[1 ] ,不但操作繁琐、分析时间长 ,而且色谱柱对个别有机磷农药如乐果、氧化乐果等吸附性较强 ,给测定结果造成一定的误差。本文采用PE -5毛细管色谱柱一次性分析上述 11种有机磷农药 ,获得了令人满意的结果 ,回收率为 80 5 %～ 10 1 4% ,相对标准偏差 3 5 %～ 8 6%。1　实验部分1 …     

毛细管气相色谱法测定食品中11种有机磷农药

甲胺磷,敌敌畏,氧化乐果,久效磷,甲拦磷,乐果,甲基对硫磷,杀螟松,马拉硫磷,对硫磷,水胺硫磷是我省目前蔬菜中较常使用的有机磷农药,而且由这些农药引起的食物中毒事件也时有发生,国家标准检验方法中测定这些有机磷农药需采用两根填充柱才能完成,不但操作烦琐,分析时间长,而且色谱柱对个别有机磷农药如乐果,氧化乐果等吸附性较强,测定结果误差较大,本文采用PE-5毛细管色谱柱一次性分析上述11种有机磷,获得了令人满意的结果,回收率为80.5%-101.4%,相对标准偏差为3.5%-8.6%.     

竞争性受体结合试验检测农药拟雌激素样作用

【目的】应用竞争性受体结合试验检测常用六种农药的雌激素样活性。[方法]选用乐果、乙酰甲胺磷、久效磷、马拉硫磷、对硫磷和对氧磷6种有机磷农药进行大鼠子宫雌激素受体竞争性结合试验。【结果】应用多点饱和分析建立Scatchard图，采用10nmol／L^3 H-E。作单点饱和分析，结果显示这6种有机磷农药的结合率均未下降到50％。【结论】这6种有机磷农药不能与大鼠子宫雌激素受体的位点结合。     

用MCF-7细胞检测有机磷农药拟雌激素样活性

目的 观察常用有机磷农药对MCF-7细胞增殖以及对雌激素受体基因和pS2基因表达的影响。方法 选用乐果、乙酰甲胺磷、久效磷、马拉硫磷、对硫磷、对氧磷6种有机磷农药进行MCF-7人乳腺癌细胞增殖实验和转录活化实验。结果 6种有机磷农药不能诱导MCF-7人乳腺癌细胞增殖,但乐果却能使pS2基因表达上调。结论 乐果可能具有拟雌激素样活性,且引起pS2基因表达上调不通过雌激素受体介导。     

蔬菜中有机磷农药残留情况的调查

目的了解济南市市售蔬菜的有机磷农药残留状况。方法2005--2007年，于不同季节对济南市4个大型农贸市场销售的卷心菜、小白菜、菠菜、青椒、黄瓜、豆角、韭菜、花椰菜进行采样，蔬菜样品经提取、净化、浓缩后，用毛细管柱气相色谱法检测甲胺磷、对硫磷、甲基对硫磷、敌敌畏、甲拌磷、久效磷、氧化乐果、乐果、毒死蜱、马拉硫磷等有机磷农药残留情况。结果共采集蔬菜样品597件，总检出率32．66％，总超标率25．63％；韭菜中农药的检出率和超标率最高，分别为65．56％和52．22％，且存在严重的多种农药检出和超标现象；农药污染以甲胺磷最为严重，检测最高值达到114．013mg／kg，其次为氧化乐果，为11．807mg／kg；调查第二年农药使用情况比第一年有所好转；各农药的检出情况存在一定的季节差异。结论本次调查的蔬菜样品高毒性有机磷农药检出率及超标率较高，农药残留情况较严重。     

2009年苏州市蔬菜中有机磷农药残留状况监测及分析

目的:了解江苏省苏州市市售蔬菜中有机磷农药污染现状。方法:采用毛细管气相色谱法测定蔬菜中有机磷农药残留。结果:本次蔬菜检测不合格率为15.2%,其中叶菜类,根茎类,瓜果类不合格率分别占10.8%,3.1%,1.3%。共检测出甲胺磷,敌敌畏,乐果,马拉硫磷,毒死蜱,久效磷,甲拌磷7种有机磷农药。结论:我市蔬菜中有机磷农药残留依然严重,需要加大监督管理力度,保证消费者身体健康。     

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 human drama of genetics: 'hard' and 'soft' media representations of inherited breast cancer

This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.     

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.     

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.     

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.     

The risk of heat exhaustion at a deep underground metalliferous mine in relation to surface temperatures

The risk of heat exhaustion at a deep underground metalliferous mine was assessed in relation to thermal conditions prevailing on the surface. For each day of a 1-year prospective case series of heat exhaustion, surface 24-h mean wet and dry bulb temperatures were recorded. From this data, 24-h mean wet bulb globe temperatures were derived using certain assumptions. The three surface temperature variables were significantly higher on those days on which heat exhaustion occurred, compared to those days on which it did not occur (P < 0.001). The relative risk of heat exhaustion on days when the 24-h mean wet bulb globe temperature was in the range 26.0-28.0 degrees C was 4.82 (95% confidence interval 2.12-10.96). Surface temperature data could be used at this mine to warn miners about the risk of heat exhaustion.