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1.
人发是反映机体微量元素慢性代谢较好的样品之一,微量元素含量放血液高1-2个数量级,且受机体自稳机制的影响小,无痛,易采集. 人发中微量元素的分析测试方法时有报道,ICP-AES法具有快速、简便,检测限低,精密度高,干扰少,多元素同时测定等优点,对分析人发中微量元素有明显的优越性.木文研究了用法国JY-70P等离子光量计同时测定人发中铜、锌、  相似文献   

2.
以某高校新生发样为研究样本,将生源地分为东北、西北、西南、华北、华南、华中、华东7个地域,采用电感耦合等离子发射光谱法对发样中所含铬、铜、镍、铅、锌进行测定,通过非参数检验及偏相关性检验分析不同地区发样中重金属含量与性别、身体质量指数(BMI)的关系。结果显示,所采集发样中铬、铜、镍、铅、锌的含量变化范围依次为0.22~101.84、0.36~112.24、0.70~128.75、1.39~136.13、1.12~719.50μg/g;发样中重金属浓度的地区排序为东北>华东>华北>西北>华中>西南>华南。聚类分析和主成分分析结果显示,不同地区发样中重金属的来源有所差异:东北、西北、华北地区发样中重金属可能主要来源于燃煤、工业生产过程、机动车排放,方差贡献率分别为39.47%、25.78%、22.89%;华中、华东、西南、华南地区发样中重金属可能主要来源于工业生产过程、机动车排放、冶金化工过程,贡献率分别为47.76%、27.51%、18.24%。相关性检验显示,男性发样内铬、铜、镍、铅含量高于女性。其中,偏胖或偏瘦女性存在较高的铅暴露风险;40.2%的男性发锌含量低于正常值下限,24.4%的女性发锌含量低于正常值下限,且偏瘦女性发内缺锌现象显著;男、女发铜含量高于正常值上限的比例分别为91.8%、85.6%,存在不同程度的铜暴露风险。  相似文献   

3.
环境、微量元素及人体健康之间存在着十分密切的关系.迄今为止,在人体内已经发现了60多种微量元素.人发中的微量元素含量,可以反映出人体微量元素的水平.人发样品易于采集,易于保存,代表性好.因而测定人发微量元素的工作对环境科学、诊断疾病、评定营养状况和环境污染状况等方面起着重要作用.  相似文献   

4.
本文根据绿色食品土壤质量规定要求,对甘肃河西地区五个农场申报绿色食品基地土壤中微量元素及农药进行了测定,并同本地区土壤背景值进行了对比。  相似文献   

5.
将每天TSP、SO_2两种污染物各采四次样并分别进行测定,简化为每天各采一个“日混合样”进行测定,对测定结果进行数理统计检验结果表明:测定值之间不存在显著性差异、两种方法的测值波动是由偶然因素造成的,因此,简化方法即采日混合样进行分析是一种可靠的监测方法,它适用于煤质中含硫份较低的地区。  相似文献   

6.
氢化物发生——原子吸收法测定人发中砷   总被引:5,自引:0,他引:5  
应用自制氢化物发生才电加热石英管原子吸收仪测定人发中砷。用硝酸-高氯酸进行消解,加入碘化钾溶液、抗坏血酸-硫脲混合液,消除了各种元素的干扰。方法简便快速、灵敏度高。发样砷的方法检测限为0.03mg/kg,相对标准偏差在2.5%以内。  相似文献   

7.
设计了一种简便,实用的固体进样装置,进行无焰原子吸收测定树叶中的痕量铬.建立了一种准确快速测定树叶中微量元素的方法,适合于常规环境试样分析.特证质量0.9Pg/0.0044A,回收率95-98%,变异系数5.1-5.7%.  相似文献   

8.
为了获得土壤样品中微量元素的准确含量,必须严格实验室内的质量控制,以保证分析结果的可靠性和可比性。除严格执行总课题组“实验室分析质量保证技术规定”外,根据我站仪器配备的实际情况,选择合适的分析测试方法,并对硒、铬、铅、钒、氟、镉、汞等分析方法进行了改进,考核结果全部合格。在样品测定过程中,分析测试人员用不同种类的标准土样进行自检,再辅以20%密码平行双样控制测定精密度,并测定了总站下发的室间控制样(ESS—4)。保证了实验室自始至终处于受控状态,从而保证了数据质量。  相似文献   

9.
环境空气质量不同监测方法的对比   总被引:1,自引:0,他引:1       下载免费PDF全文
在对环境空气质量的监测中,有些城市存在着人工采样实验室测定和连续自动监测系统监测并行的情况。为考察这两种方法监测结果的异同,于夏季连续20d和冬季连续15d进行了对比监测。监测项目为SO2,NO2和PM10。在对比监测中采取了质量控制措施。对人工采样实验室测定进行了综合采样器流量校正,现场空白样和全程序平行样测定;在自动监测系统中,对SO2,NO2监测仪器作零点,标点校正,PM10监测仪作K0校正。对所测得的209个日均值进行了统计分析,结果表明:SO2,PM10两方面测定结果方差相同,NO2两种方法在冬夏两季方差间均有显著性差异;夏季SO2,PM10,冬季NO2两种方法监测结果一致;冬季SO2,PM10,夏季NO2两种方法监测结果有显著性差异;样品浓度水平及天气状况对两种方法测定结果的差异亦产生较大的影响。  相似文献   

10.
硒是动物和人类必须的微量元素,某些地区水、土壤、植物中硒含量很高而导致家畜发生地方性疾病,硒含量缺乏会使人类诱发心血管疾病和癌症,已引起国内外许多科学家的特别关注。生物样品中痕量硒的荧光法测定,具有灵敏度高,选择性好,操做简便等优点,但样品的消解方法十分关键。 K.Wmiehacl等,比较研究了HNO_3-Mg(NO_3)_2及  相似文献   

11.
Leaves of the deciduous tree species, horse chestnut (Aesculus hippocastanum L.) and Turkish hazel (Corylus colurna L.) were used as accumulative biomonitors of trace metal pollution in the urban area of Belgrade. Using differential pulse anodic stripping voltametry, trace metal concentrations (Pb, Cu, Zn, Cd) were determined at the single leaf level (ten leaves per species, per month), during two successive years with markedly different atmospheric level of trace metals. Increased trace metal concentrations in the leaves of A. hippocastanum reflected elevated atmospheric trace metal pollution, whereas C. colurna L. did not respond accordingly. The contents of Pb and Zn in soil over the same period also followed this trend. Anatomical analyses, in young as well as in old leaves of both species, indicated typical foliar injuries of plants exposed to stressful air conditions. Water relations that correspond to leaf age may have contributed to the considerable trace metal accumulation in leaves.  相似文献   

12.
中子活化分析在研究成都市大气飘尘中的应用   总被引:7,自引:0,他引:7  
由于成都市特定的地理环境和逆温差效应的气候特点,成都市的大气污染在横向和纵向上几乎都不能扩散,而只能就地弥漫。本文就利用中子活化这一核分析技术,对成都市不同季节、不同地点的大气飘尘中微量元素(特别是As、Cr、Th、U等有害元素)的变化进行了初步分析。  相似文献   

13.
Cu, Cd, Zn, Pb and Se concentrations were measured in the bivalve mollusc Saccostrea glomerata(Iredale and Roughly) from two uncontaminated locations, Clyde River Estuary, Batemans Bay and Moona Moona Creek, Jervis Bay, to determine natural variability of metals associated with mass, gender, age, tissue type and site within location. Trace metals were also measured in the Clyde River Estuary over an 11 year period and in five other NSW estuaries (Hastings River, Hunter River, Georges River, Tillgerry Creek and Lake Pambula) over a 13-month period to determine temporal variability and if diploid and triploid oysters accumulate trace metals differently. There were few significant relationships between trace metal concentrations and mass and no significant differences in trace metal concentrations between female and male oysters. Younger oysters (1.3 years) had significantly higher copper concentrations and higher trace metal variability than mature oysters (3 years). Different tissues have different trace metal concentrations with muscle tissues having lower concentrations. Considerable inherent variability occurs in oyster cohorts. Analysing specific tissues did not reduce variability of trace metal concentrations. Comparison of trace metal concentrations at two sites within the Clyde Estuary showed a significant difference in zinc concentrations. Cu, Cd, Zn and Se concentrations were generally higher and less variable in triploids than diploids. Pb had a variable pattern of accumulation with no consistent elevation in diploids or triploids. Inter annual variability of trace metal concentrations was considerable and trace metal concentrations also fluctuated throughout an annual cycle with no clear seasonal trends. Measurement of trace metals at known contaminated locations showed that Saccostrea glomerata accumulates metals in response to contamination. Saccostrea glomerata meet most of the requirements to be a biomonitor of trace metal contamination as they are abundant, sessile/sedentary, easy to identify, provide sufficient tissue for analysis, and accumulate trace metals in response to contamination. However, as trace metal concentrations can vary with mass, age, estuary position, ploidy type and temporally, care must be taken to collect individual organisms of similar mass, age and ploidy type to minimise variability, and from similar consistent positions and times to allow for seasonal changes in environmental conditions. Trace metal concentration variability is higher in young animals, thus to reduce variability, older mature animals could be selected. However, with immature oysters there are no complications because of the effects of spawning i.e. sudden loss of trace metals or body mass.  相似文献   

14.
Concentrations of organochlorine pesticides (DDTs, HCHs, and chlordanes), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), perfluorinated compounds (PFCs), and 20 trace elements were determined in livers of 3- to 5-year old stranded sea otters collected from the coastal waters of California, Washington, and Alaska (USA) and from Kamchatka (Russia). Concentrations of organochlorine pesticides, PCBs, and PBDEs were high in sea otters collected from the California coast. Concentrations of DDTs were 10-fold higher in California sea otters than in otters from other locations; PCB concentrations were 5-fold higher, and PBDE concentrations were 2-fold higher, in California sea otters than in otters from other locations. Concentrations of PAHs were higher in sea otters from Prince William Sound than in sea otters from other locations. Concentrations of several trace elements were elevated in sea otters collected from California and Prince William Sound. Elevated concentrations of Mn and Zn in sea otters from California and Prince William Sound were indicative of oxidative stress-related injuries in these two populations. Concentrations of all of the target compounds, including trace elements, that were analyzed in sea otters from Kamchatka were lower than those found from the US coastal locations.  相似文献   

15.
Bioindicators are widely used in the study of trace elements inputs into the environment and great efforts have been conducted to separate atmospheric from soil borne inputs on biomass accumulation. Many monitoring studies of trace element pollution take into account the dust particles located in the plant surface plus the contents of the plant tissues. However, it is usually only the trace element content in the plant tissues that is relevant on plant health. Enrichment factor equations take into account the trace element enrichment of biomasses with respect soil or bedrocks by comparing the ratios of the trace element in question to a lithogenic element, usually Al. However, the enrichment equations currently in use are inadequate because they do not take into account the fact that Al (or whichever reference element) and the element in question may have different solubility-absorption-retention levels depending on the rock and soil types involved. This constrain will become critical when results from different sites are compared and so in this article we propose that the solubility factors of each element are taken into account in order to overcome this constrain. We analysed Sb, Co, Ni, Cr, Pb, Cd, Mn, V, Zn, Cu, As, Hg, and Al concentration in different zones of Catalonia (NE Spain) using the evergreen oak Quercus ilex and the moss Hypnum cupressiforme as target species. We compared the results obtained in rural and non industrial areas with those from the Barcelona Metropolitan Area. We observed differences in Al concentrations of soils and bedrocks at each different site, together with the differences in solubility between Al and the element in question, and a weak correlation between total soil content and water extract content through different sites for most trace elements. All these findings show the unsuitability of the current enrichment factors for calculating lithospheric and atmospheric contributions to trace element concentrations in biomass tissues. The trace element enrichment factors were calculated by subtracting the part predicted by substrate composition (deduced from water extracts from soils and bedrock) from total concentrations. Results showed that for most of the trace elements analysed, trace elements enrichment factors were higher inside the Barcelona Metropolitan Area than outside, a finding that indicates that greater atmospheric inputs occur in urban areas. The results show that the most useful and correct way of establishing a reference for lithospheric and atmospheric inputs into the plant tissues is, first, to analyse samples of the same plant species collected from a number of sites possessing similar environmental conditions (climate, vegetation type, soil type) and, second, to use this new enrichment factor obtained by subtracting from the total concentration in plant tissue the predicted contribution of soil or bedrock extracts instead of that of total soil or bedrock concentrations.  相似文献   

16.
Research on trace elements and the effects of their ingestion on human health is often seen in scientific literature. However, little research has been done on the distribution of trace elements in the environment and their impact on health. This paper examines what characteristics among participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study are associated with levels of environmental exposure to arsenic, magnesium, mercury, and selenium. Demographic information from REGARDS participants was combined with trace element concentration data from the US Geochemical Survey (USGS). Each trace element was characterized as either low (magnesium and selenium) or high (arsenic and mercury) exposure. Associations between demographic characteristics and trace element concentrations were analyzed with unadjusted and adjusted logistic regression models. Individuals who reside in the Stroke Belt have lower odds of high exposure (4th quartile) to arsenic (OR 0.33, CI 0.31, 0.35) and increased exposure to mercury (OR 0.65, CI 0.62, 0.70) than those living outside of these areas, while the odds of low exposure to trace element concentrations were increased for magnesium (OR 5.48, CI 5.05, 5.95) and selenium (OR 2.37, CI 2.22, 2.54). We found an association between levels of trace elements in the environment and geographic region of residence, among other factors. Future studies are needed to further examine this association and determine whether or not these differences may be related to geographic variation in disease.  相似文献   

17.
火焰、石墨炉原子吸收法测定地表水中铜和镉   总被引:3,自引:0,他引:3       下载免费PDF全文
对浓缩火焰原子吸收法和石墨炉原子吸收法测定地表水中痕量铜和镉的结果作了比较。试验结果表明,两种方法测定结果间无明显差异,加标回收率为88.7%~103%,可互相替代,等效使用。  相似文献   

18.
A survey is given of the possibilities and restrictions of (bio)monitoring trace metals in the salt marsh as exemplified for the Scheldt estuary. The objectives for monitoring in the salt marsh are enumerated as well as the requirements they should meet. Previous studies on monitoring trace metals in the salt marsh are reviewed.Problems in monitoring trace metals in the soil subsystem are due to variations in the input of these metals, the type of esturine circulation and the distribution of physical and chemical conditions in the salt-marsh deposits. The degree of metal enrichment and the spectrum of chemical speciation of the metals by means of a sequential extraction procedure is shortly discussed.Problems in monitoring trace metals in salt-marsh plants are discussed with respect to the bioavailability of these metals from soil and inundation water as sources of contamination, the allocation and seasonal variation in metal accumulations, and the role of adhesive particulate matter carried on the shoots by the floods. Aster tripolium seems to be a good species for biomonitoring trace metals in the vegetational component of the salt-marsh ecosystem.Communication Nr. 346.  相似文献   

19.
Major environmental impacts of opencast mining are degradation of landscape and aesthetics of the area by creating huge overburden dumps and deep voids at the mining sites. These overburden dumps are characterised by high rock fragment contents, low moisture retention capacity, higher bulk density, low nutrients, lower pH and elevated metal concentrations. Overburden dumps are reclaimed by tree species for stabilising as well as pollution control and overall improvement of the visual aesthetics. A field study was carried out in the old reclaimed coal mine overburden dumps at KD Heslong project, Central Coalfields, India to study the physico-chemical changes in the reclaimed overburden dumps and determines the magnitude of trace elements accumulation in the planted tree species. Total, bioavailable and acid extractable trace metals concentration in minesoils of overburden dump and topsoil in the mining areas was compared with undisturbed soil. The study showed that tree plantation improves the moisture contents, bulk density, pH and overall nutrient contents of minesoils. The study revealed that lower pH in the minesoils increases the bioavailabity of metals but concentration were found within toxic limits. However, ratio between total and bioavailable metals was found lower in overburden dumps than topsoil due to low pH and lack of organic matter. Out of six tree species studied, Bambusa shows highest accumulation of Fe and Cr. Bioaccumulation coefficient for Cr and Zn was found 74 times in Bambusa and 83 times in Dalbergia sissoo. The results of the study underscore the need for close monitoring of trace elements in reclaimed overburden dumps. Tree species like Dalbergia sissoo, Eucalyptus, Cassia seamea, Acaccia mangium and Peltaphorum were found to be the best species for bioreclamation of overburden dumps.  相似文献   

20.
The biogeochemical and ecological assessment of the industrial city territory including urban soils and trees was carried out. Chemical (macroelement and microelement) composition of the city soils, morphological and biochemical properties of the linden leaves, possible impact of de-icing salts on soil and tree state, the correlation between the content of trace elements, and the S-containing plant compounds (phytochelatins) were included in the assessment. It was found that concentrations of trace elements in the soils near road with intensive traffic are changed from the soils, located at a distance of 40–50 m from the road. They have higher concentrations of As, Fe, Mn, Se, and Sr and lower concentration of Zn. The linden leaves from the roadside were characterized by the increase in As, Cu, Fe, Zn, and Cr and sharp decrease in the Mn and Sr concentrations. The analysis of soil water extracts showed a slight decrease of pH and low content of Ca, Mg, K, and Na for the distant sites. The phytochelatin test of linden leaves was weakly effective as well as asymmetry degree study of leaf lamina. The main differences were observed in the damage symptoms of leaves (chlorosis and necrosis) and the content of pigments (chlorophyll and carotenoids). The biochemical and ecological assessment of soils and trees showed relatively satisfactory ecological state of the investigated area in Moscow. The data obtained shows the weak local impact of the application of de-icing salts and automobile emissions.  相似文献   

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