Use of Flame Atomic Absorption Spectroscopy and Multivariate Analysis for the Determination of Trace Elements in Human Scalp

The analysis of trace elements in human hair for use as biomarkers continues to generate considerable interest in environmental and bioanalytical studies, medical diagnostics, and forensic science. This study investigated the concentrations of essential and toxic elements (Fe, Mg, Ca, Cu, Zn, Cr, Cd, and Pb) using flame atomic absorption spectroscopy (FAAS) in human scalp hair obtained from subjects living in Forsyth County, North Carolina, USA. The influence of age, sex, race, and smoking habits on the levels of trace elements in the hair samples were also investigated. Additionally, analyses were subjected to a statistical, regression, and principal component analysis to evaluate inter-elemental association and possible pattern recognition in hair samples. Furthermore, Ca/Mg and Zn/Cu ratios, which are often used to evaluate the degree of Ca and Cu utilization in humans and as markers for various health related issues including, atherosclerosis, hypertension, insulin sensitivity, and pancreatic cancer, were calculated. The overall mean concentrations of Fe (25 μg/g), Ca (710 μg/g), Mg (120 μg/g), Zn (190 μg/g), Cu (12 μg/g), and Cr (0.20 μg/g) were found in hair samples. The trace element concentrations varied widely in hair samples as demonstrated by large range of concentrations obtained for each element. However, levels of Cd and Pb elements of <0.030 μg/g were detected in hair sample. In general, the levels of the trace elements in hair samples were poorly correlated. However, significant correlations were found between Ca and Mg (r = 0.840, p = 0.05). The levels of Fe, Ca, Mg, Zn, Cu, and Cr in hair samples and the calculated Ca/Mg and Zn/Cu ratios were found to be largely correlated with age, race, sex, and smoking habits.

Preliminary study of the correlation between trace elements in human hair, liver and kidney by proton induced X-ray emission analysis

This paper deals with the determination of trace elements in normal human hair, liver and kidney by Proton Induced X-ray Emission (PIXE) analysis. Sampling, specimen preparation and experimental procedures are described in detail. The accuracy of our system has been checked up with the determination of standard reference materials. The preliminary results on correlations between trace elements in human tissues are discussed. Application of the method described in the paper gives evidence in favour of the PIXE as a good tool on environmental life elements and health studies.

Selected Trace Elements in Domestic Water Boreholes and Their Implications on Human Health, in Huruma Estate, Eldoret Municipality, Uasin-Gishu County, Kenya

Trace elements constitute less than 1% of the rocks in the crust (Stumm and Morgan, 1991). In the human body, they constitute less than 100 mg/kg (0.01%). These elements are released to the environment naturally by weathering and volcanic activities (Flint and skinner, 1997). It has been observed that trace elements are greatly absorbed and retained in the body when in liquid diet. This phenomenon also influences the risk to human health, especially of infants and children whose immature digestive system further promote absorption of toxic heavy metals. The study was based on the analysis of domestic borehole water supplies in Huruma estate of Eldoret Municipality for selected trace elements and their implications on human health. The boreholes were systematically selected for sampling points and trace elements, Cr, Cu and Se analyzed using AAS. Statistical analysis for mean, standard deviation and confidence interval limits was done using SPSS. The statistical t-test was used to test for significance differences at (p = 0.05). The graphs were drawn using the Microsoft Excel package. The resulting data obtained from analysis were compared with WHO data for drinking water. In the study, the mean values of the following parameters were as follows: Chromium 17.9 μg/L, Copper 563 μg/L and Selenium 22.7 μg/L. There was a significant difference at 5% level of significance (p = 0.000) in all the parameter values among the sampling points in Huruma estate. The above mean values were far below the WHO recommended limits for drinking water. It was concluded that the borehole water from Huruma was fit for drinking and therefore could not cause cancer and cardiovascular diseases. However, borehole water should be used if other water sources (tap water etc.) were not available. All the industries near Huruma estate should carefully analyze and regularly monitor their liquid waste effluents to ensure that no harmful discharges get into the soil.

Measurement of the Trace Elements Cu, Zn, Fe, and Mg and the Ultratrace Elements Cd, Co, Mn, and Pb in Limited Quantity Human Plasma and Serum Samples by Inductively Coupled Plasma-Mass Spectrometry

In public health studies limited volumes of blood are often collected and stored for future hypothesis testing. Archived samples are irreplaceable and therefore it is valuable to develop analytical techniques that require minimal sample vo-lume. This work describes the measurement of trace elements Mg, Cu, Fe, Zn and ultratrace elements Cd, Co, Mn, Pb in limited quantity (150 μL) human serum or plasma samples. Samples were digested using a hotblock and analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The analytical method was evaluated using a quadrupole (Q) and sector field high resolution (SF) instrument to analyze trace elements in Seronorm? quality control serum material. The method was used to analyze 1888 blinded human plasma samples which were archived for the National Cancer Institute from the Nutrition Intervention Trial in Linxian China. The inductively coupled plasma method was capable of accurately analyzed limited quantity samples of human serum and plasma for the trace elements Mg, Cu, Fe Zn and the ultra trace elements Co, Mn and Pb. The concentration of Cd in human plasma samples was below the level of detection for 75% of the samples analyzed.

Measurement of trace element content in bone samples using long-lived neutron activation products and high-resolution gamma-ray spectrometry

A nondestructive instrumental neutron activation analysis with high-resolution gamma-ray spectrometry of long-lived radionuclides was developed and used for measurement of trace element contents in samples of bone to determine health and diseases. Using this method, the silver(Ag), cobalt(Co), chromium(Cr), iron(Fe), mercury(Hg), rubidium(Rb), antimony(Sb), selenium(Se), and zinc(Zn) mass fractions were estimated in bone samples from 27 patients with intact bone(12 females and 15 males, aged from 16 to 49 years) who had died from various non-bone-related causes, mainly unexpected traumas,and from 5 patients with chondroma(2 females and 3males, 15–42 years old), obtained from open biopsies or after operation. The reliability of the differences in the results between intact bone and bone affected by chondroma was evaluated by a parametric Student's t test and a nonparametric Mann–Whitney U test. It was found that in the bone affected by chondroma, the mean mass fractions of Co, Cr, Fe, Se, Sb, and Zn were significantly higher than in normal bone tissues. In the neoplastic bone, many correlations between trace elements found in the control group were no longer evident. This work revealed that there is asignificant disturbance of the trace element metabolism in bone affected by chondroma.

Method and portable facility for measurement of trace element concentration in prostate fluid samples using radionuclideinduced energy-dispersive X-ray fluorescent analysis

A facility and method for109 Cd radionuclide-induced energy-dispersive X-ray fluorescent(EDXRF) were developed to determine the Fe,Zn,Br,Rb,and Sr concentrations in the specimens of human prostatic fluid.Specimens of expressed prostatic fluid were obtained from 51 men(mean age 51 years,range 18–82 years) with apparently normal prostates using standard rectal massage procedure.Mean values(M ± SEL) for concentration of trace elements(mg L^(-1)) in human prostate fluid were:Fe 9.04 ±1.21,Zn 573 ± 35,Br 3.58 ± 0.59,Rb 1.10 ± 0.08,and Sr B 0.76.It was shown that the results of trace element analysis in the micro-samples(20 l L) are sufficiently representative for assessment of the Fe,Zn,Br,and Rb concentration in the prostate fluid.The facility for109 Cd radionuclide-induced EDXRF is comparatively compact and can be located in close proximity to the site of carrying out the massage procedure.The means of Zn and Rb concentration obtained for prostate fluid agree well with median of reported means.For the first time,the Fe and Br concentrations,as well as the upper limit of the Sr concentration,were determined in the human prostate fluid.

DISTRIBUTION OF SOME ELEMENTS IN HUMAN HAIR AND ORGANS DETERMINED BY NAA

Twenty four male autopsies were obtained from Shanghai. The samples of liver, lung, kidney cortex, brain and scalp hair were collected from the autopsies. The elements As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Rb, 8, Se and Zn were determined by neutron activation analysis (NAA). The present study provides the elemental levels of different tissues for normal male adults. The distribution pattern of elements was discussed. Great difference on distribution of some elements in different tissues was observed.

PREPARATION AND CERTIFICATION OF THE HUMAN HAIR REFERENCE MATERIAL

The preparation of the human hair reference material and the steps taken to confirm its homogeneity and stability as well as its certificatipn are described. Certified values for 17 elements, which are of importance for human health, and reference values for the other 13 elements are provided for this material.

交通事故痕迹物证综合鉴定案例分析

伴随着当前社会经济的持续快速发展,人民的生活水平获得了持续的提升,我们国家机动车当前的保有量也持续提升,截至2022年底,全国机动车保有量达4.17亿辆,其中汽车3.19亿辆;小型轿车成为了普通民众日常出行以及旅游所不能够缺少的交通工具,为人们提供了了极大便利的同时,道路交通事故也不断的增加;随之,道路交通事故中所涉及的相关司法鉴定工作也增加,所司法鉴定为办案人员提供专业性鉴定意见,为事故责任认定提供重要的参考证据;交通事故司法鉴定中尤以车辆痕迹鉴定为重要内容,尤其涉及是否接触问题,更需要专业人员通过多方面痕迹物证对其进行技术鉴定。笔者结合近些年司法鉴定工作经验,探讨痕迹物证在交通事故痕迹物证综合鉴定的应用及案例分析。

基于虚拟仿真的同步器齿毂误差溯源实训系统

该文依托某企业同步器齿毂智能产线在线测量设备,并结合数字孪生技术的虚实映射特点,构建了同步器齿毂误差溯源的虚拟仿真实训系统。该系统通过对在线测量设备比对仪Equator^(TM)的物理实体、虚拟实体、质量管控系统和孪生数据等部分进行交互分析,提出一种基于数字孪生的齿毂误差溯源模型,在实验教学平台上实现了智能制造产线误差溯源的实践训练。该系统还可以对齿毂在线测量的实时状态进行监控和模拟,使用深度学习等智能化方法追溯齿毂误差的原因,验证了实训系统的有效性。

上海地区母乳成分调查

目的 了解当前上海地区母乳中各种成分的含量 ,为健康教育提供依据。方法 收集上海市三区一县 12 0名产妇的乳汁 ,测定其蛋白质、脂肪、碳水化合物、钙、锰、钠、钾、磷、氯、铁、铜和锌的含量 ,并对产妇作膳食调查。结果 上海地区母乳中蛋白质、锰、钠、钾、氯、铁和铜含量高于参考值 ,且市区较郊区更高 ,差异有显著性 ;脂肪、钙和锌含量低于参考值 ,郊区更明显 ,差异有显著性 ;碳水化合物和磷含量接近参考值 ,市区与郊区相比 ,碳水化合物的差异无显著性 ,磷的差异有显著性。结论 上海地区母乳中脂肪、钙和锌含量偏低 ,钠和氯含量明显偏高 ,建议孕、产妇及乳母应适当增加脂肪、钙和锌的摄入 。

人发微量元素含量用作环境的生物指示研究

用仪器中子活化分析方法测定了１９９４年和１９９６年两次采集的北京石景山地区２０—４０岁正常男 性头发样品中微量元素的含量，用ｔ检验方法比较这两批人发样品测定值的差异，观察该地区的环境 变化趋势及该人群营养状况的变化；同时还与国内外报道的有关数据进行了比较，用以说明人发中的 微量元素含量在用作环境的生物指示研究方面的意义。

内蒙古慢性砷中毒地区少年头发中微量元素含量研究

报道了1994～1995年在内蒙古呼和浩特市土默特左旗慢性砷中毒病区采集的少年头发样品中砷等十多种微量元素含量的仪器中子活化分析结果，并与北京地区同年龄段少年发样中测得的值进行了比较。发现前者除发砷含量明显高于后者外，两者在其他许多微量元素含量上也存在显著性差异，特别是慢性砷中毒地区少年头发中稀土元素（如La；Sm）和重金属元素Fe、Co、Cr等的含量均明显高于对照区。所得结果为研究呼和浩特市慢性砷中毒地区人群头发中微量元素的含量与该地区环境状况的关系，从而深入探讨这一地方病在该地区高发的原因提供了有意义的信息。

ICP-AES测定云南楚雄糖尿病患者发样微量元素的研究

探讨微量元素与糖尿病间的关联性及临床意义。采用ICP-AES等离子体发射光谱仪测定了楚雄地区糖尿病患者人发中11种元素,采用2,3-二氨基萘荧光法测定发样中的硒元素。选取糖尿病患者120例,对照组35例。糖尿病组发样中常量元素Ca、Mg低于对照组,P高于对照组;除Cd、Cr、Fe外,微量元素Zn、Se、Ni、Mn、Cu等5种元素低于对照组,并有显著差异(P<0.01)。糖尿病组间性别比较数据显示男性除发Ni、Mn、P外,其余元素含量均低于女性,其中发锌远低于女性。3个不同年龄段糖尿病人群的微量元素含量变化显示Fe、P2种元素随年龄增加含量增高;Mg、Cd2种元素随年龄增加含量减少;其余各元素变化情况为Fe、P元素在老年组中较高,Cu、Cd、Mg较低;Mn、Cr、Cu元素含量在中年组中较高,而Zn、Se略低;Zn、Se在青年组较高,而Mn、Cr低。城市人群发中Zn、Cd、Cu、Mg、Ca含量比农村人群高;Se元素含量二者间差别也不大,其余元素含量均低于农村人群。楚雄地区糖尿病患者发中Zn、Se、Mg、Mn4种元素水平低,楚雄地区糖尿病患者致病原因可能与地区属低Se水平和患者体内硒水平低有关。

中子活化法研究砷中毒病区人发中微量元素的分布

应用中子活化分析法测定了地方性砷中毒病区病人头发中23种微量元素的质量分数,并与北京健康人发中微量元素的质量分数进行了比较。结果表明:As,Fe,REE,Ba,Br,Sb在重病患者发中的质量分数最高,轻病患者次之,正常人最低;而Se,Ca在健康人发中的质量分数最高。用t检验方法比较这三组之间人发中微量元素的差异,发现上述元素在三组中,人发之间均存在明显差异(P<0 05或P<0 001)。并且头发中As质量分数越高,病人病情越严重。Fe,REE和Ba等微量元素可能加重砷的中毒,而Se,Ca和Co可能拮抗砷的毒性。

环境地球化学与人体健康关系的探讨

以研究成果资料为基础 ,探讨了环境地球化学与人体健康的关系 ,试图以医学与环境地球化学相结合和元素地球化学分布与生态学特征相结合的方式进一步阐述这一问题 ,揭示其内在联系和规律。最后从营养角度讨论了强身健体。

ICP-MS检测铊中毒事件中的痕量铊

本文建立了一个使用 (HNO3+HClO4)和 (HNO3+H2 O2 )湿法消解样品 ,用电感耦合等离子体质谱法 (ICP -MS)测定人尿、血清和脏器样品中痕量铊的方法。选择了仪器最佳操作参数 ;选用铼 (Re)作内标元素 ,可补偿基体效应。方法的检出限为 0 .0 0 8ng mL ,加内标回收率为 93～ 1 1 0 % ,相对标准偏差 (RSD)为1 .8～ 5.7%。

不同地区人发中微量元素的测定与生存环境的比较研究

采用高压密封消化罐对人发样品进行处理,将化学计量学应用于ICP-AES法测定了人头发中20种微量元素的含量。该方法操作简单、快速、灵敏度高,准确性好,且多元素同时测定,回收率在94.07%～107.60%之间。相对标准偏差小于3.49%。通过对不同地区不同年龄1600人头发的测定结果,探讨了营养、环境污染等因素对人体健康的影响,从而对其生存环境进行比较研究。

用中子活化分析法研究25种元素在人体肝脏亚细胞组分中的分布

采用差速离心分离技术与中子活化分析法(NAA)相结合的方法分析了人肝25种元素,并用标准参考物保证结果的准确性.分析结果表明,大多数元素在各亚细胞组分中并非均匀分布.As、Au、Co、I、Mg、Mo、Sb、Sc在细胞核和线粒体浓度最高.Al、As、Au、Ba、Fe、I、La、Mg、Mn、Sb、Se在胞液中浓度最低,生物体内主要以离子形式存在的Br、Cl、K、Na则在胞液中浓度最高.值得注意的是,As在细胞核中大量聚集,是其它组分的2～4倍;而La与Fe则在微粒体中富集.