Trace element profiles in the hair of Nasopharyngeal carcinoma (NPC) patients

The trace element profiles of the scalp hair of NPC patients, aged between 30 and 69, were measured using neutron activation analysis and compared with those of normal healthy people within the same age bracket. The washing method of using detergent and washing powder was found to be comparable to that of using ether. Difference in the mean concentration of each element in the two groups was tested by Student's t-test. A significantly lower value of strontium (Sr) and significantly higher values of arsenic (As), iron (Fe) and vanadium (V) were found in the hair of NPC patients. The relative values of As and Fe found were consistent with the results of other findings on NPC patients, using different measuring methods. The V content in the hair of NPC patients was three times that of healthy people.     

Quality control in hair analysis: A systematic study on washing procedures for trace element determinations

Trace element analysis of human hair is widely used to provide an indicator of body burden, but there is a major problem associated with preparation. The washing procedure adopted before analysis represents still a critical point which deserves particular attention. This study aimed at comparing the efficiency of the most commonly used washing methods to identify the procedure which allows for satisfactory removal of external contamination alone. As results depend strongly on the element, toxic (Cd and Pb), essential trace (Cr, Cu, Se and Zn) and major (Ca, K and Mg) elements were tested. The comparison was carried out with six different methods which include use of ionic and non-ionic detergents, organic solvents, chelating agents and sonication. Removal efficiency varied according to the element and pretreatment, the highest being observed for EDTA and the lowest for sonication. Unsatisfactory results were found using an acetone/methanol mixture for the potential contamination caused by it. Organic solvents showed the highest removal efficiency for K and toxic elements, and seemed to be effective in removing a limited but significant fraction of element incorporated in the lipid matter of hair. The ionic detergent Na lauryl sulphate, instead, was more effective for essential elements, but also triggered a higher analytic variability. As detergents appear to remove only external contamination, a non-ionic detergent such as Triton X-100 is proposed as a reliable alternative to the acetone method recommended by IAEA. Practical advantages are safe working conditions, rapidity of application and reduction in costs.     

Effects of various washing procedures on the chromium content of human scalp hair

The effects of four wash procedures on the concentration of chromium in a pooled sample of human scalp hair are compared. The wash solutions examined are Triton X-100, sodium lauryl sulphate, acetone, and a mixture (1 + 1) of hexane and ethanol. The plateaux reached for hair chromium concentration are functions of the number of washings, and are characteristic for each wash solution. The wash procedure recommended involves two 20-min washes with aqueous 1% sodium lauryl sulphate solution after a hexane rinse.     

Preparation of Hair and Nail Samples for Trace Element Analysis

Abstract

The method of washing of human hair and nail samples is examined by neutron activation and γ-ray analysis. The amounts of Na, K, Br, Au, Zn and La that are removed by successive washings determine the optimum number of washing for removing these trace elements as surface contaminants. A total solution contact time with the nails is 5 minutes, and leaching effects are observed after 6 washings.     

Nuclear-based methods for the analysis of trace element pollutants in human hair

The trace element composition of human hair is a suitable indicator of exposure to trace element pollutants. During the implementation of an international research programme, coordinated by the IAEA, on the use of nuclear methods for detecting trace element pollutants in hair, much valuable information was collected both on normal levels of trace elements and on increased levels caused by pollution. As a result of reviewing and comparing the data, interesting observations relating to the spread of concentrations were made. Standardized procedures were elaborated for a number of analytical techniques as well as for pre-analytical preparations in the analysis of hair. Paper presented at the Second Meeting on Nuclear Analytical Procedures, Dresden (GDR), 19 to 23 March 1979.     

Determination of trace element levels in human scalp hair in occupationally exposed subjects by XRF

Trace element levels in hair of individuals living in urban areas were determined by energy dispersive XRF. Two groups of subjects were investigated, the first group was assumed to be from a healthy environment, the other one was exposed to a high level of contamination due to working conditions. The results were compared to data reported in the literature. The concentrations of Ca, Fe, Cu, Zn and Pb in the scalp hair were determined and the correlation between hair trace element levels and environmental effects was discussed. The results given by the second group show that environmental exposure effects hair trace element levels which are related to body trace element concentrations.     

Investigation of elemental models in senile dementia and depressives using neutron activation analysis

Instrumental neutron activation analysis has been used to determine the concentration of a range of elements in hair and blood samples, separated into erythrocytes and plasma, obtained from two groups of women, senile demented (9) and depressives (16), and their respective controls (17 and 9). The results suggest that the senile dementia group has significantly higher Al concentrations in erythrocytes and hair relative to the controls but no significant correlation between the aluminium content of hair and that of blood exists. Further, Zn concentrations determined in the erythrocytes and plasma of these subjects were lower compared to the control values. Vanadium levels above our detection limit for the element were found in seven cases out of a total of sixteen in the depressive group. Vanadium was also found to be at higher concentration in the hair of the depressive group compared to the controls. Again no significant correlation was found to exist between the concentration of vanadium in hair and in erythrocyte sample for these seven subjects.     

头发检测与疑难病诊断

综述了我国用头发诊断疑难病,包括恶性肿瘤、心脑血管疾病、尘肺的研究概况。20余年来,中国科技人员创造了4类利用头发微量元素谱诊断疾病的方法。18项研究报告表明,头发微量元素谱可将癌症病人与健康人正确区分开来,为临床癌症诊断奠定了坚实的实验基础,也为利用头发样本代替血液样本作人群癌症筛查提供了理论依据;11项研究结果表明,借助头发微量元素谱,可相当准确地判别待测样本的健康属性,可以诊断和预报疾病,可以筛选高危人群,对心脑血管病的早发现、早诊断、早治疗具有重要的潜在应用价值;9项研究结果证明,测量头发元素,建立判别方法,可以从待检样品准确诊断尘肺患者和找出尘肺高危人群,并可提早3～5年对尘肺的发生作出预报。实践表明,头发检测是疑难病筛查的一种简便、经济、实用、有效的新方法。     

Preparation of radial hair sections for element profile measurements with a proton microprobe

A new technique has been developed to prepare radial hair sections for element profile analysis using a proton microprobe (PM). The technique makes use of equipment and supplies standard in histological electron microscopy laboratories. In addition to obtaining radial hair slices, adjacent 1 m thick slices can be acquired for comparative light microscope viewing. With these adjacent optical slices, element profiles of transitional phase and irregularly shaped hair are easily studied. Selected radial sections of C57L/J mouse hair, used to represent this technique, showed element distribution profiles largely similar to their histological counterpart in human hair.     

头发元素分析的科学意义及医学应用价值

对近100年来头发元素分析发展历史作了简要回顾，并从头发元素水平代表身体元素总体水平、头发元素含量可以准确测定，以及头发元素分析可用于医学诊断等三个方面论述了头发元素分析的生物学基础及临床意义，重点介绍了中国科学工作者在实验研究和临床实践中的探索和发现。科学实践证明，头发元素分析不仅为揭开古代头发神话提供了解释基础，也为头发的现代应用提供了可靠工具和科学依据。     

New human hair certified reference material for methylmercury and trace elements

A new human hair certified reference material (NIES CRM No. 13) for mercury speciation and trace element analysis was prepared at the National Institute for Environmental Studies (NIES), Environmental Agency of Japan. Scalp hair from Japanese males, which is identical with the original material for the previous human hair CRM (NIES CRM No. 5), was used. Special attention was paid to reduce contamination from a grinding vessel during the preparation procedure. A newly-prepared ceramic/Teflon disc mill was used for cryogenic grinding of the hair. 1, 000 bottles (3 g each) were produced after sieving and blending of the hair powder. Certified values for total mercury and methylmercury, as well as other trace elements of toxicological and nutritional significance (antimony, cadmium, copper, lead, selenium, and zinc), were determined based on analyses from extensive collaborations. Reference values for 12 elements (aluminium, arsenic, barium, calcium, cobalt, iron, magnesium, manganese, silver, sodium, sulfur and vanadium) were also given.     

826例儿童发铅、锌、铜、铁、钙含量分析

探讨了东乡县儿童体内微量元素情况。对826例儿童发铅、锌、铜、铁、钙检测结果分各年龄组进行了分析。结果表明,826例儿童中发铅含量超标512例,占61．99％;发锌含量低标604例,占73．1％;发铜含量低标46例,占5．6％;发铁含量低标95例,占11．5％;发钙含量低标116例,占19．6％,占19．6％。5种元素含量与年龄有关,随着年龄增大,发铅、锌、铜、钙含量下降,发铁含量上升。分析表明,儿童铅污染、锌、钙缺乏程度相当普遍且严重。在儿童生长发育期进行常规的微量元素检测非常必要。     

Selenium Determination in Biological Matrices

In this study, we discuss some relevant aspects concerning the determination of selenium in biological materials with special reference to fluorometry and hydride generation atomic absorption spectroscopy (HG-AAS) techniques. The two methods may be applied without modifications to the analysis of Se in a wide spectrum of specimen types, and we describe their reliability in serum and hair analyses. Thirty-six independent control serum samples, the concentrations of which were unknown to the analyst, were analyzed in duplicate using both techniques in the Italian External Quality Assessment Scheme (EQAS). Accuracy was assessed by comparing Se values with those previously assigned by the organizers of the scheme using graphite furnace atomic absorption spectrometry (GF-AAS), which is the most frequently used technique for selenium determination in serum among the participants in the Italian EQAS. The results confirmed that fluorometry has a higher degree of accuracy than HG-AAS: the mean differences between observed and expected values were 1.5 μg/liter (95% confidence interval, −1.06 to 3.97) for fluorometry and −1.1 μg/liter (95% confidence interval, −5.05 to 2.76) for Hg-AAS. We also report some results obtained for the determination of Se in hair. Since a critical step in hair preparation is the pretreatment for removal of external contamination, we compared six different washing procedures. In general, Se is poorly leached from hair, but the efficiency of removal differed with the substance used, ranging from 0 to 13% of the original content. A nonionic detergent like Triton X-100 offers the advantage of safe working conditions and a substantial reduction in costs compared with organic solvents. Lastly, in a consistent group (n= 131) of women, Se in hair was found to be strongly reduced by the use of dye (389.9 ng/g vs 498.7 ng/g,P< 0.001). We recommend recording information on cosmetic treatments when hair is collected to evaluate Se reference values in epidemiological studies.     

Effect of wool keratin proteins and peptides on hair water sorption kinetics

Most beauty care products and treatments primarily affect the cuticle layers of hair fibers. The resulting damage has an adverse effect on hair water absorption. Water changes a wide variety of properties of human hair and is therefore of fundamental interest. Wool proteins are mild, natural, biodegradable, and sustainably produced with multiple functionalities and potential for use in the personal care and detergent market. In this study, the effect on hair water sorption of two types of keratin samples obtained from wool is investigated. Modifications of hair water sorption due to a bleaching treatment have been demonstrated, with lower values of water sorption capacity and an increase of the fibers permeability. Applications of keratin peptides and proteins to bleached hair improved the water sorption properties of the fibers and reduced their permeability.     

New human hair certified reference material for methylmercury and trace elements

 A new human hair certified reference material (NIES CRM No. 13) for mercury speciation and trace element analysis was prepared at the National Institute for Environmental Studies (NIES), Environmental Agency of Japan. Scalp hair from Japanese males, which is identical with the original material for the previous human hair CRM (NIES CRM No. 5), was used. Special attention was paid to reduce contamination from a grinding vessel during the preparation procedure. A newly-prepared ceramic/Teflon disc mill was used for cryogenic grinding of the hair. 1,000 bottles (3 g each) were produced after sieving and blending of the hair powder. Certified values for total mercury and methylmercury, as well as other trace elements of toxicological and nutritional significance (antimony, cadmium, copper, lead, selenium, and zinc), were determined based on analyses from extensive collaborations. Reference values for 12 elements (aluminium, arsenic, barium, calcium, cobalt, iron, magnesium, manganese, silver, sodium, sulfur and vanadium) were also given. Received: 8 February 1996/Accepted: 4 April 1996     

Study of hair element content from an urban Bulgarian population using NAA assessment of environmental status

In this preliminary study, scalp hair samples from 36 individuals resident in Sofia, Bulgaria, were analysed and Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, F, Fe, Hg, I, K, La, Mg, Mn, Mo, Na, Ni, Rb, S, Sb, Sc, Se, Sn, Sr, Ti, V, W, and Zn were determined. Instrumental neutron activation analysis (INAA) methods were used. Three washing procedures.: distilled-deionised water; acidacetone-water; and Triton X-100 detergent-water, showed a variable elemental change strongly dependent on the procedure used. More than 18 elements (Al, As, Ba, Ca, Ce, Cl, Co, Cs, F, Fe, I, K, La, Mo, Na, Ni, Sb, Sc, Sr and V) were easily removed by water-washing. Triton X-100 detergent was more effective in removing Ag, As, Au, Cl, Cs, K, Na and Rb; but not Hg. Only S and Zn were strongly incorporated in the hair structure (less than 10% being removable by any washing technique). There is no significant age correlation with any element between the various hair treatment groups. Elevated cadmium levels were found in the hair of smokers (0.711–4.913 g/g Cd) compared with nonsmokers (0.568–2.681 g/g Cd). Comparison of the elemental data for distilled water-washed hair and studies from Oxford, England and Hastings, and Hastings, New Zealand (using the same INAA method) revealed interesting variations dependent on local industrial and nutritional factors.     

老年慢性支气管炎急性发作期病人头发微量元素的测定与分析

为观察老年慢性支气管炎急性发作期头发中微量元素的变化,测定了50例老年慢性支气管炎急性发作期患者和40例正常对照组头发中锌、铁、铜、钙、锰、铅6种元素含量。结果表明,慢性支气管炎急性发作期患者发中锌、铁、铜、钙含量明显低正常对照组（P＜0．01）。提示头发中微量元素减少与慢性支气管炎易反复感染有一定的关系。     

Multielement neutron activation analysis of human scalp hair a local population survey in the Tokyo metropolitan area

Applying instrumental neutron activation analysis, multielement analysis of human hair was carried out to elucidate the levels of various trace element concentrations in hair of local population in the Tokyo metropolitan area. 202 hair samples were collected from the inhabitants classified by sex and five age groups. Using several combinations of irradiation time, cooling time and counting time, forty elements were quantitatively analyzed. The method of analysis for data including samples under detection limit is discussed, assuming that the frequanecy distribution of trace element contents in hair is log-normal.     

360例鼻咽癌患者头发微量元素调查报告

为探讨鼻咽癌患者机体内微量元素的含量，作者对３６０例鼻咽癌患者在放疗前进行头发Ｚｎ、Ｆｅ、Ｃａ、Ｃｕ、Ｎｉ含量的测定，并对各年龄及性别间的微量元素进行对比．结果表明，头发Ｚｎ男性鼻咽癌患者明显高于女性（Ｐ＜０．０１），头发Ｆｅ老年组鼻咽癌患者明显高于青年组（Ｐ＜０．０５），头发钙青年组鼻咽癌患者明显高于老年组（Ｐ＜０．０５），而头发ＣＵ、Ｎｉ各年龄组及性别间均无明显差异。     

Determination of Uranium in Human Hair by Acid Digestion and FIAS-ICPMS

The content of heavy metals in human hair may serve as an indicator of occupational or environmental exposure to metal compounds. However, before such exposure can be determined, the level of the element in a "normal" population must be established. The concentration of uranium in human hair was measured by flow injection — inductively coupled plasma mass spectrometry (FIAS-ICPMS) after acid digestion of the hair samples. All hair samples were rinsed in order to remove external contamination prior to the digestion in a 2:1 solution of concentrated nitric acid and 30% hydrogen peroxide. The limit of detection of the method, for a 50 mg hair sample, was 0.015µg/g, mainly due to the presence of impurities in the hydrogen peroxide. The range of uranium concentration in the initial test group was found to be 0.01–0.18 µg/g. The mean and median values of the entire study population were 0.062 and 0.050 µg U/g hair, respectively. Differences between the following sub-populations: male and female, smokers and non-smokers and people below and above 45 years of age were examined. The only statistically significant difference was found in the latter group (p = 0.03).