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1.
In order to assess the elemental concentration level in a galvanizing industry and alert for the need to assess the outcome of a long-term exposure, scalp hair and toenail samples were used as bioindicators and the industry environment was evaluated through airborne particulate matter. The elemental concentration results have pointed out a high exposure to pollutant at workplaces and a high elemental concentration in biomonitors suggesting endogenous contamination. The majority of the elements determined in airborne particulate matter were also determined in hair and toenail samples. The results evidence the efficiency of these matrixes as biomonitors and the importance to carry out the airborne particulate matter sampling in parallel to these biomonitors mainly in occupational epidemiological studies.  相似文献   

2.
Eleven human hair samples were taken from the Chinese residents of Hong Kong for the study of hair trace elemental level and environmental exposures. Absolute neutron activation analysis and Ge(Li) gamma-ray spectrometry were applied in the determination of the trace elemental level. All results are reported in parts per million except for sulfur and oxygen which are reported in percent. The trace element content of hair from a drug addict was found to be considerably different from other sampled people. Comparison of the normal concentrations of the trace elements of the Chinese residents of Hong Kong was made with those from people of various other national, socio-cultural and environmental backgrounds. It was found that together with a few other trace elements, Ni, Sr, Zr and Hg content of the Chinese Residents of Hong Kong show a higher level than those of the other sampled people.  相似文献   

3.
Hair samples were collected from 20 metallurgical workers (10 males and 10 females) and from 59 control subjects (32 males and 27 females), whose jobs do not indicate a specific occupational exposure. The concentrations of ten minor and trace elements (Al, Co, Cu, Fe, Mg, Mn, Sb, Se, V and Zn) were determined by instrumental neutron activation analysis (INAA). The statistical data distributions, the sex and age influences in these elemental concentrations and the average values obtained for the control group were compared with published data. The effect of occupational exposure to the metallic elements was reflected in elemental composition of hair by significant higher concentration levels of Al, Co, Cu, Fe, Mg, Mn, Sb, V and Zn in the hair of the exposed group, when compared with the control group.  相似文献   

4.
The objective of this study was to evaluate the concentrations of essential and toxic elements in hair of children in Tanzania in order to assess their nutritional status. 141 samples of hair from boys and girls living in Tanzania were analyzed using instrumental neutron activation analysis (INAA). The mean concentration levels of Zn and Cu were lower whilst those of other elements were in the same range as the hair elemental concentrations reported in the literature. The lower concentrations of Zn might be related to the diet of mainly cereals with low animal proteins consumed by most of the Tanzanian population.  相似文献   

5.
Several metals are suspected or known to be involved in neurological disorders such as Alzheimer's disease (AD), therefore, elemental distribution studies have received intense attention for years. The present work focuses on a group of lesser studied elements in this context, alkali metals.Previously, an adequate neutron activation analysis (NAA) method has been developed and applied successfully for the determination of Na, K, Rb and Cs in brain samples of control subjects. This work has been extended to include AD patients, so that average values, distribution patterns and interpersonal variability could be compared and possible correlation between control and AD data could be studied.Despite the merits of the technique, its drawbacks are evident. Therefore, applicability of rapid spectrochemical methods as alternatives has been investigated. ICP-AES has been used for analysis of Li, Na and K. No interferences were observed, but ultrasonic nebulisation was needed for Li quantification. Rb and Cs were measured by ICP-MS with In as internal standard. Agreement between different techniques is found to be good for Na, K and Rb, while Cs values show somewhat higher differences.  相似文献   

6.
Summary Instrumental neutron activation analysis was conducted on PM 10 samples collected in Daejeon city, Korea during September 2001 to May 2002. Our measurement data were analyzed to explain the behavior of particle-bound elemental components in relationship with Asian Dust (AD) events. The results of our analysis indicated that the major crustal elements (e.g., Al, Ca, Fe, K, Mg, and Ti) showed strong enrichment (about 3 to 9 times higher concentration levels) during the AD period accompanied by the increase in the PM 10 levels (e.g., by about 3 times). However, the concentrations of anthropogenically derived elements (such as As, Br, Sb, Se and Zn) exhibited moderate change during the AD period. Hence, the computation of enrichment factor (EF) indicated that the magnitude of EF values during the AD period was even smaller in the case of toxic metals than its non-AD counterpart. The existence of relatively low EF values during the AD period can be attributed to the excessive input of crustal components. The overall results of our study suggest that both absolute and relative elemental composition of aerosol particles can be altered significantly by the AD events.  相似文献   

7.
Nutritional status and toxic elements body burden were evaluated in hair of children living in Zanzibar. 18 samples were collected from Zanzibar town and 19 samples from Nungwi village, which is approximately 64 km from Zanzibar town. The analysis was carried out using instrumental neutron activation analysis (INAA). The concentration ranges obtained in this study overlap with the published elemental values of healthy children of the same age group. The concentration levels of K, Zn, Cu, As and Co in hair of children from Zanzibar town were higher than from Nungwi whereas levels of Mn, Br and Sr were lower.  相似文献   

8.
Biomonitoring of Cr, Fe, Ni, Cu, Zn and Pb in scalp hair of the rural population in Punjab state of India was carried out using TXRF. The objective of the study was to understand their exposure to the trace elements from the local environment. The volunteers having age group 30–45 years were selected from rural region of Punjab. Validity of method was checked by analyzing Certified Reference Materials IAEA-436 and INCT-MPH-2. The results of trace elements analysis in hair samples shows no environmental gradient in the concentration of the elements like Cr, Fe, Ni, Cu, Zn however Pb was observed higher in few volunteers as compared to published value of concentrations in volunteers from Delhi.  相似文献   

9.
An ultrasonic-assisted leaching procedure was developed for the determination of heavy elements (As, Cu, Cd, Pb, and Zn) in Certified Reference Material of human hair (CRM 397) provided from the Community Bureau of Reference (BCR) of the Commission of the European Community. Concentrated nitric acid-30% hydrogen peroxide (2 + 1) was used for the leaching method. The effects of different factors on acid leaching of elements, such as presonication time (without ultrasonic stirring), sonication or exposure time to ultrasound, and temperature of the ultrasonic bath have been investigated. Optimum values of these parameters were selected for the maximum extraction of heavy metals from CRM BCR 397 and human scalp hair samples of normal healthy males. To check the validity of the proposed method, a wet acid digestion method was used to obtain the total elemental concentration in CRM BCR 397 and scalp hair samples. Cu and Zn in leachate and digests were measured by flame atomic absorption spectrometry using a conventional air/acetylene flame, while As, Cd, and Pd were determined by electrothermal atomic absorption spectrometry. Under optimized conditions, the recovery for Zn, Cd, Pd, As, and Cu was 98, 98.5, 97.5, 98.2, and 95%, respectively, of those obtained with the wet acid digestion method.  相似文献   

10.
A number of essential trace elements play a major role in various metabolic pathways and in many diseases like autoimmune, neurological and psychiatric. This study is undertaken with an aim to evaluate the levels of different trace elements in the scalp hair samples of patients suffering from alcohol induced psychosis by particle induced X-ray emission technique (PIXE). It is observed that Fe (p?<?0.0005), Cu (p?<?0.001) are significantly higher in the hair samples of alcohol induced psychosis patients compared to those in normals while concentrations of Mn (p?<?0.005) and Zn (p?<?0.0001) are lower. The concentrations of Co and Ni in the hair samples are found to be in consonance with the concentrations in the normals.  相似文献   

11.
The presence and the concentration of trace elements in hair are subject to variations according to a number of factors. The primary investigations consist in a statistical interpretation of (1) the distribution of the oligo-elements in a homogeneous hair sample, (2) the distribution over one particular head, (3) the evolution in samples taken at successive intervals, (4) the distribution over a population. Our study was mainly concerned in the influence of the time factor, and revealed an unpredictable behaviour of the elements under investigation (As, Sb, Au, Mn, Hg, Cu). There was only one exception: Zn. This unpredictable behaviour of most of the oligo-elements is due to their being influenced by such external conditions as environment, washing, hair dyes, diet and drug intake. The identification of hair samples on the basis of concentrations so inconstant and easily influenced, is a most impromising endeavour. Furthermore the irregularity in distribution of the oligo-elements over the head of one and the same person is not of a nature to make things easier. The existence of these factors not only wellnigh excludes the possibility of an identification, but they furthermore make it difficult to confirm unequivocally that a hair specimen belongs to a given person, to the exclusion of any other.  相似文献   

12.
Lead exposure has received increased attention over the past few decades since it has been shown to have adverse effects on physical and intellectual development in humans. The use of biological tissues such as blood, teeth, hair, and bone for assessment of lead exposure has been previously demonstrated. While analysis of blood for trace metals provides information concerning recent exposure, hair offers insight into a period of several months, and is preferable since it is non-invasively collected and easily stored. The present study analyzed total of 49 ancient hair samples for lead (PbH) using LA-ICP-MS. Samples belonged to an ancient fisher hunter–gatherer culture called the “Chinchorro,” and who occupied regions of the Atacama Desert on the northern coast of Chile from approximately 5000–1500 B.C. and practiced the first-known form of artificial mummification. Several samples from a post-Chinchorro agricultural community (n = 12) ca. 1000–1400 A.D. were also analyzed. A suite of hair standards was developed using contemporary hair from the same region and was subsequently used to make linear calibration functions for lead determination in single strands of hair using LA-ICP-MS. Three linear scans ranged from 500 to 1000 μm were performed for each sample and signal intensities were normalized over 13C. The distribution of lead in the central medulla in a 100 μm cross-section scan of hair strand demonstrated minimal exogenous contamination. Hair lead (PbH) concentrations ranged between 2.2 μg/g and 12.8 μg/g could be accurately quantified with these standards. Twenty one out of 49 samples (43%) showed PbH concentrations higher than the average value of 5 μg/g for unexposed individuals (range 1.1–228.0 μg/g). Median hair lead concentrations by burial sites and are shown in order of decreasing concentration: Morro (13.8 μg/g) > Iquique (6.6 μg/g) > Azapa (4.5 μg/g) > Yungay (4.1 μg/g) > Camarones (2.7 μg/g). Most of the burial sites showed PbH concentrations greater than the normal value for unexposed individuals and outliers heavily influenced average concentrations. The results suggest that the Chinchorro and later agro-pastoral populations were not widely exposed to naturally elevated lead.  相似文献   

13.
This work is an application of energy dispersive X-ray fluorescence (EDXRF) as an analytical technique for trace elemental determination in human membrane and placenta and elemental concentrations correlations in both tissues. Whole samples were collected during the delivery from healthy mothers and full-term pregnancies. The age of the mother was between 25 and 40 years old, and the weight of the infants ranged from 2.56 to 4.05 kg. Samples were lyophilised and analysed without any chemical treatment. No significant differences in elemental content of placenta and membrane samples were observed except for Ca. Very low levels of Se, As and Pb were observed in all the analysed samples. Zn, considered as one of the key elements in newborn health, was not significantly different in the analysed samples, all of which originated from healthy mothers and healthy babies. The obtained values agree with the literature except for Ca, which is much higher in the studied samples.  相似文献   

14.
The intake of leafy vegetables in daily diet is very important to meet our nutritional needs. Vegetables provide the essential elements which are necessary and recommended for human growth. However, due to rapid industrialization and urbanization our environment becomes polluted and this affects the normal growth of agricultural products and composition of environmental species. The elemental concentrations present in the environmental samples are good indicators to assess the toxicological levels due to pollution affects. In the present work we have analysed several vegetable plant samples by instrumental neutron activation analysis to determine the elemental concentrations at major, minor and trace levels. The leafy vegetables like spinach, red leafy veagetable, pui, gourd leaf, lettuce and katoua were chosen as these are extensively consumed by local peple in eastern part of India. We have determined 15 elements in the above mentioned vegetable samples and some of these are essential elements and some are toxic elements. It was found that Na and K were present as major elements, Fe and Zn as minor elements and As, Ce, Cr, Co, La, Mo, Rb, Sc, Sm, Sr as trace elements. The concentration level of Cr was found to be higher than that of recommended value certified by WHO and National environment quality control for human consumption. The validation of our analytical results have been performed by the Z-score tests through the determination of concentrations of the elements of interest in certified reference materials.  相似文献   

15.
In the present paper, for the first time the multielemental compositionof hair samples of Indian populations living in the Xingu Park Reservation,in the Brazilian Amazonic region has been determined, by INAA. Irradiationswere carried out at the Interfaculty Reactor Institute (Delft, The Netherlands)and, using a combination of different irradiation and decay times, about 40elements could be determined in the hair. Previous analysis made at the RadiochemistryDivision of IPEN/CNEN-SP (Brazilian Nuclear Energy Commission) of hair samplesof a Brazilian control population allowed the determination of 20 elements,also by INAA. Comparison of the data obtained for the Indian populations andthe controls showed very significant differences in elemental compositionsfor some elements, like Hg, Mn and Al while for others, like Cu and Zn, theconcentrations were similar. A discussion of the differences found for otherelements also is made in the present paper.  相似文献   

16.
Summary It has been observed that among the seven municipalities of the Island of Krk the three in the central part of the island have increased disease incidence rates for the five groups of diseases: (a) neoplasm, (b) diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism, (c) endocrine, nutritional and metabolic diseases, (d) mental and behavioral disorders and (e) diseases of the circulatory system. One of the etiological factors is assumed to be the influence of the geochemical environment. The average element concentration values of six trace elements (Mn, Fe, Ni, Cu, Zn and As) for the geochemical environment in the individual municipalities were determined by XRF analyses of soil, plant, potable water and hair samples. The data on disease incidence rates for the individual municipalities, from 1997 to 2001, have been obtained from the Public Health Institution in charge of monitoring population health on the island. Diseases' groups have been defined by the WHO methodology. The GPS-GIS methodology was used to obtain maps of trace elements in different matrices and disease incidence distributions. Data analyses were performed by multivariate statistical methods (principal component analysis and cluster analysis). It has been shown that the concentration levels of the elements could be related to disease incidence rates.  相似文献   

17.
The ablation interaction between a laser and solid samples, which affects the analytical performance for laser ablation inductively coupled plasma atomic emission spectrometry (LA-ICP-AES), was studied. The emission intensities of elements observed by LA-ICP-AES (LA-ICP-AES element signal intensities) for different solid samples were measured under different laser defocusing conditions with a fixed laser output energy. It was found that the optimum laser defocusing conditions were dependent on the different solid samples with different sample characteristics, and also on the different elements with different elemental characteristics in each solid sample. A low-alloy steel, pellets containing different Fe concentrations (0 - 100% Fe pellet), and a pond sediment pellet were used as different solid samples. The variations of the LA-ICP-AES Fe signal intensities observed under different laser defocus conditions were completely different between the low-alloy steel and the pond sediment pellet. The changes in the LA-ICP-AES Fe signal intensities for 90 and 100% Fe pellets were similar to that of the low-alloy steel. However, pellets with lower Fe concentrations (less than 70%) showed different trends and the defocusing behavior became closer to that of the pond sediment pellet. The LA-ICP-AES signal intensities of other elements were also evaluated, and were compared for different solid samples and different defocusing behavior. It was observed that the changes in the LA-ICP-AES signal intensities of almost all elements in the pond sediment pellet showed a similar trend to those of Fe for different laser defocus positions; that is, the elemental fractionation for these elements in the pond sediment pellet seemed to be relatively small. On the contrary, it was found that the LA-ICP-AES Si, Ti, and Zr signal intensities for low-alloy steel showed different trends compared to those of other elements, including Fe, under different defocusing conditions; that is, the elemental fractionation observed for the low-alloy steel was larger than that of the pond sediment pellet. From these results, different ablation interactions between the laser and the different solid samples were considered, and attributed to the sample characteristics, such as the matrix, hardness, and conductivity. Elemental fractionation was attempted to be explained by using elemental characteristics, such as the melting point and ionization energy of the elements.  相似文献   

18.
Alzheimer's disease (AD) is a debilitating form of dementia which leads to impaired memory, thinking and behavior. This work examines elemental concentrations between "normal" and AD subjects as well as the hemispherical differences within the brain. Tissue samples from both hemispheres of the frontal lobe in both AD and normal subjects were examined for their trace element concentrations using PIXE and RBS analyses. Elemental concentrations were seen to differ between AD and normal brain tissue samples. While in the normal group concentrations were found to be significantly higher in the right hemisphere than in the left the converse was true in AD. A change in elemental concentrations may indicate possible alterations in the function of the blood brain barrier. This was examined by determining regional cerebral metabolic rates of glucose (rCMRGlu) using the in vivo technique of positron emission tomography (PET). Again variations between both hemispheres and between AD and normal were found.  相似文献   

19.
Hairless rats, clothes, human hair, filter paper and water were exposed to gaseous elemental iodine in a glass chamber for 60–120 minutes. The deposition of gaseous elemental iodine on skin and lung of rats, human hair, water, clothes and paper were investigated by measuring iodine content in the exposed material by epithermal neutron activation analysis (ENAA). For measurement of the iodine concentration in the chamber air, elemental iodine in the air was collected by continuously sucking air through an active charcoal column. The trapped iodine in the active charcoal was then determined by ENAA. The measured deposition velocity in the test chamber of gaseous elemental iodine on skin, clothing, hair and water ranges from 0.006 on filter paper and water to about 0.05 cm/s on skin and clothes. The variation of elemental iodine concentration in air of the glass chamber was investigated by collecting and analyzing air samples at various time intervals. The results show that the variation with time in the concentration of the iodine can be described by an exponential function.  相似文献   

20.
Hair analysis receives a large amount of academic and commercial interest for wide-ranging applications. However, in many instances, especially for elemental or 'mineral' analysis, the degree of success of analytical interpretation has been quite minimal with respect to the extent of such endeavors. In this critical review we address the questions surrounding hair analysis with specific intent of discovering what hair concentrations can actually relate to in a biogenic sense. This is done from a chemistry perspective to explain why and how elements are incorporated into hair and their meaning. This includes an overview of variables attributed to altering hair concentrations, such as age, gender, melanin content, and other less reported factors. Hair elemental concentrations are reviewed with regard to morbidity, with specific examples of disease related effects summarized. The application of hair analysis for epidemiology and etiology studies is enforced. A section is dedicated specifically to the area of population studies with regards to mercury, which highlights how endogenous and exogenous incorporation relies on species dependant metabolism and metabolic products. Many of the considerations are relevant to other areas of interest in hair analysis, such as for drug and isotopic analysis. Inclusion of a table of elemental concentrations in hair should act as a valuable reference (298 references).  相似文献   

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