Element Concentrations In Hair Research Articles

Элементный статус населения как индикатор экологического загрязнения

As it is known from numerous scientific data, human health is mainly influenced by the environment and food. As is known, the concentration of chemical elements in hair reflects the ecological state of the territory, which is formed under the influence of natural and/or anthropotechnogenic factors. The formation of causal relationships between the environmental risk of the occurrence and development of the disease of androgenic alopecia served as the basis for the qualitative and quantitative characteristics of the factors influencing the occurrence of the disease in question on the example of residents of the Krasnoyarsk Territory. The presented analysis of correlations between the quantitative content of macro- and microelements in the environment, food and the quantitative content of elements in hair allowed us to establish many reliable links. At the same time, reliable correlations have been established to a greater extent between the content of chemical elements in hair and grain products. Whereas for trace elements contained in the soil and in the hair, a minimum value was established, which, in our opinion, is due to the fact that the gross content of the studied macro-trace elements was determined in the soil. Keywords: ENVIRONMENTAL RISK, ANDROGENIC ALOPECIA, TRACE ELEMENT STATUS, CONCENTRATION OF CHEMICAL ELEMENTS, ENVIRONMENT

Hair and cord blood element levels and their relationship with air pollution, dietary intake, gestational diabetes mellitus, and infant neurodevelopment

Exposure to a range of elements, air pollution, and specific dietary components in pregnancy has variously been associated with gestational diabetes mellitus (GDM) risk or infant neurodevelopmental problems. We measured a range of pregnancy exposures in maternal hair and/or infant cord serum and tested their relationship to GDM and infant neurodevelopment. A total of 843 pregnant women (GDM=224, Non-GDM=619) were selected from the Complex Lipids in Mothers and Babies cohort study. Forty-eight elements in hair and cord serum were quantified using inductively coupled plasma-mass spectrometry analysis. Binary logistic regression was used to estimate the associations between hair element concentrations and GDM risk, while multiple linear regression was performed to analyze the relationship between hair/cord serum elements and air pollutants, diet exposures, and Bayley Scales of infant neurodevelopment at 12 months of age. After adjusting for maternal age, BMI, and primiparity, we observed that fourteen elements in maternal hair were associated with a significantly increased risk of GDM, particularly Ta (OR=9.49, 95% CI: 6.71, 13.42), Re (OR=5.21, 95% CI: 3.84, 7.07), and Se (OR=5.37, 95% CI: 3.48, 8.28). In the adjusted linear regression model, three elements (Rb, Er, and Tm) in maternal hair and infant cord serum were negatively associated with Mental Development Index scores. For dietary exposures, elements were positively associated with noodles (Nb), sweetened beverages (Rb), poultry (Cs), oils and condiments (Ca), and other seafood (Gd). In addition, air pollutants PM2.5 (LUR) and PM10 were negatively associated with Ta and Re in maternal hair. Our findings highlight the potential influence of maternal element exposure on GDM risk and infant neurodevelopment. We identified links between levels of these elements in both maternal hair and infant cord serum related to air pollutants and dietary factors.

Mineral, trace element, and toxic metal concentration in hair from dogs with idiopathic epilepsy compared to healthy controls.

Altered trace element status is associated with epilepsy in humans and dogs with idiopathic epilepsy (IE). Compare hair element concentrations in epileptic and healthy dogs. Sixty-three dogs with IE (53 treated, 10 untreated) and 42 controls. Case-control study using ICP-MS to determine hair calcium, magnesium, phosphorus, sodium, potassium, iron, copper, manganese, zinc, selenium, chromium, lead, mercury, cadmium, arsenic, aluminum, and nickel concentration. Groups were compared using nonparametric tests. Results were controlled for diet, sex, age, and hair color using generalized linear mixed models. Compared to healthy controls, dogs with IE had lower hair phosphorus (mean ± SD; IE: 286.19 ± 69.62 μg/g, healthy: 324.52 ± 58.69 μg/g; P = .001), higher hair copper (IE: 10.97 ± 3.51 μg/g, healthy: 8.41 ± 1.27 μg/g; P < .001), zinc (IE: 158.25 ± 19.64 μg/g, healthy: 144.76 ± 32.18 μg/g; P < .001), copper/zinc ratio (IE: 0.07 ± 0.02, healthy: 0.06 ± 0.01; P = .003), selenium (IE: 1.65 ± 0.43 μg/g, healthy: 0.94 ± 0.73 μg/g; P < .001), and arsenic (IE: 0.40 ± 0.78 μg/g, healthy: 0.05 ± 0.08 μg/g; P < .001). When comparing treated and untreated epileptic dogs with healthy dogs, the differences in phosphorus and selenium remained significant for both groups, whereas the differences in copper, zinc, and arsenic were significant only for treated dogs. Potassium bromide treatment was strongly associated with high hair arsenic (P = .000). Altered trace element status could be involved in the pathophysiology of IE in dogs. Antiseizure drugs might affect trace element and arsenic metabolism.

Levels of Toxic and Essential Elements and Associated Factors in the Hair of Japanese Young Children.

There is growing concern regarding the effects of toxic element exposure on the development of children. However, little is known about the level of toxic elements exposure in Japanese children. The purpose of this study was to assess the concentrations of multiple elements (aluminum, cadmium, lead, calcium, copper, iron, magnesium, sodium, zinc) in the hair of 118 Japanese young children and to explore the factors associated with their element levels. The element concentration was analyzed by ICP-MS, and children's food and water intake were assessed by the questionnaire. Results showed that there were no large differences between the level of elements in the hair of Japanese children and those of children in other developed countries. Girls had significantly higher levels of aluminum, copper, and iron (p = 0.000, 0.014, and 0.013, respectively), and boys had a higher level of sodium (p = 0.006). The levels of calcium, iron, magnesium, and sodium in nursery school children were significantly higher than those in kindergarten children (p = 0.024, 0.001, 0.046, and 0.029, respectively). Multiple regression analyses with controlling the confounding variables showed significant negative associations of frequency of yogurt intake with aluminum and lead levels (p = 0.015 and 0.037, respectively). When the children were divided into three groups based on the frequency of yoghurt consumption, viz. L (≤once a week), M (2 or 3 times a week), and H (≥4 to 6 times a week) group, the mean aluminum concentration (µg/g) in the L, M, and H groups was 11.06, 10.13, and 6.85, while the mean lead concentration (µg/g) was 1.76, 1.70, and 0.87, respectively. Our results suggested the validity of hair element concentrations as an exposure measure of essential elements and frequent yogurt intake as a viable measure for protecting children from toxic elements. However, these findings will need to be confirmed in more detailed studies with larger sample sizes in the future.

PSXIV-8 Gender Differences and Reference Intervals of Concentrations of Chemical Elements in Hair from the Mane of the Bashkir Horses in the South Ural Biogeochemical Province

Abstract The main purpose of the study was to establish gender differences and reference intervals for the concentration of chemical elements in hair from the mane of horses bred in a biogeochemical province, the South Urals of Russia. The studies were carried out on physiologically healthy stallions and mares of the Bashkir breed (n=120; age 3-7 years). Hair samples were taken from the manes of horses. The elemental composition of samples was estimated from 13 chemical elements (Al, Cd, Co, Cr, Cu, Fe, I, Mn, Pb, Se, Sr, Zn, Si) by ICP AES and ICP MS. Reference intervals for the content of chemical elements in animal hair were calculated in accordance with the recommendations of Poulsen et al. (1997; 2.5-97.5 percentile). It was found that the concentrations of Al, Co, Fe and Pb in the hair of stallions significantly (Р≤0.05) exceeded those of mares. The content of Zn, on the contrary, was greater in stallions than in mares. Due to the fact that the elemental composition of the hair of stallions and mares was significantly different, the reference intervals were calculated for each gender group separately. For mares, these values were (mg/kg): Al (41.14-186); CD (0.0049-0.0189); Co (0.039-0.138); Cr (0.389-1.97); Cu (4.66-6.61); Fe(70.99-263); I (0.161-0.333); Mn (2.7-7.66); Pb (0.078-0.265); Se (0.129-0.292); Si (7.88-16.93); Sr (1.53-4.5); Zn(118-156); for stallions: Al (121-226); CD (0.0053-0.0125); Co (0.073-0.187); Cr (0.362-0.887); Cu (5.18-7.01); Fe (210-338); I (0.128-0.502); Mn (2.43-9.15); Pb (0.234-0.928); Se (0.168-0.356); Si (5.25-13.13); Sr (2.44-3.8); Zn (147-193). It is proposed to use the obtained values as physiological standards for assessing the elemental status of the Bashkir horses bred in the South Ural biogeochemical province.

77 Trace elements in whole blood and mane hair of horses fed varying sources and levels of trace elements

There has been interest in using hair as a marker for mineral status in horses, but there is a lack of quality research to develop a method to do so. The objectives of this study were to determine if dietary supply of minerals would affect blood and mane hair element concentrations and if there would be a relationship between blood and mane hair element concentrations. Nine mature geldings were used in a replicated 3 × 3 Latin square design. All horses had ad libitum access to forage and 3 dietary treatments were provided by a soybean meal pellet: organic trace minerals (ORG), inorganic trace minerals (ING), and no added trace minerals (CON). The ING and ORG pellet provided the same amount of Co, Cu, Mn, Se, and Zn (between 100 and 380% of NRC requirements), but varied in source and CON provided levels of minerals between 15 and 170% of NRC requirements depending on the mineral. There were 3 21-d treatment periods, including a 5-d washout, so each horse received each treatment. Before the first period, a 3 to 4 cm section of mane hair at the poll was clipped close to the skin. On the last day of each treatment period, blood and mane hair were collected. Mane hair was clipped from the same poll area so only new hair growth was collected. Hair and blood were analyzed for Co, Cr, Cu, Mn, Se, Pb, and Zn using ICP-MS. Data were analyzed using ANOVA with treatment, period, and square replicate as effects. The effect of mane hair color on mineral concentration was evaluated using an ANOVA with hair color as the main effect (black, n = 5; chestnut, n = 3; 1 gray, not included). Means were separated using LSD test. Correlations between hair and blood elements were made using Pearson correlation coefficients. Blood Co tended to be lowest in CON compared with other treatments (P = 0.071). Blood Cr tended to be greatest (P = 0.107) and blood Se was greatest (P < 0.05) in ORG compared with CON, with ING not different from either group. Hair Co was greatest in ORG compared with ING, but CON was not different from either (P < 0.05). Hair Cr tended to be greatest in CON compared with ING, with ORG not different from either (P = 0.102). Hair Pb was greatest in CON compared with the other treatments (P < 0.05). The only correlation between blood and hair was a weak trend for blood Co to be correlated with hair Co (r = 0.347; P = 0.076). Across all treatments, black hair had greater concentrations of Se and lower concentrations of Zn than chestnut hair (P < 0.05). While this study did not find correlations between hair and blood, mineral level and source did alter blood and hair concentrations of certain elements independently, and hair color influences mineral deposition.

Toward ‘element balance’ in ADHD: an exploratory case control study employing hair analysis

ABSTRACT Background: Head hair analysis has been used for decades to clarify mineral relationships to symptoms of ADHD, but there is little consensus among findings. We sought to explore 33 hair element concentrations and their 528 calculated ratios among two groups of boys, one with ADHD and one without. Method: 107 boys aged 7–12 years were recruited; 55 with ADHD and 52 non-ADHD Controls. Hair minerals were compared using Mann–Whitney U tests, p<0.01 was used for significance. Dietary data were obtained using a 138 item food frequency questionnaire (FFQ). Results: There were three group differences on individual elements: bismuth/Bi: 8 fold higher in ADHD, chromium/Cr: 15% lower in ADHD and germanium/Ge: 11% lower in ADHD, Cr level being the strongest predictor of ADHD symptoms. We found thirty significant group differences in element ratios, two thirds involving Bi and eight of these showing that as ADHD severity increased, the ratios with Bi as the denominator decreased (r ranging from −0.263 to −0.433, p<0.01). From the FFQ, tinned fruit was consumed more often in the ADHD group. Hair arsenic levels were somewhat elevated across both ADHD and Control groups. Discussion: While element ‘imbalance’ appears to be associated with ADHD, we did not replicate any previous study results of group differences on individual elements. We have raised the possibility that the ratios may be far more important than any one individual element in better elucidating the effects that minerals may have on the pathogenesis of ADHD. These are cautionary findings requiring replication.

Concentration of Zinc, Copper, Selenium, Manganese, and Cu/Zn Ratio in Hair of Children and Adolescents with Myopia

The aim of this work was to determine the concentration of trace elements, zinc, copper, selenium, manganese, and Cu/Zn ratio, in scalp hair samples of children and adolescents with myopia. The study included 92 children (mean age 14.5 ± 2.5 years) with myopia and 43 healthy persons (mean age 11.8 ± 4.7 years). Each patient had a complete eye examination. Trace element concentrations in hair were determined by atomic absorption spectrometry. Cu/Zn ratio was also calculated. The zinc level in the hair of myopic patients was significantly higher (260 µg/g) in comparison to the control group (130 µg/g). There was a significantly lower Cu/Zn ratio in myopic patients (0.045) compared with controls (0.07). An insignificant difference was observed in the hair level of copper, selenium, and manganese between patients and controls. The results show that trace elements may play a significant role in the pathogenesis of myopia. Further studies should pay more attention to determine the effect of trace element on children myopia.

The Association between Mineral and Trace Element Concentrations in Hair and the 10-Year Risk of Atherosclerotic Cardiovascular Disease in Healthy Community-Dwelling Elderly Individuals.

This cross-sectional analysis included 137 Korean subjects aged 60–79 years. All subjects underwent anthropometric measurements and laboratory tests. Scalp hair samples were obtained from each individual, the concentrations of 36 minerals and trace elements were analyzed, and 16 ratios of elements were calculated. ASCVD risk was estimated using pooled cohort ASCVD risk assessment equations for 10-year risk profiles. The 137 subjects were divided into three risk groups: low (<5%, n = 28), intermediate (5% to <7.5%, n = 21), and high (≥7.5%, n = 88) risk groups. After adjusting for obesity (BMI ≥ 25 kg/m2) and sex, Na concentration (mg%) in hair was significantly lower in the low-risk (13.91 ± 7.02) than in the intermediate-risk (47.18 ± 8.08) and high-risk (36.76 ± 3.95) groups (p for trend = 0.024). The concentration of K (mg%) in hair was also positively associated with the severity of ASCVD risk (10.50 ± 8.37, 23.62 ± 9.63, 33.31 ± 4.71, respectively; p for trend = 0.017), but their differences were not statistically significant (p = 0.059). By contrast, the levels of Co, U, and Hg, and the Ca/P and Ca/Mg ratios, were negatively correlated with the severity of ASCVD risk (p for trend < 0.05). Mean Na concentration in hair was significantly lower in the low-risk than in the other risk groups. By contrast, Co, U, and Hg concentrations showed significant negative associations with risk severity. Further studies are needed to assess whether dietary modification for trace elements could lower the risk of ASCVD.

Biomonitoring and health risks assessment of trace elements in various age- and gender-groups exposed to road dust in habitable urban-industrial areas of Hefei, China

The current study investigates the concentration of eleven trace elements in biomaterials including hair (85) and nails (85) along with seventy five (75) road dust samples collected from a healthy population of habitable urban-industrial areas of Hefei, China. The samples were acid digested and analyzed using ICP-MS for trace elements content. The mean concentration of Elements followed descending order of Zn > Mg > Fe > Cr > Al > Sn > Sr > Ti > Cu > As > Cd and Mg > Zn > Fe > Cr > Al > Sn > Ti > Cu > Sr > As > Cd in hair and nails, respectively. Overall, the concentration of elements was found to be high in female subject as compared to male. The concentration of trace elements in hair and nail exceeded the maximum permissible limits in most cases. The corresponding mean values from dust samples were fairly high as compared to background values of trace elements. Middle age groups (21–30 years and 31–40 years) were observed to be the most vulnerable there-by posing a high health risk, as the concentration of trace elements was significantly high in these groups except for Al, which was detected high in age < 20 in case of both male and female. A significantly high correlation was found between trace elements in biomaterials and those detected in dust samples. In hair samples, a significantly positive correlation was noticed for As with Mg, Zn, Sn and Fe, Sn/Mg and Mg/Ti. In the case of nails, a significant correlation was observed for elements like Al, Mg, Zn, Cr, and Cu. The Cluster and principal component analysis revealed industrial and vehicular emissions as main sources for trace elements exposure in humans.

ИЗБЫТОЧНАЯ КОНЦЕНТРАЦИЯ МАРГАНЦА В ПИТЬЕВОЙ ВОДЕ И РИСК ДЛЯ ЗДОРОВЬЯ НАСЕЛЕНИЯ СЕВЕРНОГО РЕГИОНА

An analysis of the concentration of Mn in drinking water samples collected 425 of the Khanty-Mansiysk autonomous region: 228 from localities with high-quality drinking water purification and 198-with poor quality. Overstepping the MPC in most water samples with poor-quality clean it up. Content of Mn in investigated hair 468 adult residents of Khanty-Mansiysk autonomous region. Overstepping the average values of the element concentrations in hair of all those surveyed, significantly (p = 0.005) higher among residents of settlements with poor-quality drinking water purification. Excessive accumulation of Mn in human body, along with other factors, can potentiate the development of disease pathogenesis based on oxidative stress (primarily, cardiovascular), as well as thyroid disease, musculoskeletal system, iron deficiency anemia, etc.

Major Limitations in Using Element Concentrations in Hair as Biomarkers of Exposure to Toxic and Essential Trace Elements in Children.

Background:Hair is a commonly used exposure biomarker for metals and other trace elements, but concern has been raised regarding its appropriateness for assessing the internal dose.Objectives:The aim of the present study was to evaluate children’s hair as biomarker of internal dose for toxic (As, Mn, Cd, Pb) and essential elements (Mg, Ca, Fe, Co, Cu, Zn, Se, Mo).Methods:In 207 children (9–10 years of age), originating from a population-based cohort in rural Bangladesh, we measured concentrations of the selected elements in hair ( closest to the scalp) using ICP-MS. We compared these with previously measured concentrations in erythrocytes, urine, and water. For a subset of children (), we analyzed four consecutive pieces of hair.Results:There were strong associations between hair As and the other biomarkers (erythrocytes: , ; urine: , ); and water (, ); and there were significant correlations between Se in hair and erythrocytes (overall , ), and urine (, ). Hair Co and Mo showed weak correlations with concentrations in erythrocytes. Hair Mn was not associated with Mn in erythrocytes, urine, or water, and the geometric mean concentration increased almost five times from the closest to the head to the (). Also Mg, Ca, Co, Cd, and Pb increased from the scalp outward ( higher in compared with , ).Conclusions:Hair was found to be a useful exposure biomarker of absorbed As and Se only. Of all measured elements, hair Mn seemed the least reflective of internal dose. https://doi.org/10.1289/EHP1239

Trace elements in scalp hair from potentially exposed individuals in the vicinity of the Bayan Obo mine in Baotou, China.

Mining activities including mineral excavation and ore transportation produce and release large amounts of pollutants to the surrounding environment, raising concerns regarding the effects of environmental exposure to pollutants on human health. The concentration of elements in hair can be used as a biomarker of exposure to chemical elements. In the present study, hair samples from 89 relatively healthy volunteers aged 11-77 years old (57 living near Bayan Obo giant REE-Nb-Fe ore deposit and 32 in non-mining areas) from Baotou (Inner Mongolia, China) were analyzed to determine the contents of 25 chemical elements (Ag, Al, As, Ba, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Li, Mg, Mn, Mo, Ni, Pb, Rb, Se, Tl, U, V and Zn) with the aim of gaining insights about the potential exposure to chemical elements of the population living within the Bayan Obo opencast mining area. The effects of gender and living area on element concentrations in hair were also investigated. The results showed that the mean concentrations of the target elements (Ag, Al, Ba, Cd, Co, Li, Mn, Ni, Pb, Tl, V, Cs, Ga, Rb, U, Bi, Mo, As, Ca, Fe, Mg and Zn) in human hair from the mining area (MA) were primarily higher than that in non-mining areas (NMA). The area of residence had an influence on the presence of select trace elements (As, Cd, Mg, Pb, Tl, U and Zn) in human hair. In addition, the hair samples from MA showed statistically significant differences between males and females for a larger number of elements than those in NMA in which only Ag, Bi and Se were significantly different. This result implies a potential influence of mining activities on residents living in the vicinity. These findings confirm the need for competent authorities to act as early as possible and to implement strategies aimed to protect exposed populations and the entire ecosystem.

Hair elements and healthy aging: a cross-sectional study in Hainan Island, China.

Healthy aging is considered as the core issue of aging population. Centenarians are a symbol of healthy aging. Concentration of elements in hair is an indicator of micronutrient status, which can affect the human health. In the present study, we investigated element concentrations in the scalp hair of 255 healthy centenarians from Hainan Island, China. The pattern of intergenerational transmission of elements and the effects of confounders such as sex, age, education level, smoking habits, alcohol intake, and frequency of hospitalization on hair element concentrations were assessed. For most elements, the load in hair increased significantly through intergenerational transmission (i.e., centenarians<children<grandchildren). Our results also demonstrated that female centenarians had significantly higher concentrations of Ca, Mg, Mn, Se, and Sr but lower levels of Cr and P. The Mn level was statistically significantly lower in the primary studies group. Alcohol intake was positively associated with Cd and Na levels, whereas smoking habits showed no significant effect on all the elements. Furthermore, the frequency of hospitalization was significantly positively associated with Cd, Cu, and Pb concentration. Moreover, our analysis suggested that adequate concentrations of Fe and Se might increase the life span of centenarians, whereas excessive concentrations of P and Pb were harmful to health and reduced life span. These results imply that element concentrations could be manipulated as a therapeutic modality in geriatric disease. They might also provide reference values for diseased subjects, allowing improved diagnoses and more effective therapies, which might support effective policies on health and aging.

Essential metals profile of the hair and nails of patients with laryngeal cancer

Trace elements have an impact on numerous physiological processes. The monitoring of their levels in the organism allows you to detect not only their deficiencies, but also several illnesses. The aim of this study was to compare the levels of essential elements (calcium, magnesium, zinc, copper, iron, manganese) in hair, nails and serum of both patients with laryngeal cancer and healthy people. The determination of six metals was performed by an inductively coupled plasma mass spectrometry (ICP-MS) and an inductively coupled plasma optical emission spectrometry (ICP-OES). The concentration of essential elements in hair and nails of the control group was statistically significantly higher than in the group of patients with laryngeal cancer. In the case of serum, differences were found between the patients and controls in respect of the level of three metals. The results of principal component analysis (PCA) revealed the strong and similar clustering behavior of essential elements in hair and nails. The metals did not correlate between two alternative materials. The present study indicated that, using the level of essential elements in hair and nails as a basis, it is possible to distinguish cancer patients from healthy people. The alternative materials are independent of homeostasis and therefore seem to be more useful in the detection of diseases and mineral deficiencies in human than the classical biological materials, such as blood.

A trace element analysis of hair in stroke with comorbid depression and cognitive impairment

To identify changes in the concentration of trace elements in hair of post stroke patients with comorbid depression and cognitive impairment. Authors examined macro - and trace element hair composition of 63 stroke patients with comorbid depressive and cognitive disorders. The quantity determination was performed by atomic emission spectroscopy. An increase in hair concentrations of conditionally toxic elements Cd and Pb, essential trace elements Cu, Fe, Mn and decrease in concentrations of Zn were found in the patients with comorbid depression compared to reference values. Post stroke patients with comorbid depression and cognitive impairment had disturbances of the metabolism of trace elements involved in the intrinsic systems of homeostasis.

Element profiles in hair and nails of children reflect the uptake from food and the environment

The present study evaluated if the element profiles in hair and nails of children from the Lake Victoria region in Kenya reflect uptake from food and the environment. To this purpose, the element concentrations in hair and nails were related to element concentrations measured in food items, water, and soil. The highest intake of most elements occurred via ingestion of the fish Rastrineobola argentea, which is consumed in higher quantities than other fish and food items. Element concentrations in hair and nails were correlated to food and soil in element-specific patterns. Multivariate analysis combining principal component analysis and multidimensional scaling enabled us to cluster individuals from specific sites and to relate differences between sites to food-consumption patterns and environmental exposures. Site-specific differences in macroelement concentrations among the children were attributed to patterns of food consumption, while those in microelement concentrations reflected differences in geochemical background. It is concluded that the simultaneous analysis of elements in human hair and nails allows separation of populations based on food consumption and geochemical background.

Trace element indices in hair and saliva of school children

Evaluation of essential trace elements in hair and saliva is gradually being accepted as a useful tool in both scientific research and the diagnoses of disease. The normal concentration of these trace elements in hair and saliva; iron, zinc, copper, manganese were determined in 265 healthy children (7-9y). The concentration of these trace elements in hair and saliva were in (Hair: Fe 28.47±0.70mg/kg; Zn 172.08±4.49mg/kg; Cu 21.03±0.79kg; Mn 1.30±0.05kg and Saliva: Fe 1.06±0.03mg; Zn 0.64±0.39mg; Cu 0.19±0.09mg; Mn 0.11±0.00 nmol/L). There was a significant high levels of trace element in hair but reduced concentration in saliva samples when compared with the reference means (P<0.05 in each case). There is correlation between Zn concentration in saliva and Zn concentration in hair (P<0.05). There is also a relatively low level of Mn in saliva compared with the proportion that meets the thresholds (0.11±0.003nmol/l) in the children. In comparing samples levels with some other parameters there is no significant correlation between them, also the anthropometric data and socioeconomic status of children had no effect on the levels of these elements in hair and saliva. The results indicate the possibility of assessing the presence of these elements using non-invasive methods in the absence of contamination and thus substantiate the potential of hair and saliva as a biomarker but could not ascertain the exact tolerable levels of the elements in children.

Identification of Human Age Using Trace Element Concentrations in Hair and the Support Vector Machine Method

Trace element content in hair is affected by the age of the donor. Hair samples of subjects from four counties in China where people are known to have long lifespan ("longevity counties") were collected and the trace element content determined. Samples were subdivided into three age groups based on the age of the donors from whom these were taken: children (0-15years); elderly (80-99years); and centenarians (≥100years). We compared the trace element content in hair of different age groups of subjects. Support vector machine classification results showed that a non-linear polynomial kernel function could be used to classify the three age groups of people. Age did not have a significant effect on the content of Ca and Cd in human hair. The content of Li, Mg, Mn, Zn, Cr, Cu, and Ni in human hair changed significantly with age. The magnitude of the age effect on trace element content in hair was in the order Cu > Zn > Ni > Mg > Mn > Cr > Li. Cu content in hair decreased significantly with increasing age. The hair of centenarians had higher levels of Li and Mn, and lower levels of Cr, Cu, and Ni comparing with that of the children and elderly subjects. This could be a beneficial factor of their long lifespan.

Trace element concentrations in hair of healthy Chinese centenarians

Trace element concentrations, as indicators of micronutrient status of healthy centenarians, have not been widely analyzed. This study aimed to assess trace element concentrations in the hair of healthy centenarians. The effects of gender and age on element concentrations were also investigated. Eleven trace elements (Al, Ba, Cd, Cr, Cu, Fe, Mo, Pb, Se, Sr and Zn) in the scalp hair of 107 healthy Chinese centenarians were examined. The overall reference values (RVs) in mg/kg for the hair concentrations of trace elements in centenarians were as follows: Al, 14.95; Ba, 2.68; Cd, 0.06; Cr, 0.59; Cu, 6.21); Fe, 19.37; Mo, 0.50; Pb, 4.64; Se, 0.37; Sr, 4.84; and Zn, 154.37. Data analysis found that only Cu and Zn concentrations show a normal distribution, and there is no significant difference between males and females in any element except Zn. However, the levels of Al, Cd, Cr, Fe, Mo, Pb decrease and the levels of Ba, Cu, Se, Sr, Zn increase with age in the centenarian cohort. Results also revealed that sufficient Zn and Se concentrations as well as low exposure to heavy metals pollution contribute to the longevity of centenarians. The results imply the possibility of manipulating trace element concentrations, especially Zn and Se concentrations in tissues, as a means for therapeutic modality in geriatric disease.