Evaluation of status of trace and toxic metals in biological samples (scalp hair, blood, and urine) of normal and anemic children of two age groups

Micronutrients and socio-demographic factors were major predictors of anaemia among the Ethiopian population

Anaemia is characterised by low hemoglobin (Hb) concentration. Despite being a public health concern in Ethiopia, the role of micronutrients and non-nutritional factors as a determinant of Hb concentrations has been inadequately explored. This study focused on the assessment of serum micronutrient and Hb concentrations and a range of non-nutritional factors, to evaluate their associations with the risk of anaemia among the Ethiopian population (n 2046). It also explored the mediation effect of Zn on the relation between se and Hb. Bivariate and multivariate regression analyses were performed to identify the relationship between serum micronutrients concentration, inflammation biomarkers, nutritional status, presence of parasitic infection and socio-demographic factors with Hb concentration (n 2046). Sobel-Goodman test was applied to investigate the mediation of Zn on relations between serum se and Hb. In total, 18·6 % of participants were anaemic, 5·8 % had iron deficiency (ID), 2·6 % had ID anaemia and 0·6 % had tissue ID. Younger age, household head illiteracy and low serum concentrations of ferritin, Co, Cu and folate were associated with anaemia. Serum se had an indirect effect that was mediated by Zn, with a significant effect of se on Zn (P < 0·001) and Zn on Hb (P < 0·001). The findings of this study suggest the need for designing a multi-sectorial intervention to address anaemia based on demographic group.

Quantification of 26 metals in human urine samples using ICP-MSMS in a random sample collective of an occupational and environmental health care center in Aachen, Germany

Despite several studies on metal exposure in the general population, the knowledge on the background burden of distinct metals is still sparse (e.g. Cu, In, Mn, Pb, Sn, Sr, Ta, Te). While up to date reference values exist for 16 distinct metals as Biological Reference Value (BAR) or the 95th percentile for Al, As, Ba, Be, Cd, Co, Cr, Hg, Li, Mo, Ni, Pt, Sb, Se, Tl and U respectively, the background burden of the general population for the remaining elements is unknown or yet no matter of scientific counselling. We established and validated an inductively coupled plasma triple quadrupole mass spectrometry (ICP-MSMS) human biomonitoring method (HBM), that enabled us to determine 26 metals in urine. Al, As, Ba, Be, Cd, Co, Cu, Ga, Gd, Hg, In, Li, Mo, Ni, Pb, Sb, Se, Sn, Sr, Ta, Te, Tl, V and Zn were analyzed. The method was applied to 88 urine samples collected in the ambulance of the Institute for Occupational, Social and Environmental Medicine (IASU) Aachen, Germany. Patients from two major metal processing companies (steel and copper) and a more heterogenous group of occupational exposed and non-exposed persons were defined and distinguished. HBM data from about 88, in general occupationally unexposed persons against certain metals served as a collective representing the general population in first approximation. For these the 95th percentiles are reported. Significant differences of urinary metal concentrations of the employees of the two metal processing companies compared to the third group were observed among others for Cu, Cr, Ni, Mn and are discussed, thus demonstrating the usefulness of the method for both environmental and occupational purposes.

Correlation of endocrine disrupting chemicals with essential elements in biological samples of children (1-5 years) with different infectious diseases and impact on sustainable outdoor activities

Endocrine disrupting chemicals (EDCs) have been extensively explored due to their harmful effects on individual health and the environment by interfering with hormone activity and disrupting the endocrine system. However, their relationship with essential trace elements remains uncertain. This research aimed to investigate the possible correlation between essential trace elements and toxic metals, including cadmium (Cd), and lead (Pb) in children aged 1-5 years with various infectious diseases, including gastrointestinal disorders, typhoid fever, and pneumonia. The study was conducted on biological testing and specimen (scalp hair and whole blood) of diseased and non-diseased children of the same residential area and referent/control age-matched children from developed cities consuming domestically treated water. The media of biological samples were oxidized by an acid mixture before being analyzed by atomic absorption spectrophotometry. The accuracy and validity of the methodology were verified through accredited reference material from scalp hair and whole blood sample. The study results revealed that diseased children had lower mean values of essential trace elements (iron, copper, and zinc) in both scalp hair and blood, except for copper, which was found to be higher in blood samples of diseased children. This implies that the deficiency of essential residue and trace elements in children from rural areas who consume groundwater is linked to various infectious diseases. The study highlights the need for more human biomonitoring of EDCs to better comprehend their non-classical toxic properties and their concealed costs on human health. The findings suggest that exposure to EDCs could be associated with unfavorable health outcomes and emphasizes the need for future regulatory policies to minimize exposure and safeguard the health of current and forthcoming generations of children. Furthermore, the study highlights the implication of essential trace elements in maintaining good health and their potential correlation with toxic metals in the environment.

Relationships between the Content of Micro- and Macroelements in Animal Samples and Diseases of Different Etiologies

Many of the micro- and macro-elements (MMEs) required by the body are found in environmental objects in concentrations different from their original concentration that can lead to dangerous animal diseases ("microelementoses"). The aim was to study the features of MME (accumulating in wild and exotic animals) in connection with particular diseases. The work using 67 mammal species from four Russian zoological institutions was completed in 2022. Studies of 820 cleaned and defatted samples (hair, fur, etc.) after "wet-acid-ashing" on an electric stove and in a muffle furnace were performed using a Kvant-2A atomic absorption spectrometer. The content of zinc, copper, iron, cadmium, lead, and arsenic was assessed. The level of MME accumulation in the animal body contributes not only to the MME status and the development of various concomitant diseases, but the condition itself can occur by intake of a number of micronutrients and/or drugs. Particular correlations between the accumulation of Zn and skin, oncological diseases, Cu-musculoskeletal, cardiovascular diseases, Fe-oncological diseases, Pb-metabolic, nervous, oncological diseases, and Cd-cardiovascular diseases were established. Therefore, monitoring of the MME status of the organism must be carried out regularly (optimally once every 6 months).

Prevalence of childhood anemia: Potential sociodemographic and dietary factors in Nigeria

BACKGROUND

Childhood anemia is a global public health issue. In this study, we assessed the potential sociodemographic and dietary factors associated with the prevalence of anemia among children aged 6-59 months in Nigeria.

METHODS

In this cross-sectional study, we collected dietary information and demographic data on 6,338 children with anemia from the Nigerian Demographic and Health Surveys (2018). The association between the occurrence of anemia and the demographic and dietary factors was determined by conducting Chi-squared tests. Additionally, bivariate and multivariate order logit models were constructed and reported as odds ratios.

RESULTS

The results of the multivariate analysis showed that the risk of anemia was reduced by 13% and 44% in children aged 13-36 months (OR = 0.87; 95% CI = 0.77-0.98; p = 0.019) and 37-59 months (OR = 0.56; 95% CI = 0.49-0.63; p < 0.001), respectively, compared to the risk of anemia in children aged 6-12 months. Anemia was 28% less likely in children of non-anemic mothers (OR = 0.72; 95% CI = 0.66-0.80; p < 0.001) than children of anemic mothers. Children fed pumpkin, carrot, squash, and sweet potato showed a lower occurrence of anemia by 17% (OR = 0.83; 95% CI = 0.70-0.99; p = 0.036) compared to those who were not fed these vegetables. Chances of anemia increased by 14% in children who were fed white potatoes, white yams, manioc, cassava, and other root-based foods (OR = 1.14; 95% CI = 1.01-1.29; p = 0.036).

CONCLUSION

This study highlighted the impact of a plant-based diet on the high prevalence of childhood anemia in Nigeria. Therefore, reformation of dietary habits, the inclusion of nutritional supplements, and food-fortification programs with reductions in maternal anemia are recommended.

The price of persistence: Assessing the drivers and health implications of metal levels in indicator carnivores inhabiting an agriculturally fragmented landscape

Patterns and practices of agricultural expansion threaten the persistence of global biodiversity. Wildlife species surviving large-scale land use changes can be exposed to a suite of contaminants that may deleteriously impact their health. There is a paucity of data concerning the ecotoxicological impacts associated with the global palm oil (Elaeis guineensis) industry. We sampled wild Malay civets (Viverra tangalunga) across a patchwork landscape degraded by oil palm agriculture in Sabah, Malaysian Borneo. Using a non-lethal methodology, we quantified the levels of 13 essential and non-essential metals within the hair of this adaptable small carnivore. We robustly assessed the biological and environmental drivers of intrapopulation variation in measured levels. Metal concentrations were associated with civet age, weight, proximity to a tributary, and access to oxbow lakes. In a targeted case study, the hair metal profiles of 16 GPS-collared male civets with differing space use patterns were contrasted. Civets that entered oil palm plantations expressed elevated aluminium, cadmium, and lead, and lower mercury hair concentrations compared to civets that remained exclusively within the forest. Finally, we paired hair metal concentrations with 34 blood-based health markers to evaluate the possible sub-lethal physiological effects associated with varied hair metal levels. Our multi-facetted approach establishes these adaptable carnivores as indicator species within an extensively altered ecosystem, and provides critical and timely evidence for future studies.

Effect of nickel on red blood cell parameters and on serum vitamin B12, folate and homocysteine concentrations during pregnancy with and without anemia

BACKGROUND

Research to date suggests that nickel affects not only the metabolism of vitamin B12 but also folates and thus may affect hematopoiesis processes.

OBJECTIVE

The aim of the study was to examine the relationship of nickel (Ni) status to red blood cell (RBC) parameters and serum vitamin B12, folate and homocysteine concentrations in the course of normal pregnancy and in pregnant women with anemia.

METHODS

The study included fifty-three pregnant women recruited to the study from the Lower Silesia region of Poland, 17 % of whom developed anemia. Nickel concentration was determined in urine, whole blood and food samples by atomic absorption spectrometry. At the same time as the food and urine samples were taken, blood was also collected for the determination of RBC parameters and serum vitamin B12, homocysteine and folate concentrations.

RESULTS

The median reported Ni intake, and the urinary and whole blood nickel contents for the studied pregnant women for the first trimester were respectively - 162.46 μg/day, 3.98 μg/L and 3.32 μg/L; for the second trimester - 110.48 μg/day, 6.86 μg/L and 1.04 μg/L; and for the third trimester - 132.20 μg/day, 3.41 μg/L and 0.70 μg/L. With regard to Ni concentration in whole blood (p = 0.0204) and in urine (p = 0.0003), the differences in the values for individual trimesters were statistically significant. The whole blood Ni level was significantly higher (9.28 vs 3.62 μg/L, p = 0.0114), while the concentration of homosysteine was significantly lower (4.09 vs 5.04 μmol/L, p = 0.0165) in pregnant women with anemia compared to those without anemia. The whole blood Ni concentration was negatively correlated with almost all RBC parameters in non-anemic pregnant women.

CONCLUSIONS

Ni status changes with the development of normal pregnancy, and in the case of anemia, an increase in Ni concentration in whole blood is observed. The demonstrated correlations between the Ni status in pregnant women and RBC parameters as well as serum vitamin B12 and folate concentrations suggest that nickel is associated with the methionine-folate cycle, iron homeostasis and bacterial synthesis of vitamin B12 in humans.

RELATIONSHIP BETWEEN LEAD AND CADMIUM LEVELS IN BLOOD AND REFRACTORY CHRONIC CONSTIPATION AMONG IRANIAN CHILDREN

BACKGROUND

There is limited research examining reasons causing refractory chronic constipation (RCC) in children. The effects of lead (Pb) and cadmium (Cd) exposures on this condition have been even less clear. However, some related factors may contribute to evaluation of blood lead levels (BLLs) and blood cadmium levels (BCLs).

OBJECTIVE

The present study aimed to examine the relationship between Pb and Cd exposures and RCC in children living in the city of Ahvaz, Khuzestan Province, in Southwestern Iran.

METHODS

This study was performed on a total number of 48 children aged 2-13 years, including 36 medically-diagnosed RCC cases and 12 controls referring to a pediatric clinic in the city of Ahvaz. Their BLLs and BCLs were then determined using a graphite furnace atomic absorption spectrophotometer. The data from the researcher-designed questionnaire were also recoded and the related risk factors were analyzed through Spearman's correlation and logistic regression analysis.

RESULTS

The findings revealed that the geometric means of Pb and Cd in blood samples in the control group were 58.95 µg/dL and 0.45 µg/dL; respectively. These values in the case group were equally 45.26 µg/dL and 0.26 µg/dL; respectively. A significant difference was additionally observed between BCLs in the case and control groups (P<0.01). All children in both groups also had BLLs greater than the permissible limit endorsed by the World Health Organization (WHO) (≤10 µg/dL). On the other hand, 8.3% of the individuals in the case group and 33.3% of those in the control group had BCLs higher than the acceptable range mentioned by WHO (≤0.5 µg/dL).

CONCLUSION

Pb and Cd exposures due to environmental pollution and susceptibility to heavy metals may not be associated with RCC in children living in the city of Ahvaz. Although this research was the first one providing data on BLLs and BCLs in children with RCC, the findings could be useful for designing future epidemiologic studies.

Nickel Content in Human Internal Organs

With the growing interest in new applications of metals in modern technologies, an increase in their concentration in the environment can be observed, which, in consequence, may constitute a hazard to human health. That is why it is of a great importance to establish "reference" levels of particular elements (essential or toxic) in human biological samples.The aim of this paper was to determine nickel in autopsy tissues of non-occupationally exposed subjects in Southern Poland (n = 60). Measurements were performed by means of electrothermal atomic absorption spectrometry after microwave-assisted acid digestion according to previously optimized and validated procedure. The results obtained indicate that data cover the wide range of concentrations and generally are consistent with other published findings. Nickel levels in the brain, stomach, liver, kidneys, lungs and heart (wet weight) were between 2.15-79.4 ng/g, 0.5-44.2 ng/g,7.85-519 ng/g, 12.8-725 ng/g, 8.47-333 ng/g and 2.3-97.7 ng/g, respectively. Females had generally lower levels of nickel in tissues than males (statistically significant relationships were found for the liver, kidneys and lungs), and median nickel concentrations in all studied material within all age groups had very similar values, with the exception of stomach.

Levels of major and trace metals in the scalp hair of Crohn's disease patients: correlations among transition metals

Concentrations of 16 metals in the scalp hair of male Crohn's disease (CD) patients (n = 28) were compared to those of male control subjects (n = 25). The majority of patients (n = 20) took an anti-inflammatory agent (mesalazine), and several patients underwent colectomy. A low concentration of serum ferritin was observed in approximately 50% of CD patients due to Fe-deficiency anemia. The concentrations of Fe, Cr, and Co in the hair of CD patients were significantly higher than those of control subjects, and particularly high concentrations were found in CD patients with low serum ferritin. Significant correlations were found among the concentrations of Fe, Cr, and Co in the hair of CD patients, but not in control subjects. In agreement with previous reports, a significant negative correlation was found between ferritin and transferrin concentrations in serum, although the available data in this study was limited (n = 8). Transferrin not only binds to Fe³⁺ but also to Cr³⁺ and Co³⁺, and the amount of transferrin is increased in Fe-deficiency anemia. Thus, the majority of the Fe³⁺, Cr³⁺, and Co³⁺ in the serum of CD patients is likely to bind to transferrin, which may be associated with the higher concentrations of those metals, as well as the significant correlations among those metals in the scalp hair of CD patients. In addition, colectomy may alter the intestinal absorption rate of some metals, while mesalazine may increase the concentrations of Mn and some metals in the scalp hair by chelate formation.

Adverse Impact of Heavy Metals on Bone Cells and Bone Metabolism Dependently and Independently through Anemia

Mounting evidence is revealing that heavy metals can incur disordered bone homeostasis, leading to the development of degenerative bone diseases, including osteoporosis, osteoarthritis, degenerative disk disease, and osteomalacia. Meanwhile, heavy metal-induced anemia has been found to be intertwined with degenerative bone diseases. However, the relationship and interplay among these adverse outcomes remain elusive. Thus, it is of importance to shed light on the modes of action (MOAs) and adverse outcome pathways (AOPs) responsible for degenerative bone diseases and anemia under exposure to heavy metals. In the current Review, the epidemiological and experimental findings are recapitulated to interrogate the contributions of heavy metals to degenerative bone disease development which may be attributable dependently and independently to anemia. A few likely mechanisms are postulated for anemia-independent degenerative bone diseases, including dysregulated osteogenesis and osteoblastogenesis, imbalanced bone formation and resorption, and disturbed homeostasis of essential trace elements. By contrast, remodeled bone microarchitecture, inhibited erythropoietin production, and disordered iron homeostasis are speculated to account for anemia-associated degenerative bone disorders upon heavy metal exposure. Together, this Review aims to elaborate available literature to fill in the knowledge gaps in understanding the detrimental effects of heavy metals on bone cells and bone homeostasis through different perspectives.

Disruption of essential metal homeostasis in the brain by cadmium and high-fat diet

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Whole-life exposure to cadmium leads to elevated metal levels in the brain that further increases in high-fat diet fed mice.

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Female animals accumulate more cadmium in the brain than males, under all treatment conditions.

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Cadmium exposure is associated with changes in the levels of several essential metals.

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Cadmium and high fat diet increase levels of superoxide anion in the cortex, amygdala and hippocampus.

Analyses of human cohort data support the roles of cadmium and obesity in the development of several neurocognitive disorders. To explore the effects of cadmium exposure in the brain, mice were subjected to whole life oral cadmium exposure. There were significant increases in cadmium levels with female animals accumulating more metal than males (p < 0.001). Both genders fed a high fat diet showed significant increases in cadmium levels compared to low fat diet fed mice (p < 0.001). Cadmium and high fat diet significantly affected the levels of several essential metals, including magnesium, potassium, chromium, iron, cobalt, copper, zinc and selenium. Additionally, these treatments resulted in increased superoxide levels within the cortex, amygdala and hippocampus. These findings support a model where cadmium and high fat diet affect the levels of redox-active, essential metal homeostasis. This phenomenon may contribute to the underlying mechanism(s) responsible for the development of neurocognitive disorders.

Assessment of Hair Zinc in the School Children in Kayseri, Turkey

Zinc is an essential micronutrient for the organism and is critical for the functional and structural integrity of cells. Determination of the amount of trace element concentrations in tissues such as hair samples have been used for the evaluation of the metabolic status especially in children. Unlike serum zinc, concentrations of zinc in hair are more stable and indicative of variations over time. The purpose of this study is to assess the zinc status of healthy school-age children in Kayseri (Turkey) by measuring the zinc level in hair samples and its association with BMI and the frequency of intake of zinc-rich foods. A total of 527 healthy children, including preadolescent (n = 360) aged 6-10 years and adolescent (n = 167) aged 11-15 years were included in this study. Hair samples were analyzed for zinc content by the inductively coupled plasma-mass spectrophotometry. Analysis of 527 healthy children showed that the mean hair zinc level was 186 ± 77 μg/g. Mean hair zinc level was lower in preadolescent age group than adolescents. There was no significant relationship between the monthly income of the family and the zinc-rich food intake and the zinc level of the hair. Our study shows that samples for analysis of zinc can be obtained with a noninvasive method for determining cases of deficiency during periods of rapid growth. However, further studies are needed to determine the normal tissue zinc level in healthy children, especially in our country and including different geographical regions.

Human Biomonitoring of Trace Elements in Scalp Hair from Healthy Population of Pakistan

The present study deals with the assessment of essential trace and toxic elements in biological samples (scalp hair) of healthy smoker and non-smoker residents of Lahore (the second most populous city), Pakistan. Human biomonitoring of various trace elements like zinc (Zn), iron (Fe), copper (Cu), chromium (Cr), cadmium (Cd), nickel (Ni), lead (Pb), and arsenic (As) was evaluated in human hair samples of smokers and non-smokers (males and females) as per IFCC criteria. For the purpose of comparison, scalp hair samples of age- and sex-equivalent healthy persons were also analyzed. The results of this study show that the concentrations (P95 values) of As (0.17, 0.81, and 0.91 μg/g), Cd (2.80, 3.81, and 3.16 μg/g), Cr (4.1, 4.2, and 5.3 μg/g), Cu (20.0, 21.0, and 21.9 μg/g), Ni (3.9, 4.6, and 4.3 μg/g), Pb (4.0, 4.8, and 5.0 μg/g), and Fe (49.0, 49.0, and 59.3 μg/g) were significantly higher in scalp hair samples of smokers than in referents, for various age groups (16-32 years, 33-50 years, and 51-62 years), respectively. The concentrations of Zn (165, 163, and 173 μg/g various age groups, respectively) in similar age group were found lower in the scalp hair samples of smokers than referents. Exposure of high toxic metal level through smoking and deficiency of Zn could be synergistic with the risk factors associated with the use of tobacco. Correlation studies for the elements in cigarette with the elements in scalp hair of male smokers show a highly positive correlation between Cr-Cd, Cr-Ni, Cu-Fe, and Ni-Zn.

Urine metals concentrations and dyslexia among children in China

BACKGROUND

Exposures to heavy metals has been linked to many developmental disorders. However, few studies have investigated the effects of exposure and co-exposure to metals on dyslexia, especially with regard to dyslexics in China.

OBJECTIVES

To investigate the association between urine metal concentrations and dyslexia in a case-control study among children in China.

METHODS

A case-control study was conducted in the Tongji Reading Environment and Dyslexia (READ) research program. A total of 228 dyslexics and 228 controls were matched on gender, age (within one year), and grade. The concentrations of 21 urine metals were measured by an inductively coupled plasma-mass spectrometer (ICP-MS). Multivariable conditional logistic regression models were applied to estimate the adjusted odds ratios (ORs) of Chinese dyslexia.

RESULTS

After adjusting for potential confounders, two metals (selenium and argentum) were significantly associated with dyslexia in single-metal multivariable models. Argentum was positively associated with the risk of dyslexia, while selenium was negatively associated. In the multiple-metal model, compared with extreme quartiles, the ORs (95% CIs) for selenium was 0.36 (95% CI: 0.14-0.93; P_trend = 0.029). In the joint association analysis, children with higher levels of urine argentum and lower level of urine selenium had a significantly higher risk of dyslexia than those with low levels of argentum and selenium (OR = 5.06, 95% CI: 1.67-18.84).

CONCLUSIONS

The findings suggest that exposure to selenium and argentum may relate to dyslexia in China. Longitudinal studies are needed to further evaluate these relationships and investigate potential mechanisms.

Relationship between Selected Trace Elements and Hematological Parameters among Japanese Community Dwellers

This study aimed (1) to assess serum trace elements concentrations and hematological parameters, (2) to evaluate the sex differences in the associations between serum trace elements levels and hematological parameters, and (3) to identify the associations between serum trace elements concentrations and risk of anemia among Japanese community dwellers. This is a community-based cross-sectional study that utilized the data of the 2014 Iwaki Health Promotion Project. Participants were 1176 community dwellers (>18 years) residing in the Iwaki District, Aomori Prefecture, Japan. We assessed the data of serum trace elements concentrations of cadmium (Cd), cobalt (Co), copper (Cu), selenium (Se), zinc (Zn), and iron (Fe) as well as the hematological parameters of red blood cells (RBC) counts, hemoglobin, packed cells volume (PCV), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH). Serum concentrations of Zn (871.5 μg/L vs. 900.1 μg/L) and Fe (946.8 μg/L vs. 1096.1 μg/L) were significantly lower in females than in males, while serum concentrations of Co (0.4 μg/L vs. 0.3 μg/L) and Cu (1062.4 μg/L vs. 965.3 μg/L) were significantly higher in females. By multivariate linear regression, serum Se concentration was significantly, positively associated with PCV (β = 1.04; 95% confidence interval (CI): 0.17, 1.92; p = 0.016) among the study participants. Serum Zn also had positive associations with hemoglobin (β = 0.42; 95% CI: 0.07, 0.77; p = 0.020), PCV (β = 1.79; 95% CI: 0.78, 2.81; p < 0.001), and RBCs count (β = 15.56; 95% CI: 7.31, 31.69; p = 0.002). On the other hand, serum Co concentration was negatively associated with the hematological parameters, particularly in females. Moreover, serum Zn concentration had a decreased risk of anemia (lowest vs. highest quartiles: odds ratio (OR) = 0.42; 95% CI: 0.23, 0.76; p = 0.005) while higher Co concentrations had an increased risk of anemia (lowest vs. highest quartiles: OR = 1.95; 95% CI: 1.04, 3.67; p = 0.037). However, no significant association was found between serum Cu level and hematological parameters. There were substantial sex differences in serum trace elements, implying that trace elements metabolism differed between males and females. Zn can play a protective role in the development of anemia. Surprisingly, increased Co concentration increased the risk of anemia among our study population, which called for further studies to confirm and to consider for speciation analysis.

Geochemical exposure of heavy metals in environmental samples from the vicinity of old gas mining area in northern part of Sindh Pakistan. Adverse impact on children

In early nineteen century, a gas field was operational in southern part of Sindh, Pakistan for power production. The plant was completely un-operational for last three decades, whereas all wastage and raw materials are still dumped there, which might be the source to contaminate the ground water. The most of the workers population still living in different villages nearby the gas field. In present study, evaluated the undesirable effects of the toxic metals (lead and cadmium) via consuming groundwater for drinking and other domestic purpose especially in children of ≤5.0 years. For comparative purpose groundwater of nonindustrial area (nonexposed) was also analysed and their impact on age matched children was carried out. Biological samples (scalp hair and blood) were collected from children of exposed and nonexposed areas. The Cd and Pb in scalp hair and blood samples were carried out by graphite furnace atomic absorption spectrometry. Whereas, Cd and Pb in groundwater obtained from both areas were determined prior to applied preconcentration method as reported in our previous works. The Cd and Pb contents in the groundwater of villages of exposed area were found in the range of 5.18-10.9 and 19.9-69.5 μg/L, respectively. Whereas, the groundwater of nonexposed area contains Cd and Pb in the range of 1.79-3.78 and 5.07-24.3 μg/L, respectively. It was observed that the concentrations of Cd and Pb in scalp hair and blood samples of children belongs to exposed area have ≥2.0 fold higher than the resulted data attained for age matched control children, indicating as the exposure biomarkers of toxic metals. The children belong to exposed area have poor health, anemic and low body mass index (<13 kg/m2). A significant positive correlations among Cd and Pb concentrations in biological samples of exposed subjects and groundwater was observed (p < 0.01).

The Combined Effects of Cr(III) Supplementation and Iron Deficiency on the Copper and Zinc Status in Wistar Rats

The aim of the study was to assess the combined effects of chromium(III) supplementation and iron deficiency on the copper (Cu) and zinc (Zn) status in female rats. The Cr, Fe, Cu and Zn dietary and tissular levels were measured by Atomic Absorption Spectrometry (AAS) method. The data show that chromium(III) supplementation compensated for the negative effects of Fe deficiency on the Cu content but it deepened the effect on Zn levels in the female rats. Detailed data on the status of trace elements and their interactions in healthy subjects and patients with metabolic disorders (e.g. anaemia, diabetes mellitus) are strongly required for effective nutritional and therapeutic strategies.

A cross-sectional study of urinary cadmium concentrations in relation to dietary intakes in Uruguayan school children

BACKGROUND

Cadmium (Cd) exposure has adverse health effects in children. Diet contributes to Cd exposure, but dietary components could affect body Cd levels.

OBJECTIVE

To examine associations between diet and urinary Cd (U-Cd) in children.

METHODS

In this cross-sectional study conducted in Montevideo, Uruguay, Cd exposure of 5-8 year old children (n = 279 with complete data) was assessed in first morning urine (U-Cd), a marker of long-term exposure, measured by ICP-MS and adjusted for specific gravity. Distribution of U-Cd was (median [5%, 95%]: 0.06 [0.02, 0.17] μg/L); data were natural-log-transformed (ln) for statistical analyses. Serum ferritin (SF), an indicator of iron stores, was measured in fasting samples. Trained nutritionists completed two non-consecutive 24-h dietary recalls with both child and caregiver present. Measures of iron, zinc, calcium and fiber intake, and the consumption of grains, root vegetables, milk, and foods rich in heme iron (white and read meats) and non-heme iron (legumes, spinach, broccoli, tomatoes, dried fruit) were derived. Multivariable ordinary least squares (OLS) and ordinal regressions were used to examine associations among tertiles of water Cd, SF, diet, and U-Cd. OLS models were further stratified by sex.

RESULTS

In covariate-adjusted models, SF was not related to ln-U-Cd. Children in highest tertile of iron and zinc intake had lower ln-U-Cd: (-0.23 [-0.42, -0.03]) and (-0.25 [-0.44, -0.05]), respectively, compared to the reference group. Children consuming higher amounts of foods rich in heme iron had slightly lower ln-U-Cd (-0.17 [-0.36, 0.03]). High grain consumption was related to higher ln-U-Cd (0.25 [0.06, 0.45]).

CONCLUSIONS

Diets rich in grains were related to higher urinary Cd levels among children living in the context of low Cd pollution. Higher intake of iron and zinc was related to lower Cd levels. Given that urinary Cd is mainly a marker of long-term exposure, these findings should be further corroborated.

Statistical resolutions for large variabilities in hair mineral analysis

Measuring biomaterials is usually subject to error. Measurement errors are classified into either random errors or biases. Random errors can be well controlled using appropriate statistical methods. But, biases due to unknown, unobserved, or temporary causes, may lead to biased conclusions. This study describes a verification method to examine whether measurement errors are random or not and to determine efficient statistical methods.

A number of studies have dealt with associations between hair minerals and exposures such as health, dietary or environmental conditions. Most review papers, however, emphasize the necessity for validation of hair mineral measurements, since large variations can cause highly variable results. To address these issues, we answer the following questions:

How can we ascertain the reliability of measurements?

How can we assess and control the variability of measurements?

How do we efficiently determine associations between hair minerals and exposures?

How can we concisely present the reference values?

Since hair minerals all have distinctive natures, it would be unproductive to examine each mineral individually to find significant and consistent answers that apply to all minerals. To surmount this difficulty, we used one simple model for all minerals to explore quantitative answers. Hair mineral measurements of six-year-old children were analyzed based on the statistical model. The analysis verified that most of the measurements were reliable, and their inter-individual variations followed two-parameter distributions. These results allow for sophisticated study designs and efficient statistical methods to examine the effects of various kinds of exposures on hair minerals.

Chromium in Postmortem Material

Recently, considerable attention has been paid to the negative effects caused by the presence and constant increase in concentration of heavy metals in the environment, as well as to the determination of their content in human biological samples. In this paper, the concentration of chromium in samples of blood and internal organs collected at autopsy from 21 female and 39 male non-occupationally exposed subjects is presented. Elemental analysis was carried out by an electrothermal atomic absorption spectrometer after microwave-assisted acid digestion. Reference ranges of chromium in the blood, brain, stomach, liver, kidneys, lungs, and heart (wet weight) in the population of Southern Poland were found to be 0.11-16.4 ng/mL, 4.7-136 ng/g, 6.1-76.4 ng/g, 11-506 ng/g, 2.9-298 ng/g, 13-798 ng/g, and 3.6-320 ng/g, respectively.

Drinking water lead, iron and zinc concentrations as predictors of blood lead levels and urinary lead excretion in school children from Montevideo, Uruguay

The global burden of water-based lead (Pb) exposure on children is largely unknown; however, the importance of water sources as a path of Pb exposure is receiving increased attention due to recent prominent exposure events related to corroded plumbing infrastructure in the US. This study investigated the contribution of Pb in household drinking and cooking water to Pb levels in blood (PbB) and urine (PbU) within 353 early school-aged children from Montevideo, Uruguay. Additionally, the analysis considered the child's iron status and the water content of iron (WFe) and zinc (WZn) in relation to water Pb and blood/urine Pb concentrations. Lead concentrations for both PbB and PbU were fairly low (M ± SD: 4.2 ± 2.1 μg/dL; Median [5%, 95%]: 1.9 [0.6, 5.1 μg/L, respectively]); however 21% of the sample had a PbB >5 μg/dL but ≤ 10 μg/dL. Overall, there was little evidence of an association between water metal concentrations and children's PbB/PbU. However, when the sample was stratified by children's iron status, WPb was positively related to PbU, but negatively related to PbB in iron-replete children, even after adjusting for WFe and WZn. In iron-deficient children, there was no elevation in PbU with increasing WPb. In this sample of children with low Pb levels, there were no overwhelming relationships between WPb and either PbB or PbU, however, there was some evidence that iron-replete status promotes excretion of WPb.

Evaluation of the status and the relationship between essential and toxic elements in the hair of occupationally exposed workers

Lead poisoning is a common disease in lead-acid battery manufacturing industries. Workers can be also exposed to various toxic elements present as contaminants or used as catalysts to enhance batteries' performances. In the present study, levels of essential and toxic elements and their relationship were assessed by analyzing scalp hair samples of 52 workers in a Pb battery manufacturing plant. The impact of some confounding factors on hair mineral contents was also investigated. For comparative purposes, nonoccupationally exposed subjects were selected as controls. All elements were determined by triple quadrupole ICP-MS. The results indicated significantly higher levels of Pb, Sb, As, and Cd in the hair of workers when compared to controls (p < 0.01). The Spearman correlation test revealed significant correlations between Pb/Cr, Pb/Mn, Pb/Ni, Pb/As, Pb/Se, Pb/Sb, Hg/As, Hg/Sn, Hg/Sb, Sb/Cr, Sb/As, Sb/Se, Sb/Cd, Sb/Sn, Sn/Cr, Sn/As, Sn/Cd, Cd/As, Se/Ni, As/Cr, Ni/Cr, Ni/Mn, and Mn/Cr in the hair of workers and Pb/Cr, Pb/Mn, Pb/Ni, Pb/Cd, Mn/Ni, Mn/Cd, Cd/Ni, As/Ni, Sn/Ni, Sb/Sn, and Hg/Sn in the hair of controls. Multiple linear regression analysis revealed linear dependence including Cr = f(Pb, Ni, Sb), Mn = f(Ni, Sb), Ni = f(Mn, Cr, -Cd) (Cd was negatively correlated, β < 0), As = f(Sn, Sb, Hg), Se = f(Ni); Sn = f(As), Sb = f(As, Mn, -Hg, Sn, Se, -Ni) (Hg and Ni were negatively correlated), Hg = f(As, -Sb, Sn) (Sb was negatively correlated), and Pb = f(Cr). The result of this study can be very useful to explain the interactions between elements or for comparison studies when establishing reference ranges or monitoring elements in workplaces.

The Combined Effects of Iron Excess in the Diet and Chromium(III) Supplementation on the Iron and Chromium Status in Female Rats

Inadequate iron supply has significant consequences to health. There are some relations between the metabolism of different trace elements, such as iron, zinc, copper and chromium. However, the direction of these interactions can be antagonistic or synergistic, and it depends on many factors. The aim of the study was to evaluate the combined effects of supplementary of chromium(III) propionate complex (Cr3) with iron excess on the Cr and Fe status in healthy female rats. The 36 healthy female Wistar rats were divided into six experimental groups (six animals in each) with different Fe levels-adequate (45 mg kg^-1-100% RDA) and high (excessive-180 mg kg^-1-400% RDA). At the same time, they were supplemented with Cr(III) at doses of 1, 50 and 500 mg kg^-1 of diet: C1-control (Fe 45 mg kg^-1, Cr 1 mg kg^-1); C50 (Fe 45 mg kg^-1, Cr 50 mg kg^-1); C500 (Fe 45 mg kg^-1, Cr 500 mg kg^-1); H1 (Fe 180 mg kg^-1, Cr 1 mg kg^-1); H50 (Fe 180 mg kg^-1, Cr 50 mg kg^-1); H500 (Fe 180 mg kg^-1, Cr 500 mg kg^-1). The serum iron level and total iron binding capacity (TIBC) were measured with colorimetric methods. The serum ferritin level was measured by means of electrochemiluminescence immunoassay. The serum transferrin level was measured with the ELISA method. Haematological measurements were made with an automated blood analyser. The Cr and Fe tissular levels were measured with the AAS method. The exposure to a high level of Fe(III) alone or in combination with Cr caused Fe accumulation in tissues, especially in the liver and kidneys, but there were no significant changes in the TIBC, transferrin, ferritin concentration in the serum and most haematological parameters. Moreover, the serum, hepatic and renal Cr concentrations decreased. The doses of supplementary Cr(III) given separately or in combination with high level of Fe(III) disturbed the Cr content in the liver and kidneys of healthy female rats. However, they did not change most of the parameters of Fe metabolism, except the Fe kidney concentration. Supplementary Cr3 decreased the renal Fe level in groups with adequate Fe content in the diet. However, the renal Fe levels increased along with a higher Cr level in the diet in groups with high Fe content. The findings proved a relationship between Fe(III) and Cr(III) metabolism in healthy female rats. However, the direction of change varied and depended on relative amounts of these elements in the diet.

The combined effect of supplementary Cr(III) propionate complex and iron deficiency on the chromium and iron status in female rats

The aim of the study was to evaluate the combined effect of supplementary chromium(III) and iron deficiency on the chromium and iron status in female rats. The study was carried out on female Wistar rats, which were divided into 6 experimental groups with different Fe levels (deficient 10% RDA and recommended (adequate) 100% RDA). Simultaneously, for six weeks their diets were supplemented with Cr(III) at doses of 1, 50 and 500mgkg^-1. The tissular chromium and iron levels were measured with the AAS method. The serum iron and TIBC were measured with colorimetric methods The serum ferritin level was measured by means of electrochemiluminescence immunoassay. The serum transferrin level was measured with the ELISA method. The haematology was measured with an automated blood analyser. Supplementary Cr3 increased the Cr content in the tissues. This effect was weaker in the Fe-deficient groups than in those with the recommended Fe level, but it did not affect the Fe status. Fe deficiency significantly reduced the Fe content in the tissues. Simultaneously, Cr3 supplementation mitigated the symptoms of Fe deficiency. Fe deficiency increased TIBC and transferrin levels but reduced ferritin and most haematological parameters. However, simultaneous addition of high doses of Cr3 did not deepen these adverse changes. Our results show that the trend of changes in the Fe-Cr interaction depends on the content of these elements in the body.

Relationships Between Element Contents in Polish Children's and Adolescents' Hair

Environment, sex, and age are the main factors which determine the elemental composition of hair. The objective of the study is to determine the contents of calcium (Ca), magnesium (Mg), zinc (Zn), copper (Cu), iron (Fe), lead (Pb), and cadmium (Cd) in girls' and boys' hair in five age groups (within 1-19-year range) corresponding to successive human ontogenesis phases as well as to evaluate the relationships between these elements. Quantitative analysis has been carried out using atomic absorption spectrometry (AAS). Experimental results were analyzed using classic and principal component (PCA) statistical analyses. In particular, differences between contents of particularly Ca, Mg, and Zn in girls' and boys' hair were found, and substantial differences between age groups were stated. In general, larger amounts of Ca, Mg, and Zn as compared to boys' hair have been observed for girls' hair and higher toxic element (Pb, Cd) contents for boys were measured in some age groups. An increasing trend was found for bioelements (Ca, Mg, Zn) both for girls and boys in all age groups, while for Cu and Fe content, changes are insignificant and even decreasing for teenagers. The most frequently correlating element pairs are Ca-Mg, Ca-Zn, Mg-Zn, and Pb-Cd. Classic and PCA statistics show, in general, a satisfactory consistence. The elemental composition of hair varies depending on the gender and age of children and young people.

A comparison of arsenic exposure in young children and home water arsenic in two rural West Texas communities

Background

In a previously conducted Health Impact Assessment of a well-water dependent southwest community, arsenic (As) levels greater than the EPA Maximum Contaminant Level (10 μg/L) were identified in home water samples. The goals of this study were to test whether children from the previously studied well-water dependent community (Community 1) had higher blood As levels than children from a demographically similar and geographically nearby community dependent on a municipal water supply (Community 2); to test whether home water As levels predicted child As blood levels; and to examine how child As blood levels changed over time.

Methods

This was an observational study of 252 children aged 4 to 12 years from two communities. Children were recruited through elementary schools and tested during the school day; 204 children participated in follow-up testing. Home water samples were collected according to U.S. Environmental Protection agency recommended procedures. Child heavy metal blood levels and home water sample heavy metal levels were analyzed using inductively coupled plasma mass spectrometry. General linear regression analysis was used to test the influence of community on child As levels, and to examine the contribution of home water As levels to child blood As levels.

Results

Arsenic was detectable in all children tested. Blood levels ranged from 0.09–2.61 μg/dL; approximately 31% of children tested at Time I (79/252) had blood As values above the current acceptable limit (1.2 μg/dL). Approximately 8% of household water samples (6/76) had As levels higher than 10 μg/L. Community did not predict child blood As levels; seasonal effects differed by Community. At Time II, child blood As levels were higher in Community 2 than in Community 1.

Conclusion

A large proportion of children in the communities tested had As exposure. Home water As levels did not predict child blood As levels. Fluctuating child blood As levels by season and over time suggested the contribution of multiple factors and the need for further studies.

Reference levels of trace elements in hair samples from children and adolescents in Madrid, Spain

INTRODUCTION

Hair samples are used as a tool to evaluate environmental exposure to contaminants and metabolic status in the individual. However, the use of human hair is controversial, mainly because of the lack of well-defined reference levels. In the case of Spain, very few biomonitoring studies have investigated these issues in infants, children or adolescents.

OBJECTIVE

To establish reference levels for trace elements in children and teenagers in Madrid, Spain.

MATERIAL AND METHODS

Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure Al, As, Ag, Ba, Bi, Cd, Cr, Co, Cu, Fe, Mn, Mo, Ni, Pb, Se, Sr, Tl and Zn levels in hair samples from 648 healthy children and adolescents (253 boys and 395 girls) between April 2008 and December 2009.

RESULTS

Median levels were as follows: Al 18.5μg/g, As 0.07μg/g, Ag 196ng/g, Ba 0.5μg/g, Bi 0.01μg/g, Cd 18.3ng/g, Cr 0.4μg/g, Co 14.5ng/g, Cu 25.7μg/g, Fe 15.5μg/g, Mn 328ng/g, Mo 0.04μg/g, Ni 0.5μg/g, Pb 0.70μg/g, Se 0.5μg/g, Sr 1.29μg/g, Tl 0.28ng/g and Zn 121μg/g.

DISCUSSION AND CONCLUSION

The values of trace elements here described could be considered as possible reference ranges for hair samples from children and adolescents aged 0-18 years living in the Madrid region (central Spain). These values could also be selected as a preliminary screening tool to assess exposure sources and to generate information needed to develop prevention strategies and likewise could be a complement to other diagnostic procedures.

Assessment the Exposure Level of Rare Earth Elements in Workers Producing Cerium, Lanthanum Oxide Ultrafine and Nanoparticles

In order to assess occupational exposure level of 15 rare earth elements (REEs) and identify the associated influence, we used inductively coupled plasma mass spectrometry (ICP-MS) based on closed-vessel microwave-assisted wet digestion procedure to determinate the concentration of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in urinary samples obtained from workers producing ultrafine and nanoparticles containing cerium and lanthanum oxide. The results suggest that La and Ce were the primary component, together accounting for 97 % of total REEs in workers. The urinary levels of La, and Ce among the workers (6.36, 15.32 μg.g^-1 creatinine, respectively) were significantly enriched compared to those levels measured in the control subjects (1.52, 4.04 μg.g^-1 creatinine, respectively) (p < 0.05). This study simultaneously identified the associated individual factors, the results indicate that the concentrations in over 5 years group (11.64 ± 10.93 for La, 27.83 ± 24.38 for Ce) were significantly elevated compared to 1-5 years group (2.58 ± 1.51 for La, 6.87 ± 3.90 for Ce) (p < 0.05). Compared the urinary levels of La and Ce at the separation and packaging locations (9.10 ± 9.51 for La, 22.29 ± 21.01 for Ce) with the other locations (2.85 ± 0.98 for La, 6.37 ± 2.12 for Ce), the results show urinary concentrations were significantly higher in workers at separation and packaging locations (p < 0.01). Inter-individual variation in levels of La and Ce in urine is the result of multi-factorial comprehensive action. Further researches should focus on the multiple factors contributing to the REEs levels of the occupationally exposed workers.

Blood cadmium concentrations in Korean adolescents: From the Korea National Health and Nutrition Examination Survey 2010-2013

OBJECTIVE

To assess blood cadmium levels in Korean adolescents with respect to demographic and lifestyle factors.

METHODS

We analyzed data from the Korea National Health and Nutrition Examination Survey from 2010 to 2013, totaling 1472 adolescents aged 10-18 years. Geometric means of blood cadmium were calculated using a complex samples general linear model to compare blood levels in different demographic and lifestyle groups. Multivariate logistic regression analyses were also used to find predictors for high blood cadmium (>90th percentile).

RESULTS

The geometric mean of the blood cadmium concentrations was 0.30μg/L in Korean adolescents. Older age, type of housing (multifamily house and commercial building), smoking and alcohol consumption, and iron deficiency/iron deficiency anemia (IDA) were significantly associated with higher blood cadmium concentrations (P<0.05). Blood cadmium concentrations were not significantly affected by gender, region, body mass index status, or household income. In multivariate logistic regression analysis, independent predictors for higher blood cadmium levels included current smoker (OR=7.77), alcohol consumption (OR=4.31), living in a multifamily house or commercial building (OR=3.11-3.46), and IDA (OR=2.64).

CONCLUSIONS

Possible associations between blood cadmium levels and type of housing or alcohol consumption in adolescents are suggested for the first time in this study. Further studies are needed to elucidate the mechanism of these findings.

Toxicity and oxidative stress induced by chromium in workers exposed from different occupational settings around the globe: A review

The present review focused on the levels and toxicological status of heavy metals especially chromium (Cr) in the exposed workers from different occupational settings around the globe and in Pakistan. It was found that exposed workers from leather tanning and metal plating units showed elevated levels of Cr than the workers from other occupational settings. Cr and other heavy metals level in biological matrices of the exposed workers in different occupational settings revealed that developing countries are severely contaminated. Occupational settings from the Sialkot district, Pakistan exhibited elevated level of Cr in biological entities of the exposed workers. Review suggested that higher level of Cr exposure to the workers enhance the oxidative stress (reactive oxygen species (ROS) and hydroxyl (OH) radical generation) which may cause; cellular and molecular damage such as genotoxicity and chromosomal aberration formations, and carcinogenic effects. This review will help to understand the Cr contamination mechanisms and associated health implications in different occupational settings around the globe in general and particularly to Pakistan. This study will also assist occupational health and safety management authorities to devise or change the Cr recommended exposure limits (REL) for different occupational settings.

Evaluation of calcium and lead interaction, in addition to their impact on thyroid functions in hyper and hypothyroid patients

There is compelling evidence in support of interaction between calcium (Ca) and lead (Pb) in thyroid disorders. The aim of present study was to compare the level of Ca and Pb with thyroid hormones such as thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxin (FT4) in serum samples of hyperthyroid (HPRT) and hypothyroid (HPOT) patients of both genders. For comparative purpose, age-matched (25-50 years) subjects having no thyroid disorders were selected as referents/controls. The serum samples were acid-digested prior to analysis by atomic absorption spectrometry. The validity and accuracy of the methodology were checked by certified reference materials. The resulted data indicates that the mean values of Ca in serum samples of HPRT patients were significantly higher than those of referent subjects (p < 0.01), while reverse pattern was observed in the case of HPOT patients. The level of Pb was higher in the serum samples of both types of thyroid patients, but difference was significant in case of HPOT patients as compare to referent subjects (p < 0.01). A negative correlation was observed between serum Ca levels and TSH of HPRT patients (-r = 0.37-0.39, p < 0.01), while FT3 and FT4 have positive correlation (r = 0.49-0.52 and r = 0.46-0.47), p values <0.01. The Pb in serum had positive correlation with TSH (r = 0.48-0.51, p < 0.005), while negative correlation was observed for FT3 and FT4 (-r = 0.55-0.56, 0.5-0.54, p < 0.05) in HPRT patients. On the other hand, a reverse pattern was observed, for correlation of Ca and Pb with thyroid functions in HPOT patients.

Changed Plasma Levels of Zinc and Copper to Zinc Ratio and Their Possible Associations with Parent- and Teacher-Rated Symptoms in Children with Attention-Deficit Hyperactivity Disorder

Attention-deficit hyperactivity disorder (ADHD) is associated with alterations in the metabolism of some trace elements which may participate in the pathogenesis of this disorder. The aims of the present study were to investigate the trace element status (copper (Cu), zinc (Zn), copper to zinc ratio (Cu/Zn ratio), selenium (Se), and lead (Pb)) of ADHD children and compare them with the control group. Associations between examined elements and ratings of ADHD symptoms were also assessed. Fifty-eight ADHD children and 50 healthy children (aged 6-14 years) were included in the study. The concentrations of Cu, Zn, and Se in the plasma and Pb in the whole blood were measured by atomic absorption spectrometry. We found lower Zn level (p = 0.0005) and higher Cu/Zn ratio (p = 0.015) in ADHD children when compared with the control group. Copper levels in ADHD children were higher than those in the control group, but not significantly (p > 0.05). No significant differences in levels of Se and Pb between both groups were found. Zinc levels correlated with parent-rated score for inattention (r = -0.231, p = 0.029) as well as with teacher-rated score for inattention (r = -0.328, p = 0.014). Cu/Zn ratio correlated with teacher-rated score for inattention (r = 0.298, p = 0.015). Significant associations of Se and Pb with parent- and teacher-rated symptoms were not observed. The results of this study indicate that there are alterations in plasma levels of Cu and Zn as well as significant relationships to symptoms of ADHD.

Temperature controlled ionic liquid-based dispersive micro-extraction using two ligands, for determination of aluminium in scalp hair samples of Alzheimer's patients: a multivariate study

A green and sensitive temperature controlled dispersive liquid-liquid microextraction (TIL-DLLME) methodology based on the application of ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, [C4mim][PF6], as an extractant solvent was proposed for the preconcentration of trace levels of aluminium (Al(3+)) in scalp hair samples of Alzheimer's (AD) patients, prior to analyzing by flame atomic absorption spectrometry (FAAS). The Al(3+) was complexed with 8-hydrooxyquinoline (oxine) (L1) and 3,5,7,2'-4' pentahydroxy flavone (morin) (L2) separately and then extracted by IL at temperature (50±2.0°C). Some effective factors that influence the TIL-DLLME efficiency such as pH, ligands concentrations, volume of IL, ionic strength, and incubation time were investigated and optimized by multivariate analysis. In the optimum experimental conditions, the limit of detection (3s) and enhancement factor were 0.56 μg L(-1), 0.64 μg L(-1) and 85, 73 for both ligands, respectively. The relative standard deviation (RSD) for six replicate determinations of 100 μg L(-1) Al(3+) complexed with oxine and morin were found to be 3.88% and 4.74%, respectively. The developed method was validated by the analysis of certified reference material of human hair (NCSZC81002).and applied satisfactorily to the determination of Al(3+) in acid digested scalp hair samples of AD patients and healthy controls. The resulted data shows significant higher level in scalp hair samples of AD male patients with related to referents of same age and socioeconomic status.

Monitoring lead in hair of children and adolescents of Alcalá de Henares, Spain. A study by gender and residential areas

In recent years there has been an increased interest from the European Union (EU) in the development of large Human Bio-monitoring (HBM) studies across Europe, especially biomonitoring toxic metals. In Spain, most studies using hair as a biomarker have been conducted to determine occupational or industrial exposures, and have involved adult populations. Few studies have involved adolescents and children, despite these groups being sensitive to environmental contamination and pollutants. Therefore, the objective of the present study was to determine the degree of lead exposure in children and adolescents residing in Alcalá de Henares, Spain. Lead poisoning is the number one toxicological threat in the environment. So, lead (Pb) was selected as it is a persistent environmental contaminant, is measureable and is also a neurotoxin that can affect brain development. The city of Alcalá de Henares was divided into four zones to determine the influence of residence area on Pb levels. A range of other variables including age and gender were also considered within the study. The study comprised 115 children (6-9 years old) and 96 adolescents (13-16 years old). There was a significant difference between the levels of Pb in the hair of adolescents, for different gender and area of residence (p<0.001 and p<0.01 respectively). There was no significant difference in the Pb levels in hair of children, for different gender or area of the city. The levels of Pb were significantly (p<0.001) elevated in children compared to adolescents (1.48 vs. 0.70 μg/g), and there was a significant difference in Pb levels in male and female adolescent hair (0.53 vs. 0.77 μg/g) (p<0.001). The association observed between areas of residence and the Pb level in hair of the adolescent group could be mainly attributed to dietary habits and/or socioeconomic status.

Iron deficiency increases blood concentrations of neurotoxic metals in children

Iron deficiency affects approximately one-third of the world's population, occurring most frequently in children aged 6 months to 3 years. Mechanisms of iron absorption are similar to those of other divalent metals, particularly manganese, lead, and cadmium, and a diet deficient in iron can lead to excess absorption of manganese, lead, and cadmium. Iron deficiency may lead to cognitive impairments resulting from the deficiency itself or from increased metal concentrations caused by the deficiency. Iron deficiency combined with increased manganese or lead concentrations may further affect neurodevelopment. We recently showed that blood manganese and lead concentrations are elevated among iron-deficient infants. Increased blood manganese and lead levels are likely associated with prolonged breast-feeding, which is also a risk factor for iron deficiency. Thus, babies who are breast-fed for prolonged periods should be given plain, iron-fortified cereals or other good sources of dietary iron.

"Reference values" of trace elements in the hair of a sample group of Spanish children (aged 6-9 years) - are urban topsoils a source of contamination?

Human hair is used as a biomonitor to evaluate the environmental exposure to contaminants in the individual. However, the use of human hair is controversial, mainly because reference levels for pollutants in hair have not yet been set. In the case of Spain, few biomonitoring studies have involved infants and children. A biomonitoring study was conducted to investigate the possible normal values of trace elements of toxicological concern in children aged 6-9 years from the city of Alcalá de Henares, Community of Madrid (Spain), following the methodology and strict inclusion criteria previously developed by our group. Levels of Al, As, Be, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Sn, Ti, Tl, V and Zn were monitored in scalp-hair from 117 healthy children (47 boys and 70 girls) between April and May of 2001. The levels of trace elements here described could be considered as possible "reference values" for children aged 6-9 years resident in the Community of Madrid. These values might also be selected as a preliminary screening tool to evaluate if a Spanish child has been exposed to any of the contaminants studied here. This study also investigated whether local urban topsoils were a source of metals for this population.

The influence of endodontic broken stainless steel instruments on the urinary levels of iron

Previous studies on the endodontic broken stainless steel instruments have mainly focused on retrieval of specimens. However, the systemic consequences of the retained separated instruments need an investigation. The current study aimed to evaluate the correlation between broken stainless steel instruments inside the root canal space and the urinary level of iron (Fe) in patients. Sixty near-aged and same-gender patients were selected. Thirty patients in the control group had no endodontic treatment in their history, while the other 30 patients in the endodontic group had broken stainless steel instrument. The urine samples were collected in iron-free containers. All specimens were refrigerated for 1 day and then subjected to Fe level measurement by electrothermal atomic absorption spectrometry. Data were analyzed by Kolmogorov-Smirnov and t tests at P < 0.05. The correlation coefficients of age and sex were also evaluated in relation with Fe levels in the urine. The level of Fe did not show any significant increase in the experimental group (P > 0.05). There was a positive correlation between age and Fe levels of endodontic and control groups. However, the joint effects of age and sex on Fe levels were different for the two groups. The presence of broken stainless steel instruments inside the root canal space did not elevate the level of Fe in the urine of patients. However, this value was positively correlated with the patient age.

Iron deficiency increases blood cadmium levels in adolescents surveyed in KNHANES 2010-2011

Discrepancies have been reported in the relationships between iron and cadmium concentrations. The distribution of blood cadmium concentrations was assessed in a representative sample of Korean adolescents participating in the Korean National Health and Nutritional Examination Survey (KNHANES) 2010-2011, and the association between blood cadmium and iron concentrations was determined. This study was based on data from KNHANES, in which a rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the noninstitutionalized civilian population in South Korea. Serum ferritin was categorized as low (<15.0 μg/L), low normal (15.0-<30.0 μg/L for girls, 15.0-<50.0 μg/L for boys), or normal (≥30.0 μg/L for girls, ≥50.0 μg/L for boys), and the association between serum ferritin and blood cadmium concentrations was assessed after adjustment for various demographic and lifestyle factors. The geometric mean (GM) of blood cadmium was significantly higher among both boys and girls in the low than in the normal ferritin group. After controlling for covariates, multiple regression analysis showed that blood cadmium concentration was inversely correlated with serum ferritin concentration in both boys and girls. In conclusion, iron deficiency is associated with increased blood cadmium concentrations in a representative sample of Korean adolescents, as evaluated in KNHANES.

Trace Element Status (Iron, Zinc, Copper, Chromium, Cobalt, and Nickel) in Iron-Deficiency Anaemia of Children under 3 Years

Aim. To determine trace element status and aetiologic factors for development of trace elements deficiencies in children with iron-deficiency anaemia (IDA) aged 0 to 3 years. Contingent and Methods. 30 patients of the University Hospital, Pleven, Bulgaria-I group; 48 patients of the Sumy Regional Child's Clinical Hospital, Sumy, Ukraine-II group; 25 healthy controls were investigated. Serum concentrations of iron, zinc, copper, chromium, cobalt, and nickel were determined spectrophotometrically and by atomic absorption spectrophotometry. Results. Because the obtained serum levels of zinc, copper, and chromium were near the lower reference limits, I group was divided into IA and IB. In IA group, serum concentrations were lower than the reference values for 47%, 57%, and 73% of patients, respectively. In IB group, these were within the reference values. In II group, results for zinc, cobalt, and nickel were significantly lower (P < 0.05), and results for copper were significantly higher in comparison to controls. Conclusion. Low serum concentrations of zinc, copper, cobalt, and nickel were mainly due to inadequate dietary intake, malabsorption, and micronutrient interactions in both studied groups. Increased serum copper in II group was probably due to metabolic changes resulting from adaptations in IDA. Data can be used for developing a diagnostic algorithm for IDA.

Iron Deficiency is Not Associated with Increased Blood Cadmium in Infants

OBJECTIVES

To determine whether blood cadmium concentration is elevated in iron-deficient infants.

METHODS

Blood cadmium and serum ferritin concentrations, serum iron/total iron-binding capacity (Fe/TIBC) and complete blood counts were measured in 31 iron deficient and 36 control infants, aged 6-24 months. All 31 iron-deficient infants received iron supplementation for 1-6 months.

RESULTS

Blood cadmium concentrations were measured again in 19 of the iron deficient infants after their ferritin levels returned to the normal range. The mean blood cadmium concentration did not differ significantly in iron deficient and control infants. The mean blood cadmium concentration in the 19 iron-deficient infants was not significantly altered by ferric hydroxide treatment, while their hemoglobin, ferritin, and Fe/TIBC (%) concentrations were significantly higher after than before treatment.

CONCLUSION

These findings indicate that iron deficiency does not increase blood cadmium concentrations in infants, in contrast with the effects of iron deficiency on manganese and lead concentrations.