Determiantion Of16Trace Elements In Plasma/serum And Zinc Nutritional Assessment Of Children In Rural Areas Of China In2002/2012

Background and ObjectivesTrace elements are closely related with health, nearly0.012%accounting of the total weight of human tissues, involving in coenzyme factors and metabolism and build body tissues, enzyme reactions, electrolytes balance, and cell biological function. It is essential to maintain human health nutrients.Children are a major health concern groups, who characterized by their rapid growth and development, and the vulnerable ability to regulate to face more health risks. Assessment of the nutritional status of children of trace elements is carried out and the essential precondition for children nutrition interventions. So far, the national survey of trace elements was to scant, it is limited for a special investigation of trace elements levels of children, has seriously affected the health evaluation to assess trace element nutrition. Therefore, this study was based on2002/2012CNNHS, to assess the trace elements of rural children, which was helpful to assess the impact of trace element nutrition status of rural children during the past10years and to study of trace elements nutritional status of children in rural areas, to carry out trace element nutrition and health risk assessment, formulation of relevant nutrition intervention programs for children and the intervention cost-effectiveness assessments.Study population and method1. Analysis method of HR-ICP-MSTo optimize HR-ICP-MS by a single variable method and to adjust carrier gas flow rate and ion lens voltage in order to improve sensitivity, stability, resolution, and reduce oxides, doubly charged ion interference. The plasma/serum samples were diluted directly using0.5%HNO3in1:20. Using partial methodology validation procedures to investigate the instrument detection limit, limit of method detection, linear ranges, linear equations. In addition, plasma quality control samples (Clinchek, Level-1, Level-2) and3-levels pooled plasma spiked recovery experiment were employed in the accuracy and precision of the method validation.2. Determination of16plasma/serum trace elements of children in rural areas of China2002/2012The present study was based on the plasma samples collected in2002CNNHS combing with the individual information. It was employed the stratified random sampling by the rural type, genders and age factors,10%of the sampling ratio. While in2012CNNHS, we employed the formula of minimum sample size to estimate the size, and randomly selected representative samples by genders, age, proportional sampling of children aged6-12year at each monitoring site. Selection plasma/serum samples according to the blood ID, excluding hemolytic samples and replaced and complemented by the principle of neighboring. To analyze plasma/serum16trace elements by HR-ICP-MS.3. Zinc nutritional status survey of children in2002and2012Based on2002/2012CNNHS, we had analyzed the16plasma/serum trace elements concentrations of children in rural areas. Meanwhile, the relevant information on children dietary questionnaires and the physical examination records for2002CNNHS were collected. To calculate the level of dietary zinc intake by using3days24hours dietary questionnaires information combined with2002Chinese food composition table. And based on the examination records of children to calculate Z score.Results1. Analytical Method of HR-ICP-MSThe method of HR-ICP-MS combined0.5%HNO3in1:20direct dilution of the plasma/serum samples were prepared16of trace elemental analysis. The detection limit of the range0.005-1.854μg/L, working curve ranges:Fe, Cu, Zn, Rb:0-100ppb. B, Sr, Se:0-10ppb. Al, Co, Mn, Pb, Mo:0-1ppb. Cd, V, Cr, As:0-0.5μg/L. Clinchek trace elements of plasma QC (Level-1, Level-2) validation:the accuracy ranged from84.8-117.3%for each element, intra-day precision ranged from1.1-9.0%, inter-day precision ranged from3.2-10.9%. Additionally,3levels of spiked recovery tests were confirmed. In detail, the recoveries ranged from89.2-121.3%, intra/inter-day precision ranged from0.7-5.0%,1.2to10.0%, respectively.2. References of16plasma/serum trace elements of children in rural areas of China2002、2012The concentrations of16plasma trace elements of children in rural areas of China2002were listed in table1. Due to the abnormal distribution of the data of trace elements, so the results were presented by0.5%of trimmed mean, genometric mean, median, P5and P95. Table1. Concentrations of16plasma trace elements of Children aged of3-12years in rural areas of China2002The concentrations of16serum trace elements of children in rural areas of China2002were listed in table2. Due to the abnormal distribution of the data of trace elements, so the results were presented by0.5%of trimmed mean, genometric mean, median, P5and P95. Table2. Concentrations of16serum trace elements of Children aged of6-12years in rural areas of China20123. Comparison of zinc nutritional status and assessment of children in2002and2012According to the results of zinc nutritional assessment2002, the overall prevalence of zinc deficiency was44.3%, which was higher than20%of zinc deficiency risk threshold suggested by IZiNCG. Dietary intake assessment shows that the dietary zinc intake inadequacy rate was16.3%, compared to the reference of IZiNCG, which was located in moderate zinc deficiency. Height for age Z score suggest that the overall stunting rate of children was19.1%, the stunting rate of children for zinc deficiency was21.0%; the children under5years of age, and22.9%of the children was stunting.The geometric mean plasma zinc concentration of rural children of720.0μg/L and the prevalence of zinc deficiency was43.8%in2002survey, and the GM serum zinc concentration was858.3μg/L, and the prevalence of zinc deficiency was10.3%in2012survey. Compared to the2002survey, the zinc status of rural children has been greatly improved.Conclusions1. The method of HR-ICP-MS combined0.5%HNO3in1:20direct dilution of plasma/serum samples was established. The technique is reliable and easily operate, which were in line with the large quantities of samples, and multi-elemental analysis in large-scale of investigation.2.16plasma/serum trace elements were establishment of children in rural China of2002/2012. Comparison of the change for16trace elements during past10years, which is helpful to formulate the relevant trace elements reference and to the related trace element nutritional health assessment.3. Based on the IZiNCG indicators, zinc nutritional status of children aged3-12was very serious in2002. But zinc nutritional situation had been significantly improved during past10years.