Elemental transfer from Chinese soil via the diet to the whole human body.

Based on results from recent studies of elemental dietary intake and organ or tissue content for adult Chinese men, quoted nationwide elemental concentrations in Chinese soil and newly published national average consumption of dietary foods, values of both transfer coefficients and discrimination factor (DF) for transfer from soil via the diet to both critical organs and the whole body have been calculated for important elements in radiation protection, including alkaline earths, alkali metals, rare earths and other related elements. These calculations have used both the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) model and the DF method. In the UNSCEAR model, the basic parameters used to describe the transport of radionuclides are the transfer coefficients P(ij), which describe the relationship of concentrations or other amounts between compartment i and the following compartment j, whereas the DF is the ratio between the transfer coefficients for one element and a chemically similar element. From a comparison of the transfer coefficients of different elements for a particular transport pathway, those for alkaline earths are generally speaking higher than those for halogen elements and alkali metals, whereas those for rare earth elements, U and Th are lower. Relative to Ca, the DFs of transfer from soil to diet and from diet to critical organs or the whole body for the other alkaline earth elements and Pb are all less than 1, the DFs for the other elements decrease with increasing or decreasing atomic number. For alkali metals, the DFs of transfer from diet to critical organs and the whole body seem to increase with increasing atomic number, but those from soil to diet decrease with increasing atomic number.

Elemental contents in organs and tissues of Chinese adult men.

OBJECTIVE: To provide basis of reference values for relevant parameters of Chinese Reference Man. METHODS: Eighteen kinds of major organ or tissue samples, including muscle, rib, liver, and so on, were obtained from 4 areas (Hebei, Shanxi, Jiangsu, and Sichuan provinces) with different dietary patterns in China in autopsy of 16 healthy adult men, who had just encountered sudden deaths. At the same time, whole blood samples were collected from 10 volunteers living in each of these areas. The concentrations of 56 elements in these samples were detected by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS) techniques. Based on obtained concentrations and reference values of these organ or tissue weights for Chinese Reference Man, the relative elemental burdens in these organs or tissues as well whole body were also estimated. RESULTS: The concentrations of 56 elements in 18 main organs or tissues were determined all together and their elemental organ or tissue and whole body burdens were estimated. Furthermore, the distributions of important elements for radiation protection in these organs or tissues were emphatically discussed. CONCLUSION: By summing with past related results, the total results obtained from the series of research may provide more reliable and better representative basis of these reference values for Chinese Reference Man than before.