Gi-ichiro Tanaka

Reference Japanese Man-ii. Distribution of Strontium in the Skeleton and in the Mass of Mineralized Bone

AbstractThe distribution of stable strontium concentration in different bones, as well as in a single bone, was studied. Dependence of the stable strontium-to-calcium ratio upon age was observed. A non-uniform distribution of the stable strontium to calcium ratio was found in both the skeleton and t

Reference Japanese man--I. mass of organs and other characteristics of normal Japanese.

The weight of organs measured from autopsy cases of normal Japanese adults, children, and infants is presented for the purpose of approaching a Reference Japanese Man. The skeletal content and the daily intake of alkaline earth elements are given. The lower rate of transfer ( K 2 ) to the thyroid gland of ingested radioiodine, as well as the remarkably shorter biologist half-life than the data adopted by ICRP, is also proved as a result of this study.

Daily intake of 11 elements in relation to reference Japanese man

Diet samples were collected by a duplicated portion method from 31 locations in Japan in both the summer and winter of 1981. The ashed samples were analyzed with an inductively coupled plasma atomic-emission spectrometer (ICP-AES) for 11 elements: Na, K, P, Ca, Mg, Zn, Mn, Al, Sr, Cu and Ba. Average daily intake was as follows: Na--4.5 g, K--1.9 g, P--0.92 g, Ca--0.56 g, Mg--0.20 g, Zn--7.1 mg, Al--4.0 mg, Mn--3.4 mg, Sr--2.3 mg, Cu--1.3 mg and Ba--0.36 mg. A tendency for higher mineral intakes was found in central Japan. These were the highest in the Chubu area followed by the Kanto and Kinki areas. Lower mineral intakes, below the averages for Japan, were found in western Japan, especially in the Chugoku and Shikoku areas. Daily intake of most elements, except Na, Mn, and Sr, was found to be 40-70% of the levels of Reference Man, which were reported by International Commission on Radiological Protection (ICRP) for the Western Europeans and North Americans. Daily intake of Na, Mn and Sr was almost the same in both cases.

Actinides concentrations in human tissues.

Fallout 239,240Pu concentrations in some autopsy tissues from the general population in Japan are described. Body burden and relative distribution among tissues of plutonium were obtained by extrapolating using the mass of relevant tissues of the normal Japanese adult. 239,240Pu-to-90Sr body burden ratio was obtained. ICRP models were used to estimate body burden and relative contribution of ingestion intake. Need for data on the intraskeletal distribution of fallout plutonium and more information on gastrointestinal absorption in man was stressed.

Determination of thorium and uranium in total diet samples by inductively coupled plasma mass spectrometry

The Th and U contents in total diet samples were determined by inductively coupled plasma mass spectrometry (ICP-MS). The internal standardization method was adopted to compensate for non-spectral interferences arising from matrix elements in the sample solutions. Concentration levels of the order of pg ml–1 of Th and U in the total diet sample were determined easily and rapidly by using Bi as an internal standard. The mean concentrations and standard deviations of Th and U in the total diet samples were found to be 25 ± 12 and 44 ± 20 ng g–1 of ash, respectively (for n= 62).

Simultaneous multielement analysis of various human tissues by inductively-coupled plasma atomic-emission spectrometry

Human soft tissues were analysed by inductively-coupled plasma atomic-emission spectrometry (ICP-AES) for twelve elements. The tissues had been vacuum-dried for storage and were dry-ashed at low temperature and then digested with nitric acid prior to analysis. Accuracy and precision were examined by analysing NBS Standard Reference Material 1577 Bovine Liver. For P, K, Na, Mg, Ca, Fe, Cu, Zn and Cd, the concentrations obtained were within 4% of the certified or informational values. It was found that cerebrum, cerebellum, heart, kidney, liver, pancreas, spleen and muscle samples in portions of less than 1 g dry weight could be conveniently analysed for these elements.

The rapid determination of barium in bone by atomic absorption spectrophotometry

Abstract A rapid and precise method for the determination of barium in bone is presented. Barium as the nitrate is directly separated from calcium by co-precipitation with added strontium using fuming nitric acid. Atomic absorption measurements are made at 553.6 nm using a nitrous oxide-acetylene flame in the presence of strontium and potassium, and being free from noise due to the emission of CaOH. In order to improve accuracy and speed a radioactive tracer is used.

Determination of alkaline-earth metals in foetus bones by inductively-coupled plasma atomic-emission spectrometry

Alkaline-earth metals in human bone samples have been determined simultaneously by inductively-coupled plasma atomic-emission spectrometry (ICP-AES). Results obtained by atomic-absorption spectrometry for Mg, Sr and Ba, and complexometry for Ca, have been compared with those by ICP-AES for a laboratory-control bone sample. Accuracy and precision were examined by analysing the IAEA animal bone standard (H-5). Agreement with the certified values to within 5% was obtained. The concentrations of the elements in foetal bone have also been determined.

Concentration of239, 240Pu in human bone

Some results of the plutonium determination for bone ash samples collected in Japan are presented. Mean239,240Pu concentration in the adult vertebra was 0.53 pCi/kg of ash during the period 1978 through 1983. The data are roughly in coincidence with estimated plutonium concentrations in the trabecular bone from reported air plutonium concentrations using the ICRP model and metabolic data, and weight of bone in Reference Japanese Man.