To study the relationship between sodium intake and urinary sodium excretion among young women, we carried out the following experiment. Experimental diet was consisted of three different levels of dietary NaCI intake (stage one, stage two, and stage three). A target levels of dietary NaCI intake was 5 g per day for stage one, and 13 g per day for stage two, and 20 g per day for stage three. For each stages, nine female students were taken one experimental diet for consecutive three days, and were collected all the urine through the experimental period. Sodium contents of a collected urine samples and all the foods included in experimental diet were analyzed for comparing urinary excretion rate of sodium on three stages. The following results were obtained. Mean urinary excretion rate of sodium for each stages was 62% for stage one, 75% for stage two, and 103% for stage three, respectively. Strong positive correlation was obtained between sodium intake and urinary sodium excretion.
In the aim to mitigate the toxicity of cadmium polluted in water environment, the organic chemicals which were considered to chelate with cadmium, were investigated in rearing Oryzias latipes. The survival ratio of the fish reared in 3 × 10-5 M Cd was 50% after 21.5 h, and this concentration was applied through this experiment. Fourteen sodium salts of 10-4 M organic acids prolonged the longevity of the fish.Tricarboxylates were the most effective. Four chelating agents were also effective and EDTA was the most. Glutaminate was little effective, whereas another amino acid cysteine decreased the survived. Three mitigative chemicals, EDTA, cis-aconitate (cis-Aco) and iso-citrate (iso-Cit) and the promoting chemical, cysteine (CySH) were investigated again at the relative concentrations shown in Table 1. The effects were shown obviously at above 0.5 relative concentrations. The effect of EDTA remained even after 48 h, whereas those of tricarboxylates did not. Co-existence of EDTA with cis-Aco and with iso-Cit seemed to increase the effects of these tricarboxylates. Co-existence of EDTA with CySH cancelled the effect of this amino acid and, at high relative concentration, a mitigative effect was observed.
For this proposed study, the silicon compounds, which are commonly applied on a refinery industry, after the administrations to mice were investigated on the mutagenicity in relation to distributions in various organs and excretions to urines in comparison with the chromium compounds. The results of these investigations were as follows: 1) The administration of silicon compounds such as silicon dioxides and sodium methasilicate existed a weak positive mutagenicity by the detection of "umu-lac" kit using Salmonella typhimurium TA1535/psk 1002 strain under the presence of S-9 mix. 2) The administration of hexavalent chromium compounds proved a potential positive mutagenicity, and, the trivalent chromic chloride also showed a weak positiveness. 3) Regarding the organ distribution of silicon and chromium compounds in the tissue of mice, there showed a high concentration in liver, kidney and blood at 180 minutes after the intraperitoneal injection of these compounds. The excretion of these compounds to urines was rapid, and, it seemed that the rate of accumulation of both compounds in these organs was low. 4) The workers in a refinery factory exhibited a significantly higher mutagenic activity in their urines than that of the controls. According to these results, the mutagenicity in urines was affected by the sort of occupations and smoking habitudes .However, the relationship between the mutagenic activities in urines and the excretion rates of silicon in urines was not obviously recognized.