Japanese-radish, Welsh onion, and Chinese cabbage were stored in soil, snow, straw-made bag, or under floor, etc. Reduced form of vitamin C in these vegetables was determined by 2, 6-dinitrophenol-in-dophenol titration procedure. Considering the weight loss caused by evaporation of moisture on storage, Japanese-radish and Chinese cabbage contained 66 and 67 per cent of initial amount even after 3 months when stored in snow, and significantly higher than 20-50 per cent observed by other methods of storage. In the case of Welsh onion, the loss of vitamin C was only about 30 per cent when stored in straw-made bag, but 50-90 per cent in the others.
Linoleic acid and cholesterol in serum were determined monthly on seven healthy subjects. Their linoleic acid contents ranged from 34.2% to 44.5%, entirely in inverse proportion to their age, but their cholesterol content had no correlation with linoleic acid content in this case. Monthly personal fluctuations of both substances seemed to lie in pretty narrow range.
It is an important problem to investigate the relation between fallout and contamination of food-chain. Therefore, as first step, we have measured the contents of Strontium-90 in Japanese daily diets since 1960. The survey was performed as follows, twice a year: in August and in November. Because in August, Japanese take summer vegetables and in November they take autamnal vegetables and the vegetables are the most essential sourse of Calcium in Japan. In this survey, Japan was divided into 7 areas and from the each area one prefecture was chosen so as to select the sample on both sides of Japan: on Pacific Ocean and Japan Sea. They are Hokkaido, Miyagi, Saitama, Ishikawa, Mie, Ehime and Kumamoto. Then one town and one village were chosen from each prefecture, and ten families were selected from the town and village as subjects of this survey. In each family, daily diet for adult per day for one person was collected. Besides the diet for adult, daily diets for children of 5-6 years old were collected from the suburban families in four prefecture: Hokkaido, Saitama, Ishikawa and Kumamato, to compare them with those of the adults. The collected samples were dried and were burned to ash and the amounts of Sr-90 were measured by the standard method in Japan. The results were shown on Table 1-5 and Figure.
The fear of increased dietary contamination with radioactive elements from fallout has stimulated considerable effort towards finding a safe and effective means of decreasing the body burden of radioactivity. In continuance to the survey in 1960, we have been carrying out the survey in 1961, too. Before the opening of this survey, Japan was divided into 8 areas, afterward was added 3 areas. One prefecture was chosen from the different area and stillmore, one urban district and one suburban district were chosen from different prefecture. This survey was performed twice a year. As subjects in this survey 10 families were selected from the different district, but 20 families were selected from FUKUOKA, NIIGATA, and TOKYO. In each family, daily diet for adult per day per person was collected, as regards to child, it was collected by the same means to adult. The collected samples were dried and were burned to ash and the contents of Sr-90 in daily diet were measured by the method of furming nitric acid. The results were shown on a table. The tendency of contaminated degree in similar compare with results of 1960, namely, the North-East areas, the North-West areas and the South part of Japan are higher level more than another areas. Now, when to compare with adults and children about value of S. U., its value of children higher than that of adults. This is a very important fact, therefore, we must search to protective agents to hazard occur by radioactive elements through the alimentary tract.