Studies on Fluorine and Other Related Material in the Rice : Part 1. The fluorine content of lowland non-glutinous unpolished rice and its geographical correlation with mortality from gastric cancer

摘要

Through the courtesy of Food Management Training School, Mikawa-Ichinomiya, the author was able to determine of the fluorine content of 279 samples of lowland non-glutions unpolished rice from 38 prefectures of Japan in 1960. We are determinated of Aluminium-Hematoxylin method. The results obtained are as follows: (1) Two hundred and seventy-nine samples of lowland non-glutious unpolished rice averaged 19.963ppm of fluorine contained. (2) A comparison of different grades showed an increase of fluorine content with deterioration in quality. The smallest amount of fluorine were contained in first class rice samples, and the largest of fluorine in those of the fifth class rice samples. (3) A greater variation in the fluorine contents ws by locality than by variety. The rice samples from Nara and Niigata Prefecture, cancerous districts, contained nearly sextuple as much fluorine as those of the southern Kyushu, particularly in Kagoshima Prefec., non-cancercus distirict. (4) There was a positive correlation at 0.1 % for the level of significance between the fluorine contents and male corrected death rate from gastric cancer in Japan, in 1960, the correlation coefficient being +0.615 of 38 drefectures, and a correration between the contents and female corrected death rate was found positive at the high level of significance.