Abstract
1) Average fluorine content of normal human enamel was 99.6μg/g in man and 106.8μg/g in woman, while in dentin it was 284.2μg/g in man and 276.1μg/g in woman. There was no difference due to sex or age.
2) Fluorine contents in Japanese usual foodstuffs were determind. Unusual high content of fluorine were found in marine products: such as in shrimp (50), salted and dried sardines (40), sea weed (6-14), fresh sardine (8-19), Jack mackerel (6-13ppm). In animal meat and its products, it was relatively low (1-2ppm), and also in vegetables (0.1-0.9ppm), in cereals and its products or fruits (0.2-0.8ppm). Table salts was usually contained relatively high fluorine.
Dried green tea leaves contained extraordinary high fluorine (186-390ppm), but the green tea (infusion by hot water) contained only 0.1-0.7ppm.
3) The approximate daily intake of fluorine by Japanese adults was estimated from the data mentioned above, taking into consideration of the fact that Japanese takes much fish products and drinks much green tea in place of water and black tea.
The results were as follows; 0.4-1.8mg of fluorine from foodstuffs, 0.07-0.86mg from green tea and 0.01-0.08mg from drinking water. Thus the total sum of fluorine intake will be 0.48-2.64mg per day for adults, according to the variety of menu and tea consumption habits.
