EXCHANGE OF PHOSPHORUS I\ TEETH 



171 



o 



content of the blood will depend on the fluorine content of the food and 

 water taken up. It is thus easy to explain why the fluorine content of the 

 tcH'th varies within wide limits (see Table 4). The high fluorine content 

 f 1he teeth of human beings living at Colorado Springs is due to the 

 high fluorine content of the water which amounts to up to 2 mgm per 

 Uler. The high fluorine content of the teeth of some North African 

 sheep is to be explained by the high fluorine content, above 0.02%, 

 of the soil on which they graze. On such soil plants of high fluorine 

 content grow, are eaten by the sheep, and lead to an abnormally high 

 fhiorine of the blood plasma, which in turn leads to an abnormally high 

 I'eplacement of OH^ by F in the teeth^' 2. 3- 4 



Table; 4. Flt'orink Context of Teeth Ash 



Mani 



Marine animals 

 Rats2 



Man^ New York 



Man New York 



Man^ Colorado Springs 



Man Colorado Springs 



Man* 



Man* 



Calves* 



Calves* 



Sharks* 



Sheep, young from neighbourhood of Norwe- 

 gian ahiminium factory where fluorides are 

 utilised* 



Sheep^ North Afric-a 



Sheep^ North Africa, attacked l)\- fluorine 

 disease 



The much higher fluorine content of animals living in sea watci is 

 also due to the comparatively high fluorine content of the latter. In 

 1 he same way that F replaces OH in the apatite lattice, magnesium 

 for example replaces calcium. Human dentine ash has a magnesium 

 content*^ of 1.18 — 1.39% whereas human enamel ash has only 0.42%. 

 While the calcification of the tooth tissue is presumably the result of 

 specific cell activity, it is quite possible that later on a replacement of 



(DR. Klement, Naturwiss. 21, 662 (1933). 



(2)R. R. Sharpless and E. V. McCollum, J. Xutnt. 6, 163 (1933). 



'3)H. Boi-ssEVAiN and W. F. Drea, J. Dent. Bes. 13, 495 (1933). 



(*)K. RoHOLM, Fluorine Intoxication, p. 260. Copenhagen (1937). 



(5) M. Gand, a. Chavnot and M. Langi.ais, (1934.) Bull. Innt. Ili/g. Maroc 



Xos. I-II. 

 («)M. M. Murray, Biochem. .7. 30, 1568. (1936.) 



