FLUORINE IN WATER SUPPLIES—VAN BURKALOW 21 
well waters of the humid East contain little or no fluorine, whereas in 
some parts of the drier West they contain toxic amounts. In Arizona, 
for example, most of the high fluorine concentrations are found in 
shallow wells.” This is not true, however, in all dry regions. In 
the Dakotas it is typically the deep artesian waters that have a high 
fluorine content, and usually the shallow well waters are nontoxic. 
Since in areas of low rainfall the fluorine concentration varies with 
variations in geological conditions, it seems unsafe to attribute the 
contrasts between the humid East and the drier Great Piains to cli- 
matic differences. Differences in the nature of the rocks are REObaEny 
more important. 
OTHER PATHOLOGICAL EFFECTS OF FLUORINE 
It is known that ingestion of large amounts of fluorine affects the 
human system in general, producing changes in the bony structure 
simulating rheumatic conditions. Cases of such chronic fluorine poi- 
soning caused by excessive fluorine in the drinking water have been 
reported from India, the Argentine Republic and South Africa.” 
Experimental studies indicate that other possible effects of fluorine 
are enlargement of the thyroid gland, producing exophthalmic goiter; 
reduction of the calcium content of the blood, disturbing body metab- 
olism; rendering of the bones more fragile, causing an unusual num- 
ber of bone fractures; and development of high blood pressure and 
nervous disorders. 
As far as is known, these types of fluorosis have not been reported 
in the United States. Since the minimum amounts of fluorine needed 
to produce them have not been determined, it is uncertain whether 
they are entirely absent, even where there is enough fluorine to cause 
dental fluorosis, or have merely not been recognized because of their 
similarity to disorders caused by other factors. A recent study * of 
men and boys from regions with water supplies containing from 0.0 
to 5.0 p. p. m. of fluorine shows that bone-fracture experience, height, 
and weight are not related to this degree of fluorine exposure. More- 
over, it was found * that a large percentage of the fluorine ingested 
277 Smith, H. V., and Evans, ‘Tindall, A fluorine study of wells, Water Works Engineering, 
August 13, 1941 (reprint). 
80 For a discussion of the reports and of the general manifestations of bone fluorosis see 
Ockerse, op. cit. 
31 For a summaty of these studies see Abbott, G. A., The fluoride content of North Dakota 
ground waters as related to the occurrence and distribution of mottled enamel, North Da- 
kota Geol. Surv. Bull. 9, 1937: McClure, F. J., and Mitchell, H. H., The effect of fluorine on 
the calcium metabolism of albino rats and the composition of the bones, Journ. Biol. Chem., 
vol. 90, pp. 297-320, 1931; McClure, F. J., Fluoride domestic waters and systemic effects. 
I, Relation to bone-fracture experience, height, and weight of high-school boys and young 
selectees of the Armed Forces of the United States, Publ. Health Reps., vol. 59, pp. 1543- 
1558, 1944. 
82 McClure, op. cit. 
™ McClure, F. J., and Kinser, C. A., Fluoride domestic waters and systemic effects. II, 
Fluorine content of urine in relation to fluorine in drinking water, Publ. Health Reps., vol. 
59, pp. 1575-1591, 1944. 
