1954 Volume 18 Issue 3 Pages 201-204
According to Kuroda there exist two kinds of radioactive springs in Japan, namely radium- or radon-spring and thorium- or thoron-spring. The strongest thoron spring was found in Misasa, its thoron content being 70×10-9 curie units per liter.
Using Warburg's apparatus, powdered monazite within it as a source of thoron, oxygen consumption of human erythrocytes proved to be suppressed by thoron under 1/2 of the control without monazite.
The decrease in the oxygen consumption of erythrocytes by thoron returned to the control level after the removal of monazite from the side chamber and by refreshing the air in the gas space. Namely inhibition of blood cell respiration by thoron is reversible.
After hemolysis of erythrocytes by adding distilled water, oxygen consumption decreased under 1/10 of the control and inhibition of respiration by thoron became no more proved.
Concentration of thoron in the gas phase was estimated to be about 17×10-9 curie units per liter.