1178 



RADIATION BIOLOGY 



panying tabulation. More than 87 per cent of primary tumors in these 

 miners originated in the lung. 



Early investigators attributed the high incidence of pulmonary tumors 

 to inhalation of arsenic dust. Besides pitchblende, the mines contain 

 silver, cobalt, arsenic, and nickel. Silicosis is as frequent as carcinoma, 

 but no relationship could be established between the two diseases. The 

 average time spent in mines before manifestations of carcinoma is thirteen 

 to seventeen years. The sites in the lung, the types and the biological 

 behavior of carcinoma are identical with those occurring in this organ 

 throughout the world (Behounek et al., 1937; Sikl, 1950). 



The literature on this miner's disease is too voluminous to be fully 

 reviewed. After the discovery of the carcinogenic properties of radio- 

 active substances, radon was blamed for the high incidence of lung cancer. 

 In a detailed investigation, Rajewsky et al. (1942) found that the radon 

 content of air in the mines of Schneeberg and Jachymov varied from 

 7 X 10~ 12 to 7 X 10~ 9 curie per liter. Measurements of the radioactive 

 content of lungs of miners gave radium equivalent values not different 

 from that of non-miners. Rajewsky et al. found an average radon con- 

 tent of the air of the mines to be 3 X 10~ 9 curie per liter and assumed a 

 permissible dose of 1 X 10 -8 to 1 X 10~ 9 curie per liter of air and con- 

 cluded that radon is possibly one of the causes of the lung cancer of the 

 miners. 



A similar permissible dose was established by Read and Mottram 

 (1939). Evans and Goodman (1940) arrived at a daily dose of 1 X 10~ n 

 curie per liter as follows: 1 jug of radium stored in the body will produce 

 1.1 X 10 _u curie of exhaled radon per liter. Three dial painters devel- 

 oped carcinoma of the ethmoids and antrum (Martland, personal com- 

 munication). One of these had 2 ng of stored radium in the body and 

 exhaled 2 X 10 -11 curie per liter. Typical air measurements in these 

 mines show ten to two hundred times this value. Krebs et al. (1930) 

 measured the body content of radium of eighteen persons who died with 

 no known exposure to radium and found a range of less than 1 X 10~ 9 to 

 4 X 10 -8 radium equivalent. Hursh and Gates (1950) made similar 

 measurements and arrived at one hundred times smaller values, which 



