Colloidal radioactive Au198 was injected intravenously into mice in large doses in an attempt to produce neoplasms of the reticuloendothelial cells. The Au198 became rapidly concentrated in these cells, over 80 per cent being retained in the liver.
Of eight mice receiving 475–1350 μc., seven died within 2 weeks with leukopenia, necrosis of the bone marrow, and hepatic degeneration, and one mouse surviving 9 months died with cirrhosis.
A dose of 44–160 μc. of Au198, estimated to deliver 850–3400 rep to the liver, caused no early deaths but produced chronic liver damage in 45–83 per cent and hepatomas in 10–26 per cent of mice injected.
In five of 31 livers examined microscopically, foci of ossification with marrow formation were noted.
The incidence of leukemia was not significantly altered, and neoplasms of reticuloendothelial cells were not produced by the colloidal Au198.
An increase in the incidence of pulmonary adenomas occurred in mice receiving both radioactive and nonradioactive colloidal gold.
Work performed under Contract No. W-7405-eng-26 for the Atomic Energy Commission.