Tumorigenicity study of ferric citrate administered orally to mice.

Ferric citrate (FC) was orally administered at concentrations of 0.12 (maximum tolerated dose) or 0.06% in the drinking water to male and female B6C3F1 mice. Treatment was continued for 96 wk and the experiment was terminated at wk 100. There was no significant difference between treated and control groups in the tumour incidence or in the distribution of different types of tumour. Thus the long-term oral administration of FC to mice did not yield any evidence of chronic toxicity or tumorigenicity.