Induction of subcutaneous tumors in rats by 3,7- and 3,9- dinitrofluoranthene

Abstract
Two dinitrofluoranthenes (DNFs) derived from 3-nitrofluoranthene were purified to over 99%, and tested for tumorigenicity in F344/DuCrj male rats. Rats were inoculated s.c. with 0.05 mg 3,7- or 3,9-DNF twice a week for 10 weeks. All 21 rats given 3,7-DNF and 10 of 11 rats (91%) given 3,9-DNF developed tumors at the injection site by 48 weeks after the first injection. Twenty of the 21 tumors induced by 3,7-DNF and seven of the 10 tumors induced by 3,9-DNF were classified as malignant fibrous histiocytoma, but one tumor in the 3,7-DNF-treated group and three tumors induced by 3,9-DNF showed typical features of rhabdomyosarcoma. The first tumors in 3,9-DNF-treated rats appeared on day 88 (on day average 117), 10 weeks earlier than in 3,7-DNF-treated ones (on day average 186).