A Comparison of the Action of Some Polycyclic Aromatic Hydrocarbons in Producing Tumours of Connective Tissue

Abstract

Introduction The object of the work described here was to investigate the production of tumours of connective tissue by polycyclic hydrocarbons. An earlier paper from this Institute recorded a series of spindle-celled tumours in animals which had received injections of 1:2:5:6-dibenzanthracene (1). In the later experiments recorded below the results obtained with this compound were confirmed, and the action of two other hydrocarbons (5:6-cyclo-penteno-1:2-benzanthracene (2, 3), chrysene), and of the medium (lard) used for injection, was examined. Technique The hydrocarbons were dissolved (2 mg. in 1 c.c.) in the fraction of lard which is liquid at 37° by heating the containing vessel in boiling water; no higher temperature was used at any stage, and the injection needle was not passed through a flame. The material at 37° was injected sub cutem in the groin of rats and mice (at first 1 c.c. in rats and 0.5 c.c. in mice weekly; later 3 c.c. in rats and 1 c.c. in mice at longer intervals, regulated by the rate of disappearance of the substance).