The production of cancer by pure hydrocarbons —Part III

Abstract

Abstract The carcinogenic properties of 1: 2: 5: 6-dibenzanthracene, 5: 6-cyclo-penteno-1: 2-benzanthracene and some closely related compounds have already been described (Part I, Cook, Hieger, Kennaway and Mayneord, 1932; Part II, Cook, 1932, a; Burrows, Hieger and Kennaway, 1932; Burrows, 1932 and 1933; Barry and Cook, 1934). The present com­munication records the results of a systematic examination for carcino­genic activity of tetracyclic and pentacyclic aromatic hydrocarbons, and also deals with the extension of this work along lines suggested by the results obtained. Technique (1) Tests for the production of cancer of the skin were carried out by applying the substance in solution to the interscapular region of mice twice weekly. In the great majority of cases the compound was applied in benzene (0·3 gm in 100 cc), whether this gave a saturated solution or not. The advantages and disadvantages of this method have been discussed in an earlier paper (Part I). Any other concentrations or solvents used are stated in the tables below. The results are shown in Tables I-IX.