Dibenzo[a,l]pyrene (DB[a,l]P) is the most potent carcinogen among dibenzo[a]pyrenes. DB[a,l]P is more tumorigenic than 7,12-dimethylbenz[a]anthracene, DB[a,l]P 11,12-dihydrodiol, and 100–200 times more tumorigenic than benzo[a]pyrene. DB[a,l]P is also extremely toxic. Dose-response studies were conducted in the skin of female SENCAR mice by initiation-promotion to compare the tumorigenicity of DB[a,l]P to that of (±)-trans-DB[a,L]P-11,12-dihydrodiol, (±)-anti-DB[a,l]P diol epoxide (anti-DB[a,l]P and (±)-syn-DB[a,l]PDE. Mice were initiated with 12, 4 or 1.33 nmol of compound and promoted with tetradecanoyl phorbol acetate. DB[a,l]P at 12, 4 or 1.33 nmol induced 9.3, 7.1 or 5.2 tumors per mouse (t/m), respectively. DB[a,l]P-11,12-dihydrodiol induced 4.6, 4.3 or 2.8 t/m. Anti-DB[a,l]PDE resulted in 2.0, 0.7 or 0.7 t/m vs 1.8, 1.5 or 1.8 with syn-DB[a,l]PDE. The experiment confirms that DB[a,l]P is more potent than DB[a,l]P-11,12-dihydrodiol and shows that the two diol epoxides are less tumorigenic than their 11,12-dihydrodiol precursor. At low doses syn-DB[a,l]PDE is a stronger tumor initiator than its congener anti-DB[a,l]PDE.
- Tumorigenicity carcinogenicity dibenzo[a,l]pyrene
- dibenzo[a,l]pyrene metabolites
ASJC Scopus subject areas
- Polymers and Plastics
- Organic Chemistry
- Materials Chemistry