Benzo[a]pyrene is a polycyclic aromatic hydrocarbon contaminant that acts as a chemical carcinogen in cancer experimental models.

Terephthalic acid, a raw material for polyethylene terephthalate (PET) production, is one of the most important chemicals in petrochemical industry.

7,12-Dimethylbenz[a]anthracene (DMBA) is a polycyclic aromatic hydrocarbon (PAH) that has been found in tobacco smoke and diesel exhaust and has carcinogenic activity. It undergoes metabolic activation by numerous enzymes, including the cytochrome P450 (CYP450) isoform CYP1B1, as well as microsomal epoxide hydrolase (mEH), producing a variety of reactive metabolites that form DNA adducts in vivo, and it has been commonly used to induce tumor formation in various rodent models. DMBA increases proliferation and migration of, and induces epithelial-to-mesenchymal transition (EMT) in, MCF-10A breast cancer cells when used at a concentration of 5 µM. It also has immunosuppressant activity, inhibiting proliferation of isolated mouse splenic B- and T cells stimulated ex vivo with LPS or concanavalin A, respectively, when administered at doses of 50 and 100 mg/kg. Intragastric administration of DMBA (20 mg/animal) induces formation of mammary gland tumors in rats.6 DMBA (50 µg/animal), in combination with phorbol 12-myristate 13-acetate, initiates papilloma formation in a rat two-stage model of skin carcinogenesis.