A food-derived carcinogen; metabolized by CYP1A2 and conjugated by N-acetyltransferase or sulfotransferase to a metabolite that reacts with DNA to form adducts; induces formation of single-base substitutions and exon deletions and increases cell death in vitro; increases incidence of squamous cell hyperplasias in the stomach of p53 knockout mice; increases hepatocellular lesions in female mice regardless of p53 status,