In the United States the incidence of prostate cancer is highest in African American (AA) men but significantly lower in Asians Americans; AA men are considered high risk for prostate cancer and they have the highest prostate cancer incidence in the world.Exposure to high level of environmental contaminants like the polycyclic aromatic hydrocarbon has been one of the suspects in prostate cancer high incidence in AA men.Development of a unique transgenic mouse model in Matusik Laboratory, the Lady Mouse (12T-7s) which develops prostatic intraepithelial neoplasm (PIN) to High Grade PIN to adenocarcinoma over a reproducible time frame has provided an animal model for testing the hypothesis that exposure to Benzo(a)pyrene [B(a)P] a protypical polycyclic aromatic hydrocarbon affect the prostate specific genes in cancer formation of the prostate.Exposure to Benzo(a)Pyrene, showed significant high levels of B(a)P metabolites in the prostate gland.Neotag (NT1) and Neotag (NT2) cell lines derived from Lady mouse prostate when exposed to [B(a)P] in culture have also shown for the first time significant level of Benzo(a)Pyrene metabolites in cultures of both the Neotag Ⅰ & Ⅱ prostate cell lines.The dihydrodiol group of metabolites (BaP 4,5; 7,8-; 9,10 diols) was detected in prostate in vivo experiments while the hydroxyl (3-OHand 9-OH) were not detected.In vitro exposure with Neotag cell lines showed the presence of both the dihydrodiol and the hydroxyl B(a)P metabolites.Studies on these metabolites on prostate specific genes are in progress.