B(a)P administration to mice caused an increase in lung-specific tumour marker and lipid peroxides (LPO), serum marker enzymes, gamma-glutamyl transpeptidase (GGT), 5′nucleotidase (5′ND), lactate dehydrogenase (LDH), carcinoembryonic antigen (CEA), and aryl hydrocarbon hydroxylase (AHH), along with a concurrent reduced in the levels of tissue antioxidants such as superoxide dismutase (SOD), Vitamins E and C, peroxidase (gpx), reduced glutathione (GSH), and glutathione catalase (CAT). The gene discussed is CEACAM5; the disease is neoplasm.