 Consumption of large quantities by cattle leads to an acute poisoning syndrome with symptoms of bone marrow depletion, while at lower levels of long-term consumption it acts as a cancer cofactor.Carcinogenesis is a multistep process; tumours also contain activated Ras, as well as mutation or downregulation of the tumour suppressor genes "p53" in alimentary tract cancers and "fragile histidine tetrads" ("FHIT") in urinary bladder cancers.Viral particles are not produced in either alimentary tract or urinary bladder tumours.