The old Japanese army developed several chemical warfare agents on Ohkuno Island in Seto inland sea, Hiroshima Japan, during the period between 1919 and 1944. These chemical agents including yperite (mustard; irritating agent), lewisite (irritating agent), diphenylchloroarsine (DA; vomiting agent), diphenylcyanoarsine (DC; vomiting agent) and other poisonous gases were manufactured to be used i...