With regards to the Dichoroethyl Sulphide (Mustard Gas) issue, the United States at the time, were not signatories to the Geneva Convention restricting the use of Chemical Weapons...
As such, the U.S Army Chemical Corp were responsible, at the time, for the transportation of U.S Chemical weapons, most notably, mortar bombs for the 4.7inch "Goon Gun" Mortar...
Said rounds were reportedly transported near to the battlefield, ready for use...
However, as the knowledge of the "Goon Gun", & it's related ordanance was classified, most U.S Army personell did'nt know of this weapons existance...
The result, of this policy, was reportedly 1000 U.S servicemen were either killed, or very badly wounded as a result of the Bari Incident, in which a Luftwaffe air raid on Bari Harbour, in response to a somewhat bombastic radio speech, by a high ranking Allied Officer caused the cargo of a U.S freighter, which included Goon Gun rounds, to "cook off", causing mustard gas to enter the sea & air...