Professor Pierre Cornillot, President of Paris Nord University, said the gas is also a strong antiseptic, and was used to heal soldiers' wounds in World War One.

Allingham is one of only two surviving World War one veterans in the United Kingdom and the last surviving founder member of the Royal Air Force, according to British media.

Britain has always been the principal source—ninety percent of Australians are of British descent, and Britain has provided one million migrants since the Second World War.