In the later days of World War II evidence was found in
Papua New Guinea of Japan's preparedness to use
chemical weapons, in the form of bombs loaded with a mixture of
mustard gas and
lewisite. British and American military planners became acutely aware of their lack of knowledge about the effects of such materials on soldiers in tropical areas. An Australian Chemical Warfare Research & Experimental Section was formed in 1942 and a top-secret facility established in Queensland near
Innisfail, and later at Gunyarra near
Proserpine, where a wide range of tests was performed by
British, American and Australian researchers on volunteers from Australian defence personnel, with nurses and laboratory assistants recruited from the
Australian Army Medical Women's Service. Initial tests proved that mustard gas was around four times as potent in tropical climates, with greatest aggravation to the skin occurring in the sweaty areas of the groin, buttocks, back of legs, neck and armpits. A large controlled environment stainless-steel gas chamber was designed by biochemists
J. W. Legge and (later Professor Sir)
Hugh Ennor to house volunteer subjects to ascertain the effectiveness of various materials and designs of protective clothing, during periods of physical exertion and after being subject to normal wear and tear. Other tests were conducted to determine the limits of endurance of soldiers in performing arduous tasks after bodily exposure to mustard gas. Gas masks or respirators were used to minimise inhalation of the gas. The determined resistance put up by Japanese soldiers against the Americans in their
assault on Tarawa in November 1943 prompted the US Army, which had sustained terrible losses in taking the island, to make plans for use of chemical weapons in further attacks of the kind. General
Douglas MacArthur was in favor of this approach, heavy naval bombardment having been unexpectedly ineffective at lowering the enemy's resistance.
North Brook Island, off the Queensland coast around 30 km east of
Cardwell, was prepared with various forms of
tunnel and foxhole to simulate the kind of emplacements used by the Japanese army, and goats tethered in these locations. Bombers then carpeted the island with mustard gas bombs and the following day unprotected Australian soldiers were landed on the island to assess the damage, and spent 12 hours there, suffering some lung damage and blisters where their bodies came into contact with contaminated foliage. The Allies never used gas against the enemy, as Japan surrendered following the dropping of atom bombs on Hiroshima and Nagasaki. The Chemical Warfare Unit was top secret and its very existence was denied for many years. Many of the volunteers had never served overseas, and so did not receive the monitoring and preferential health treatment accorded other ex-servicemen by the
Department of Veterans' Affairs. Mustard gas is known to damage DNA by
alkylation, and it has been suggested that the experiments were responsible for adverse long-term health effects on some of these volunteers. ==Recognition==