Fighting Mustard Gas with SAG Paste

American Soldier Suffering Severe External  Mustard Gas Burns

Of the chemical agents employed by the Germans against the Allies, mustard gas was responsible for 39 percent of AEF gas casualties. Once mustard gas made contact with the skin, it destroyed tissue as long as it remained, doing damage several hours before the first symptoms appeared. To combat this persistent blister agent, the Gas Service made available to line units an ointment called SAG paste (a term coined by reversing the letters of "gas") to protect exposed flesh. SAG paste came in a 3.5cm by 16cm collapsible tube and became a standard-issue item for the prevention and treatment of mustard burns. According to one veteran, it looked like and had the consistency of "carbolated vaseline". Doughboys who entered a mustard-contaminated area or who anticipated a shelling of Yellow Cross smeared their bodies with the ointment. 

An Interesting 1921 War Surplus Advertisement that Indicates While Different Manufacturers Varied the Formula, Zinc Was Always the Active Ingredient for SAG Paste

It proved very effective, a medic in the 35th Division noted, if used in time. However, it was uncomfortable because it caked when the men perspired and rubbed off on clothing when a soldier engaged in any physical activity. The paste also presented a danger — if not removed after exposure to gas it eventually absorbed the mustard agent without neutralizing it, which meant that the agent ultimately came into contact with the skin. There were other uses for the paste; medics, for example, found it to be effective in soothing mustard burns by blocking the oxygen to the contaminated area. Enterprising men in the trenches found it extremely effective in exterminating "cooties", the Doughboy slang for body lice.

Chemical Warfare in World War I:
The American Experience, 1917-1918
by MAJ. Charles E. Heller, USAR