Heinz Ketchup and Mustard Gas 26 February 2008, Cervera de los Montes A4 (29,7 x 21,0 cm) Water color, acrylic color, pencil, color pencil, felt-tip pen on paper i Heinz is a U.S. brand of ketchup and other processed food. Mustard gas is a vesicant chemical warfare agent with the ability to form large blisters on exposed skin. Tags: tomato, ketchup, mustard gas 513 / 779