Domestic TerrorismMustard Gas January 2008, Cervera de los Montes Ø 9.5 x cm Adhesive label on plastic bottle i Mustard gas is a vesicant chemical warfare agent with the ability to form large blisters on exposed skin. The bottle is a 1.5 liter milk container of Hacendado, Spanish supermarket chain Mercadona's private brand. 11 / 12