Disclosed are methods, materials, apparatus and systems for removing or suppressing ambient levels of reactive gas contaminants, particularly acidic gases, using particles of zeolite, sepiolite or other suitable carrier material impregnated with at least one treatment compound selected to react with the acidic gas(es). The methods involve contacting a contaminated gas stream with the impregnated carrier materials whereby at least a portion of the reactive gases contacts the treatment compound and reacts, thereby consuming the reactive gas molecules.