Abstract: A method and solution are provided for reducing air-polluting odors emanating from organic waste products produced by metabolic processes and from organic industrial wastes, including effluents, sewage sludges, and the like, the method comprising contacting said wastes with an aqueous acid solution containing a water-soluble oxidizing agent selected from the group consisting of nitrates, chlorates and permanganates of ammonia and alkali metals, and also a precipitating agent selected from the group consisting of water-soluble ferric and ferrous compounds.