The author's firm took out a patent on the use of ethylene oxide for sterilizing spices and other commodities in 1936. Most of the requirements for most materials are met by ethylene oxide: effectiveness against all microorganisms and spores at a low dosage; the possibility of the commodity remaining within its normal packaging material (unless this is airtight) absence of toxicological risks for the consumer; absence of functional or physical effects in or on the product, e.g., color texture. Two types of process are described, that using 100% ethylene oxide, and that using 12/88, with 88% freon gas. The gas is both highly poisonous and explosive, so special installations are required with only highly trained personnel doing the work. Special attention is paid to the degassing of the substrates. (Editor's note: More recent work has implicated ethylene oxide as a carcinogen and has focused on the persistence of the toxic chemical ethylene chlorohydrin formed from the reaction of ethylene oxide and chlorides on or in artifacts. Ethylene oxide fumigation is currently banned in the United States.)