"Butylated hydroxytoluene (BHT), also known as butylhydroxytoluene, is a lipophilic organic compound, chemically a derivative of phenol, that is useful for its antioxidant properties. European and U.S. regulations allow small percentages to be used as a food additive. While there may be some dispute in BHT's use in the human diet, the chemical is widely used in industry wherever oxidation in fluids (e.g. fuel, oil) and other materials must be treated, and free radicals must be kept in check."
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