The tryptophan disaster in the end of the 1980′s and beginning of 1990′s killed 37 and permanently disabled 1,500 people in the United States in a disease called eosonophil myalgia syndrome (EMS).

It was caused by one or more extremely poisonous substances present in a tryptophan food supplement, which was produced by genetically engineered bacteria at the Japanese firm Showa Denko.

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