It may sound odd, but in America, your loaf of bread can contain ingredients with industrial applications – additives that also appear in things like yoga mats, pesticides, hair straighteners, explosives and petroleum products. Azodicarbonamide (ACA), a chemical that forms bubbles in foams and plastics like vinyl, is used to bleach and leaven dough – but when baked, it, too, has been linked to cancer in lab animals.
ref https://www.theguardian.com/us-news/2019/may/28/bread-additives-chemicals-us-toxic-america
the chemical is also used as a foaming agent in some plastic and vinyl products — namely, yoga mats
https://www.eater.com/2016/8/8/12403338/subway-yoga-mat-chemical-mcdonalds-burger-king-wendys
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