CHEMICALS: Subway to remove compound found in yoga mats from its bread Published: Thursday, February 6, 2014 Subway, the world's largest sandwich chain, this week said it will stop using a chemical found in yoga mats in its bread. Please subscribe to Greenwire to read the full story. Username: Password: Forgot your access codes? Recover them. Not a subscriber? Sign up for a trial. Ready to subscribe? Click here.