What's in a McRib? Stuff Used to Make Gym Mats

McDonald's McRib sandwich is back for a limited time around the country. You'd think that a BBQ pork sandwich would have just a few ingredients -- like pork, a bun, and sauce, right? Think again.

The McRib contains 70 ingredients! (There are 34 ingredients just in the bun!)

TIME reports on some of the ingredient highlights, including azodicarbonamide, which is used for gym mats:
Azodicarbonamide, a flour-bleaching agent that is most commonly used in the manufacture of foamed plastics like in gym mats and the soles of shoes, is found in the McRib bun. The compound is banned in Europe and Australia as a food additive. (England's Health and Safety Executive classified it as a "respiratory sensitizer" that potentially contributes to asthma through occupational exposure.) The U.S. limits azodicarbonamide to 45 parts per million in commercial flour products, based on analysis of lab testing.
How on earth are ingredients like this allowed to be used for food?

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