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Remember back in February when Subway announced that its bread would no longer be made with a chemical foaming agent also found in yoga mats and shoe rubber? Their comments made a splash for two reasons: first, because it marked the success of a consumer-driven campaign to get the company to reform its practices; and second, because most of us were surprised to find out that the chemical was being used in the first place.

The chemical, azodicarbonamide (also known as ADA), has been banned in Europe and Australia, but is FDA-approved so long as its presence is limited to fewer than 2.05 grams per 100 pounds of flour or 45 parts per million. The World Health Organization links it to respiratory illnesses, allergies and asthma in workers handling large volumes of it. “When you look at the ingredients, if you can’t spell it or pronounce it, you probably shouldn’t eat it,” Vani Hari, the activist blogger who started the Subway campaign, said.

But it isn’t just Subway – as the company pointed out, it can still be found in products at Starbuck’s, Wendy’s, McDonald’s, Arby’s, Burger King, and Dunkin Donuts.  And according to a report released by the Environmental Working Group, it can still be found in nearly 500 food products on grocery store shelves.

The  list covers 130 brands of breads, buns, snacks, pastries and pre-made sandwiches, from America’s Choice to Wonder bread. As EWG  explains, it’s commonly used as a “dough conditioner” to make bread both puffier and more able to withstand shipping and storage.