Fast food franchise Subway has said that its bread sold in China does not contain the chemical that is being phased out in the United States market.
In a statement posted on its website, Subway said azodicarbonamide, a chemical compound also used for manufacturing plastic articles, is not used in its bread sold at Subway restaurants in China, Singapore and Malaysia.
The food chain said it is in the process of removing the ingredient from bread sold in the US, "even though it is fully approved by US authorities".
Vani Hari, a blogger who runs food and health website FoodBabe.com, launched a online petition on Feb 4 calling for Subway to phase out the chemical ingredient, which Hari said being "used to make yoga mats and shoe rubber" and "has been banned all over the world".
Hari said she has written about Subway ingredients several times since 2012. Her online petition on Feb 4 became an instant hit online and received more than 78,000 signatures as of Feb 7.
CNN reported that grocery store bread and restaurant bread in the US also contain the chemical. Other major fast food chains have products with the ingredient too, including McDonald's, Starbucks and Arby's.
Hari said she focused on Subway because of its healthy image. She also noted that the food chain only used the chemical ingredient in North America.
"This is not eating fresh!" Hari said in the petition.
Subway, which is owned and operated by Doctor's Associates Inc, says it has more than 41,200 locations worldwide.