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(CNN) – Food blogger Vani Hari wanted to know if she was actually "eating fresh" when comping down on Subway sandwiches. But she was in for a rude awakening.
"What I found out was horrifying," Hari said in an interview with CNN's "The Lead with Jake Tapper.
Hari found some varieties of Subway's bread contain the chemical azodicarbonamide. Besides bread, the chemical is also found in yoga mats and shoe soles to add elasticity.
"I found out the World Health Organization has linked it to lung problems, skin irritation, and eye irritation. And as well as finding the study that shows when it's heated, it can reduce down into compounds that are carcinogenic, things that cause cancer," said Hari.
Hari wrote about her findings back in 2012, and started a petition to pressure Subway to stop using what she says is a dangerous chemical. She even filmed a video of herself eating a yoga mat to drive home the point.
And today, Subway announced it is parting ways with azodicarbonamide.
"We are already in the process of removing azodicarbonamide as part of our bread improvement efforts despite the fact that it is (a) USDA and FDA approved ingredient," Subway said in a statement Thursday. "The complete conversion to have this product out of the bread will be done soon."
After First Lady Michelle Obama announced she was endorsing Subway last month, Hari says she contacted Subway, again, to ask the company about this ingredient.
"I thought, for goodness sake, they must be taking out this ingredient. The person I spoke to had no idea about this ingredient," said Hari.
It is a common ingredient in the United States, one which the Food and Drug Administration and U.S. Department of Agriculture say is safe to use.
Critics of Hari say she does not have a degree, or the expertise to address this particular issue.
"Well, let's just use commonsense here. Do we really need to be eating plastic in our bread?" said Hari. "This is something that almost every country around the world has banned... This is something that we're not supposed to be eating."
The chemical is banned from being used in dough in Europe and Australia.
"It's the same stuff that makes the foam in an air mat. This is definitely not real food," said Hari. "If it's not real food and there are these risks, I don't see the harm in asking Subway to take these ingredients out."
But there is thus far no evidence that any one has been hurt from the chemical in Subway's bread.
"The problem why there hasn't been any evidence is because there hasn't been any long-term human studies. The Centers of Science and Public Interest just came out with a statement saying the chemical compound does release other compounds that are carcinogenic. And there is a small cancer risk," said Hari.
"The FDA should not allow this ingredient in our food. And especially a company like Subway, who has already reformulated its products for everyone across the globe, already selling this sandwich without the ingredient, and they're selling us this ingredient? This is not fair," said Hari.
Hari said Subway reached out to her yesterday, to apologize for not responding to her earlier queries, and to let her know it planned to remove this ingredient from its breads soon.
"I asked for a timeline, and I asked to meet with them, and find out what ingredients are they going to be using. Are they going to actually be making bread now, is it going to be fresh?" said the food blogger.
"I'd really like to know, and I hope Subway responds," said Hari.