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From NPR News, this is ALL THINGS CONSIDERED. I'm Audie Cornish.
A few weeks back, the sandwich chain Subway got a lot of attention when it announced its plans to remove a food additive from its bread. The announcement was, in part, a response to an online petition that pointed out this same additive was used in, of all things, the manufacture of yoga mats. The story went viral and since then, as NPR's Allison Aubrey reports, it just won't go away.
ALLISON AUBREY, BYLINE: So the food additive under the spotlight is called azodicarbonamide. It's found in hundreds of baked goods, from Pillsbury Dinner Rolls to Wonder Bread. Commercial bakers love it because it helps keep bread a nice, spongy texture; just as it keeps your yoga mat cushiony. And according to the creator of the blog Food Babe, the yoga mat association is just one concern. Her online petition pointed to links to respiratory problems, asthma, possibly even cancer. And given this list, who wouldn't be concerned?
Twenty-something Justin Pagano, who came across the petition just as the news of it was going viral, says there was definitely a knee-jerk reaction.
JUSTIN PAGANO: Yes, yes, I'll sign your petition. Sign me up right away. This just sounds so terrible.
AUBREY: But Justin says he was skeptical. If this food additive was so bad, he wanted to see the evidence. As a science major in college, he knew his way around scholarly publications. So he decided to do some digging.
PAGANO: I said, you know, do I know anything about this compound? Have I read about it before? And I just started picking it apart.
AUBREY: And this is what he found: Despite the fact that azodicarbonamide is not approved for use in European countries, there are no studies showing it causes asthma in people who eat bread made with it. The reports about breathing problems came from factory workers who have breathed in high levels of the compound.
He also looked for evidence that azodicarbonamide, or its breakdown products, relate to cancer. He says he found a few studies. Mice were exposed to high doses, nothing close to the tiny exposures people get from bread. Now, Justin has no connection to the bread industry. He just considers himself a kind of concerned citizen scientist. And his conclusion?
PAGANO: It's really hard to say, or conclude, that this is bad for you.
AUBREY: And the Food and Drug Administration seems to agree. They reviewed the evidence on this compound years ago, and decided that small amounts in bread were fine. They set a limit of 45 parts per million, and food scientist Kantha Shelke says this makes sense.
KANTHA SHELKE: Forty-five parts per million is very, very, very small. So azodicarbonamide should not be that scary.
AUBREY: But doesn't it just feel wrong that an ingredient found in our bread is also used to make our yoga mats and other, plastic stuff? That's what set off so many headlines. But food scientists say, wait a minute. Think about Sheetrock or drywall. It contains calcium sulfate, or gypsum, which is also used as a food additive. In fact, it's used to make tofu.
So ingredients do cross over, and that doesn't mean they're dangerous. But Kantha Shelke says in an era when social media can whip up a frenzy of concern, regardless of the science, food companies are becoming quick to act.
SHELKE: Nobody wants to be associated with anything that can be remotely considered harmful.
AUBREY: And this explains why: In the wake of Subway's announcement to yank the compound from its bread, other manufacturers have done the same. David Andrews, a scientist with the Environmental Working Group, argues it's the right move.
DAVID ANDREWS: Really, this is an unnecessary chemical that's added to bread.
AUBREY: And as bread manufacturers in Europe already know, there are viable alternatives. One option is ascorbic acid, a form of vitamin C.
Allison Aubrey, NPR News.