Microwave popcorn is one of America's favorite couchside snacks, but the butter flavor is raising questions about whether the crunchy treat could be dangerous to something other than the waist.
The chemical that helps create microwave popcorn's buttery aroma has been linked to serious health issues for workers who make the snack.
After working for 10 months at a St. Louis, Mo., flavoring company, 53-year-old Jerry Blaylock developed a life-threatening disease commonly called popcorn lung, which is linked to the chemical diacetyl. Now his once healthy lungs can hold just 45 percent of breathing capacity.
"I've got grandkids and we used to go to the zoo and amusement parks, but I no longer can do it," Blaylock said.
Experts believe when heated in a factory setting, diacetyl produces a toxic and potentially lethal gas. David Michaels, a former assistant secretary of energy, has been studying the issue for the last four years.
"Workers who mix the chemical as a liquid or powder breathe in small amounts of this chemical and it just devastates their lungs," Michaels said.
Now the comfort food is coming under scrutiny from those who want to be sure that ripping open a bag at home is not a hazard.
The Food and Drug Administration has never studied the effects of diacetyl, but Conagra Foods, which makes Orville Reddenbacher, told ABC News that it was confident that everyday use of its popcorn was safe for consumers.
"When it comes to diacetyl, the focus of concern is workplace exposure," the company said.
Connecticut state Rep. Rosa Delauro is asking the FDA to ban the chemical until it can be proven safe to consumers.
"We need to revoke its designation, test it further and protect the public health," Delauro said.
Flavoring manufacturers have paid more than $100 million as a result of suits brought by workers affected by popcorn lung. In California, a bill is being considered to ban its use in the state.
For now, the health risk at home remains up in the air. Though there's no proof that home exposure to diacetyl is toxic, Michaels said it might be wise for consumers to take precautions.
"I know in my home when we make microwave popcorn, we open it up under the vent over the stove so no one breathes the fumes," he said. "I'd like to see some branch of the federal government actually go out and test what's coming out of these bags."