By David Michaels

The media has been buzzing (see here and here and here) about the announcement by the Pop Weaver Company that they will soon be marketing a butter flavored microwave popcorn that doesn’t use diacetyl in the butter flavor. As readers of this blog know, diacetyl (a component of artificial butter flavor) has been implicated in dozens of cases of terrible lung disease in workers who manufacture, mix and apply flavorings. (We’d like to know if the chemicals that have replaced diacetyl are safe – but that will be the subject of a later post).

We still don’t know if exposure to diacetyl at home is dangerous. A year ago, we asked the EPA to release the results of a study of the airborne materials that are released when bags of microwaved popcorn are opened, but the agency has refused, although the agency acknowledged it has given the results to the popcorn industry. Now, it appears that the still secret findings helped convince Pop Weaver to drop diacetyl.

Andrew Schneider, in the Seattle Post-Intelligencer, reports that

In part, it was the EPA’s study that led Pop Weaver to reformulate its flavoring without diacetyl, said Mike Weaver, chief executive officer of the 80-yearold family-owned company.

“We have to have good flavors, but at the same time we have to have ingredients that consumers feel good about and we were hearing too many concerns raised about diacetyl,” he said. “With these growing concerns and with EPA’s actions, we felt it was the prudent to stop using diacetyl and we have.”

In addition to Pop Weaver and six other private brands, the Indiana-based company also sells “Trail’s End” popcorn for the Boy Scouts of America. Five million boxes were sold last year, the Scouts said.

“Maybe the big food conglomerates don’t take diacetyl seriously, but we take it very, very seriously,” Weaver said. “We sell popcorn only. Without it, we’re out of business.”

The public does not know the results of the EPA study,

But the industry already knows what the EPA found, according to George Gray, the current head of the EPA’s office of Research and Development. He told the P-I that the popcorn industry was given the opportunity to review the final results before the study was submitted for publication.

Gray said there was nothing improper in allowing the industry to review the findings, saying it was necessary to convince industry that none of their confidential business information, such as what the flavoring agents are and the construction of the popping bag, was released to the public.

Further, Gray said the information could not be released to other public health professionals because it would prevent his scientists from getting their work published in peer-reviewed journals.

However, most prominent medical and scientific journals said that exceptions are always made.

We’re not going to punish researchers for disclosing information that is of vital interest to the public health,” said Karen Pedersen, manager of media relations for The New England Journal of Medicine.

ConAgra, the manufacturer of the Orville Redenbacher, has been collecting its own data on home exposure levels. Last May, we published information concerning ConAgra’s own testing program. Schneider followed up on this, as well:

ConAgra Foods, which says it is the largest supplier of the 3 billion bags of microwave popcorn sold worldwide each year, declined to comment on Pop Weaver’s action.

However, in interviews earlier this month, corporate spokeswoman Stephanie Childs told the Seattle P-I that ConAgra has been “looking at the diacetyl issue very seriously over the years.”

Scientists and consultants for ConAgra, whose brands include Orville Redenbacher and Act II, found in 2004 that diacetyl was released when freshly popped bags of corn were opened. However, Childs said that the company saw no need to change its flavorings.

“Based on all the information we have available to us, we are confident the everyday, normal use of butter-flavored microwave popcorn in the home is safe,” she said.

But in a November 2004 letter to the EPA, Patricia Verduin, ConAgra’s senior vice president for product quality, wrote: “We believe it is imperative that the health and safety of this product be assured to the extent possible within the very near future.” In the letter to the then-head of the EPA’s Office of Research and Development, she said that ConAgra had developed a “Consumer Exposure Risk Index” to address potential health concerns from material released when the bag of popped corn is opened.

ConAgra declined to discuss what level of risk it documented to consumers from vapors from diacetyl, other flavoring ingredients or the bag itself.

“We shared that information with EPA on a confidential basis and we look to them for the next step,” Childs said. “We, as well as the rest of the world, are awaiting the release of EPA’s study.”

It is possible that the EPA study will show that diacetyl exposures at home are very low. I certainly hope so. But the EPA should stop stone-walling and simply release the study.

David Michaels heads the Project on Scientific Knowledge and Public Policy (SKAPP) and is Professor and Associate Chairman in the Department of Environmental and Occupational Health, the George Washington University School of Public Health and Health Services.