Note: This series of stories broke national news about “popcorn lung,” a mysterious and deadly disease workers developed due to breathing artificial butter flavoring. The story continued to expand nationwide, resulting in a Congressional investigation, extensive national media coverage, and proposed new regulations.
This story was originally published in the St. Louis Post-Dispatch on April 4, 2004.
By Sara Shipley
MORGANTOWN, W.Va. — Federal health investigators warn that the threat of “popcorn workers’ lung” could go far beyond Midwestern microwave popcorn factories.
Investigators at the National Institute for Occupational Safety and Health say that workers who make a wide variety of products, from candy to snack cakes to potato chips, could be at risk of developing a severe lung disease associated with breathing butter flavoring vapors.
“We know that butter flavorings are very widely used,” said Dr. Gregory Wagner, director of the agency’s Division of Respiratory Disease Studies. “What we don’t know is how much injury has occurred.”
NIOSH first investigated an outbreak of lung disease associated with butter flavoring at a Missouri microwave popcorn factory nearly four years ago. At least eight former workers at the Gilster-Mary Lee plant in Jasper are reported to be on lung-transplant waiting lists. One woman became totally disabled after working around the flavoring for just eight months.
The agency now has documented cases of similar lung disease at four out of five other microwave popcorn plants it has investigated. Additional cases have been reported at three other popcorn factories and four manufacturers of butter flavoring.
Recently, NIOSH has received scattered reports of problems in other facilities — including a candymaker and a snack food plant — but the agency has been unable to confirm those cases so far.
According to NIOSH research, the threat is serious.
The agency’s animal studies have documented that chemicals in the butter flavoring cause rapid, severe damage to the airways of rats. One scientist, research physiologist Jeffrey Fedan, used the words “astonishingly grotesque” to describe the toxic effect of diacetyl, a key ingredient in the flavoring.
Vincent Castranova, chief of NIOSH’s pathology and physiology research branch, said that the effect of breathing butter flavoring vapors could be likened to inhaling acid.
“The airway response is the worst we’ve ever seen,” Castranova said. And that’s comparing it to a catalogue of notorious respiratory toxins such as asbestos and coal dust.
“When we say this is bad compared to what we’ve done before, we have a database of 20 years of exposure to different things that we compare it to,” Castranova said. “In layman’s terms, it ate away the coating of the airway.”
Guidelines are voluntary
Despite the severity and speed with which the butter flavoring chemicals appear to act, no regulations have been developed to prevent workers from breathing the mixture.
The Occupational Health and Safety Agency, the federal agency that enforces workplace safety standards, has focused instead on developing voluntary guidelines.
OSHA developed a brochure in October 2002 for the Popcorn Board, a Chicago-based industry group, to distribute to its members across the country, agency officials said.
The 10-page document recommends that microwave popcorn factories require workers to wear air-purifying respirators and goggles while working with flavoring chemicals. Other recommendations include instituting annual breathing tests for employees, installing adequate room ventilation and conducting air monitoring inside the plant.
A high-level OSHA official said the agency doesn’t need specific regulations on butter flavoring to protect worker safety. A general provision in the law requires employers to provide a safe workplace. Any facility that fails to carry out OSHA’s recommended controls and has a worker with flavoring-related lung disease could be subject to a citation, he said.
However, OSHA has not cited any of the companies where workers fell ill.
OSHA inspectors visited the Jasper popcorn plant in May 2000, after the workers had been reported ill, and found no violations. “We were satisfied with what we saw of the airborne exposure,” the official said in a recent interview.
John L. Henshaw, assistant secretary of labor for occupational safety and health, issued a statement saying that OSHA is committed to helping employers assure the health and safety of their workers.
“As soon as the (popcorn) issue arose, we began working with NIOSH and the popcorn manufacturers and their employees to do everything we can to ensure that the highest health and safety practices were implemented,” he said. “Guidance documents have been prepared and issued and we will continue to follow up to assure this issue is properly addressed.”
Frustrating limitations
Meanwhile, the small team of NIOSH investigators who cracked the popcorn cases is powerless to make any industry heed its warnings.
An arm of the federal Centers for Disease Control and Prevention, the agency has no regulatory authority. It can only conduct scientific studies, try to educate workers, and cajole employers to cooperate.
NIOSH is charged with investigating reported workplace dangers. Its state-of-the-art health effects laboratory examines potential hazards ranging from air pollution and workplace stress to injuries caused by machinery vibrations. Its field investigators are dispatched all over the country, sometimes on an emergency basis.
NIOSH can investigate work sites only where it has been invited by management, a union, a state health department or a group of three workers.
This limitation has proved frustrating in the case of butter flavoring.
The agency initially heard about the Missouri plant in the spring of 2000, after Dr. Allen Parmet, a Kansas City occupational health physician, contacted the Missouri Department of Health and Human Services. Parmet was concerned that eight workers from the same plant exhibited signs of the same strange lung disease.
The state agency referred the call to the Centers for Disease Control in Atlanta, which passed it on to NIOSH, said Dr. Kathleen Kreiss, chief of NIOSH’s respiratory field studies branch.
Kreiss said it took several months of phone tag to get state health officials to appreciate the seriousness of the reports. In August 2000, a new state epidemiologist, Dr. Eduardo Simeos, learned of the disease cluster and asked NIOSH for help.
Within weeks, a NIOSH team arrived at the plant, returning for a detailed health survey in September and October. One researcher drove a trailer full of X-ray equipment from Morgantown to Missouri to test the workers.
Initial breathing tests showed that 27 percent of workers had abnormal lung function, Kreiss said. “We knew right then that we had a major ongoing problem,” she said.
It was a problem that had gone unrecognized for a long time.
“Wife was persistent”
One of the first workers to fall ill, former housewife Angela Nally, was forced to quit work in 1994 when she learned she had just 20 percent of her lung capacity left. Five years would pass before Donna Woods surmised that something at the plant must be making her husband, Hal, grow weak and lose chunks of skin from his hands and feet. She made a round of phone calls in 1999 and figured out that several other former workers were sick, too.
Woods asked her son, attorney Jace Kentner, to investigate. Kentner and another lawyer rounded up medical records for eight workers who had been seen at clinics all over the country, having been diagnosed with asthma, emphysema and other illnesses.
That’s when Parmet diagnosed the eight as having bronchiolitis obliterans, an irreversible lung disease. The illness should be rare, but it appeared that the small town of Jasper was having an epidemic.
“The reason this came to light is, a worker’s wife was persistent,” Kreiss said. “Had it happened in Chicago, where people didn’t all go to the same doctor, and they didn’t see each other in the Wal-Mart parking lot struggling with shopping carts, it might never have been put together.”
Some plants resist
The process could have failed at any number of steps, had NIOSH not been perceptive and persistent in its work.
Kreiss was prepared for the job. She had worked at the premier lung hospital in the nation, National Jewish Medical and Research Center in Denver. And she had at her disposal a team of public health doctors, technicians and scientists who specialize in respiratory diseases.
The popcorn team visited the Missouri site eight times, but they didn’t stop there. In the summer of 2001, NIOSH started a national hunt to find out how far the problem went. A search of the Dun & Bradstreet business database turned up fewer than 100 plants nationwide that packaged unpopped popcorn, research industrial hygienist Greg Kullman said.
NIOSH met in the fall of 2001 with the American Popcorn Board and the Flavor and Extract Manufacturers Association, hoping to share information and to gain access to more plants.
Some companies, such as family-owned B.K. Heuermann Inc. in Nebraska, welcomed NIOSH. But others were less cooperative.
ConAgra Foods Inc., for example, let NIOSH conduct air sampling at its popcorn plant in Hamburg, Iowa, in 2001, but the company would not allow workers to be interviewed or tested, NIOSH medical officer Dr. Richard Kanwal said.
Later, ConAgra officials refused to let NIOSH visit its plant in Marion, Ohio, even after the agency learned in 2002 that a former worker had been diagnosed with bronchiolitis obliterans. Only after three employees signed a confidential request did investigators get to the scene.
The flavoring industry itself has been even less open. NIOSH investigators were allowed to walk through Bush Boake Allen’s now-defunct plant in Chicago. But the plant wasn’t making butter flavoring that day, and no tests were conducted, agency officials said.
“Despite our repeated offers to come and look and get some information we’ve not been invited to do any kind of survey at any flavoring plant,” Kanwal said. “We know from talking to a handful of workers that there’s a lot of open handling of a variety of different ingredients, some of which are highly irritating.”
In a statement issued last month, a spokesman for the flavoring manufacturers association said that the trade group held workshops on respiratory safety in 1997 and 2002 to educate its members.
“We take each report of a potential problem with the safety of flavors in manufacturing settings very seriously,” executive director Glenn Roberts said. “Fortunately, such incidents are very rare in our industry. Our goal is to understand what happened, and work with the best medical and workplace safety experts to recommend to our members and customers any additional workplace safety measures that may be needed.”
Testing chemicals
Another challenge is identifying the toxic agents in the complex butter flavoring mixture, which contains dozens of different chemicals. Tests from the Missouri plant showed that lung illnesses correlated with exposure to diacetyl, a yellowish substance that smells and tastes like butter.
In study published in 2002, rats exposed to butter flavoring vapors for six hours had severe damage to parts of their airways. In a new follow-up study, rats exposed to pure diacetyl vapors showed a similar result.
Veterinary pathologist Dr. Ann Hubbs presented some of the findings at the Society of Toxicology meeting in Baltimore last month. Cell damage occurred at levels of about 200 parts per million of diacetyl and above; at levels of 100 parts per million and below, those changes were not seen, Hubbs said.
The butter flavoring mixture affected a different part of the airways than diacetyl alone, Hubbs said. “The effects of mixtures often are not the same as any single component,” she said.
Hubbs said researchers plan to test other chemicals in the butter flavoring alone and in combination with diacetyl. The agency also plans to examine what happens when animals inhale short, intense bursts of the vapors, much as workers could on the job.
It could be years before all these studies are completed, paving the way for the creation of a workplace exposure limit. Based on its research, NIOSH can recommend a level of chemical exposure that should not be exceeded. OSHA, the regulatory agency, can adopt or modify the recommendation.
NIOSH Director Dr. John Howard said that the butter flavoring investigation is a top priority. To date, the agency has spent more than $2.5 million on the job.
“I think it’s a very pressing issue. NIOSH has put a tremendous amount of work into it,” Howard said.
NIOSH has mailed a detailed brochure to companies nationwide, warning them of the possible dangers and suggesting safety measures. The agency also plans to create a recommended exposure limit as soon as possible, Howard said.
OSHA also is preparing a safety and health information bulletin for nationwide distribution in a few months to food and fragrance manufacturers, a high-level official said.
“Even if you have a regulation, life isn’t all nirvana. You still have to get people to comply with your regulation,” Howard said. “So, at its core, it’s a sales job . . . That’s why we need to get that information out and acted on.”