OSHA = "Optional" Safety and Health Administration

Think twice before inhaling that buttery scent of microwave popcorn. The chemical used to create that flavor, diacetyl, has been found to cause severe lung damage in workers at microwave popcorn plants. The discovery, by the National Institute for Occupational Safety and Health, has been brought to the attention of the Occupational Safety and Health Administration (OSHA), but little has been done.

On diacetyl, [OSHA Head] Mr. Foulke said ''the science is murky'' on whether the additive causes bronchiolitis obliterans, the disease that has been called ''popcorn worker's lung...''

...Instead of regulations, Mr. Foulke and top officials at other agencies favor a ''voluntary compliance strategy,'' reaching agreements with industry associations and companies to police themselves.

Administration officials say such programs are less costly, allowing companies to hire more workers and keep consumer prices down. The number of voluntary agreements has grown in recent years, but they cover a fraction of the seven million work sites that OSHA oversees, or less than 1 percent of the work force. (emphasis mine)

Wikipedia's diacetyl entry only illustrates the lack of actual regulation coming from OSHA:

On July 26, 2006, the International Brotherhood of Teamsters and the United Food and Commercial Workers petitioned the U.S. Occupational Safety and Health Administration to promulgate an emergency temporary standard to protect workers from the deleterious health effects of inhaling diacetyl vapors. The petition was followed by a letter of support signed by more than thirty prominent scientists. The matter is under consideration.

There's some hope, as Congress has begun to reassert its oversight of OSHA, with hearings taking place two weeks ago. But holding hearings won't do much for some of the affected employees, one of whom was present at the hearing.

Among those who testified Tuesday was Eric Peoples, a former worker at the popcorn plant in Jasper, a small town 125 miles south of Kansas City. Once healthy, the 35-year-old Mr. Peoples has been told by doctors that he will need a double-lung transplant. (emphasis mine)

But hey, what's a couple lungs against 10 cent savings on my Jolly Time Blast O Butter?