When Irma Ortiz walked into Dr. Phil Harber's Los Angeles office last year, it was the end of a frustrating medical journey. For years, doctors said she had asthma. Or bronchitis. They prescribed medicine, then sent her on her way. She kept coughing. She got weaker. By December 2005, the 45-year-old woman who could once lift 50-pound boxes without breaking a sweat could work no more.

The next spring, Harber, chief of UCLA's division of occupational and environmental medicine, confirmed Ortiz had bronchiolitis obliterans - a rare, debilitating lung disease. That came 18 months after Harber detected the same disease in a man in his late 20s who worked at another California flavoring plant and couldn't walk 10 to 15 feet without losing his breath. Both handled diacetyl. And both, Harber says, had lost about 70 percent of their lung capacity.

What disturbs the doctor is Ortiz was being exposed to diacetyl even though there were reports in medical journals, National Institute for Occupational Safety and Health findings and case histories of sick microwave popcorn plant workers in Missouri. "There was sufficient information and sufficient time so controls should have been in place," he says. "Her serious illness never should have happened."

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