Elaine Benes loved poppy seed muffins. That is, until she failed a drug test at work for opium. That's right. As Peterman said, "White Lotus. Yam-yam. Shanghai-Sally." Elaine did not lose her job, but she was not allowed to accompany Peterman on his trip to Africa.

This iconic Seinfeld episode led many to wonder whether eating too many poppy seeds could actually affect someone's drug test and result in a false-positive for opioid use. A 2003 peer-reviewed scientific study confirmed the Seinfeld thesis, finding that eating poppy seeds could be detectible on some drug tests.

A recent incident reported by the Washington Post reveals that poppy seed false positives can occur in the real world as well. As the Post reported, a woman ate a poppy seed bagel (which is well-known to be superior to a poppy seed muffin) the morning she went into labor, and she later tested positive for opiates. The false-positive resulted in her daughter having to stay in the hospital for several days for monitoring.

Could this affect work place drug testing? Can an employee assert the Seinfeld Defense?

Not likely. The U.S. Department of Health and Human Services (HHS) in 1998 raised the recommended level needed to test positive for opiates from 300 ng/mL to 2000 ng/mL. As reported by the Post, one would need to eat more than three large poppy seed bagels to fail under the higher level. The woman in the Post story failed because some hospitals, including hers, did not adopt the higher test levels.

While a false-positive drug test for eating too many poppy seeds seems far-fetched, companies with drug testing programs should be reminded that it is a remote—a very remote—possibility, especially if the test they use has a lower threshold for a positive opiate result. And if an employee claims the Seinfeld Defense, they may also be familiar with another bit of the show's wisdom: "Jerry, just remember, it's not a lie if you believe it."

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