Burger King's Halloween Whopper, which features a black bun made with A.1. Thick and Hearty Sauce, is reportedly turning customers' poop a striking green color.
"Not grass-green, but cartoon leprechaun-green,"
Gizmodo reported after an in-depth investigation.
As many began expressing their concerns online, to news outlets, and to the company itself, a Burger King spokesperson
told ABC News that the bun — the likely culprit — contains less than 1 percent food dye, and that the colored dyes are all FDA approved in the quantities used.
"The dyes that make the bun black are a combination of Yellow #6, Red #40, Caramel Color, and Blue #1," Gizmodo reported. "Blue #1 is also known as Brilliant Blue FCF. Brilliant Blue doesn’t absorb well in the intestines, so it often comes out in the poop — it just doesn’t come out blue."
The black burger, sometimes called the Goth Burger by fans, has been a regular promotion at Burger King's Japanese locations since 2013, however the U.S. version is formulated differently. The fast-food company has said in its promotional material that the Halloween Whopper will be available through October 31.
People concerned and amused by the recent fecal phenomenon began using the hashtag #greenpoop to express their concerns online.
"#GreenPoop is a real thing. Don't get to scared after eating it like I did,"
wrote one user.
"Maybe Burger King should bring the Black Whopper back for St. Patrick's Day? #GreenPoop,"
wrote another.
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