Paul Karason died on Monday, 15 years after he permanently turned blue. Karason's blueness made him into a minor celebrity in 2008 when he appeared on The Today Show.

Karason turned blue in the late 1990s after he started using a silver-based medication to treat his dermatitis. He also drank homemade collodial silver to treat the disease.

From NBC:

Silver has antibacterial properties and has been used to fight infection for thousands of years. But it went out of use when the far more effective penicillin was developed in the 1930s.

It continued to be used in some over-the-counter medicines until 1999, when the FDA banned it because it causes argyria, which is a result of the silver reacting with light the same way it does in photography. The silver collects in the skin and other organs and does not dissipate.

In addition to argyria (blue man disease), Karason suffered from a number of other health problems, including heart disease.

“He has been too ill to work for a while,” Karason's widow told NBC. “He didn't like to go out in public much – only when he thought he needed to, like to to go to the bank or to pick up tobacco.”

One reason why he didn't like going out in public, aside from being in terrible physical shape? People kept calling him “Papa Smurf.”

“That was a nickname he didn’t appreciate, depending on who said it,” his widow said. “If it was a kid who ran up to him saying ‘Papa Smurf,’ it would put a smile on his face. But if it was an adult, well ….”

Karason was 62.

[Image via Getty]