American judoka Nicholas Delpopolo has been disqualified from the Olympics after admitting consuming food spiked with marijuana, the International Olympic Committee (IOC) says.
Delpopolo, who fought in the men's 73kg category of the judo competition and finished seventh, failed a drugs test carried out on July 30 which showed traces of marijuana in his system.
The IOC said in a statement the 23-year-old had accepted his disqualification after admitting his offence in a statement.
"The athlete explained his positive test was caused by his inadvertent consumption of food (prior to his leaving for the London Olympic Games) that he did not realize had been baked with marijuana," the IOC said.
"The athlete apologised to the USOC (United States Olympic Committee), his team-mates and his fans and indicated that he was embarrassed by his mistake."
Delpopolo had waived his right to a hearing in the case, the IOC said, and was due to return home to the United States on August 7.
Delpopolo's disqualification was a bitterly disappointing end for the American, who spent the early years of his life in an orphanage in Montenegro before being adopted by an American couple as a baby.