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Seven-time Olympic medal winner Penny Oleksiak has withdrawn from the upcoming world aquatics championships due to being in a whereabouts case with World Aquatics.Adrian Wyld/The Canadian Press

Canada’s Penny Oleksiak has withdrawn from the world aquatics championships due to being in a whereabouts case with World Aquatics, she announced on social media Friday.

The 25-year-old Toronto native said “it does not involve any banned substance” and “I am and always have been a clean athlete and will be making no further comment at this time.”

The world championships are set to begin July 11 and end Aug. 3 in Singapore.

Oleksiak received support of her decision from Swimming Canada CEO Suzanne Paulins, who said the organization believes Oleksiak “is a clean athlete who made an administrative mistake,” in a statement on social media.

Paulins did, however, say it was “disappointing news.”

Paulins said athletes are responsible for completing whereabouts and submitting filings on time to comply with anti-doping rules to avoid sanctions.

Oleksiak is a seven-time Olympic medalist and nine-time world championship medalist.