Canadian swimmer Penny Oleksiak, the country’s most decorated Olympian with seven medals, has withdrawn from the World Aquatics Championships scheduled for 11 July–3 August in Singapore after becoming the subject of a whereabouts case under World Aquatics’ anti-doping regulations. Oleksiak, 25, said the matter "does not involve any banned substance," insisting she "is and always has been a clean athlete." Under the rules, competitors must update their location daily for possible out-of-competition testing; three filing failures within 12 months can trigger sanctions. Swimming Canada said Oleksiak has not been sanctioned but decided to withdraw voluntarily to protect team results should an anti-doping violation later be confirmed. Chief executive Suzanne Paulins called the lapse "an administrative mistake" and reiterated the federation’s commitment to strict compliance with World Aquatics and World Anti-Doping Agency requirements.