Doping at the World Athletics Championships

Where an out-of-competition sample tests positive for a banned substance, any performances by the athlete after that date may also be annulled.

Samples are stored for future retesting, as improved methods over time may lead to previously unidentified cases of doping.

World champions to be banned include North American sprinters Ben Johnson, Marion Jones, Tim Montgomery and Kelli White.

Other prominent champions to have been banned include Russian middle-distance runner Mariya Savinova, steeplechaser Yuliya Zaripova and racewalker Olga Kaniskina.

[4] There has been an upward trend in the number of doping violations at the championships, with a peak of 50 athletes having had their performances annulled at the 2011 event, though it is assumed that this reflects improved detection rather than increased overall doping – an anonymous survey at that championships revealed over 30% of athletes had used banned substances during their career.

Ben Johnson 's disqualification in 1987 was the first time a world champion was stripped of their title for doping.
Marion Jones was stripped of three sprint medals for doping at the 2001 event
Three-time racewalk world champion Olga Kaniskina of Russia has been stripped of two of those titles for doping.
Mariya Savinova is one of many Russian athletes to be stripped for World Championships medals.
Zhanna Pintusevich-Block is one of two Ukrainians to be stripped of medals for doping at the event.