Greek javelin thrower Ioannis Kyriazis has been given a four-year doping ban by the Athletics Integrity Unit (AIU).
The 24-year-old, who finished sixth at the 2017 World Athletics Championships in London, tested positive for prohibited substance ligandrol.
The substance can stimulate muscle growth like anabolic steroids.
Kyriazis has been banned until May 2023.
He failed a doping test after an out-of-competition sample was taken in College Station in Texas in April 2019.
At the disciplinary hearing in London, a claim was dismissed that Kyriazis was accidentally contaminated by a prohibited substance used by a housemate for bodybuilding.
The AIU has also confirmed a provisional suspension against javelin thrower Martina Ratej of Slovenia for the presence of prohibited substance clostebol.
It is based on the re-testing of a sample taken at the London 2012 Olympic Games, where she finished seventh.
The outcome of the case is pending International Olympic Committee proceedings.
Another athlete handed a provisional suspension by the AIU is Bahraini long-distance runner Hassan Chani.
A charge has been issued in the Athlete Biological Passport case, which relates to the use of a prohibited substance/method.
The AIU was founded by the International Association of Athletics Federations, now known as World Athletics, in April 2017 to combat doping in the sport.