CJ Ujah has been banned for 22 months after he failed a drugs test at last summer’s Olympic Games.
Britain lost their 4x100m silver medal from Tokyo when Ujah tested positive for two prohibited substances.
However, Ujah, 28, was found not to have breached the sport’s doping rules on purpose.
Ujah was tested on the day of the final in Tokyo – August 6 – and his sample contained the prohibited substances ostarine and S-23.
He will be allowed to return to competition when his backdated ban ends in June of next year.
A statement read: “The Athletics Intergrity Unit (AIU) and World Anti-Doping Agency WADA were satisfied that the sprinter’s anti-doping rule violation (ADRV) was not intentional as a result of his ingestion of a contaminated supplement and the applicable two-year period of ineligibility was reduced by two months on account of how promptly he admitted the violation.”
AIU head Brett Clothier added: “In this case, after a thorough examination of the facts, we were satisfied that Mr Ujah did indeed ingest a contaminated supplement, but he was unable to demonstrate that he was entitled to any reduction in the applicable period of ineligibility based on his level of fault.
“Taking supplements is risky for athletes as they can be contaminated or even adulterated with prohibited substances. Athletes owe it to their fellow competitors to be 100 per cent certain before putting anything into their body. If there’s the slightest doubt, leave it out.”
Ujah was part of the British quartet which missed out on gold to Italy in Tokyo by 0.01 seconds.
Ujah said he would “regret for the rest of his life” the pain his case had inflicted on his team-mates Zharnel Hughes, Nethaneel Mitchell-Blake and Richard Kilty after they were forced to give up their silver medals.
Speaking earlier this year, Kilty said he would never be able to forgive his former team-mate.
“What he [Ujah] has done has been reckless,” said Kilty, 33. “Everything has been a team effort to get to that position to be part of the British 4×100 strike four.
“Now he’s made that mistake I don’t think I’ll ever be able to forgive him because me, Zharnel and Nethaneel have lost a medal at the hands of his mistakes.
“CJ is ultimately going to be the one who is going to get banned himself — it is affecting his own career, but again we’ve worked so, so, so hard.
“We finally reached the pinnacle and won an Olympic medal, and then we lose it because one person has just been sloppy with what’s gone into their body. It’s heartbreaking.”
Britain’s men’s 4x100m squad finished behind Canada and the United States to take bronze at the World Championships in Eugene in July.