EUGENE, United States, June 20, 2024 (BSS/AFP) - US sprint star Erriyon Knighton tested positive for a banned steroid earlier this year but has been cleared to take part in upcoming US Olympic track and field trials after an arbitrator ruled the substance was ingested through contaminated meat, the United State Anti-Doping Agency (USADA) said on Wednesday.

Knighton, silver medallist in the 200m at the 2023 World Championships and a bronze medallist in the same event at the 2022 worlds, tested positive for trenbolone during an out of competition test in March.

However after hearings on June 14 and 16 involving Knighton, USADA and other witnesses, an independent arbitrator ruled the case should be treated as a "no fault" violation, meaning Knighton will avoid a suspension.

"We did what the rules require us to do in all positive cases," USADA chief executive Travis Tygart said in a statment.

"We can take comfort that justice was served and transparency as required by the rules was achieved."

The USADA statement said the arbitrator overseeing the case found that Knighton's positive sample was "more likely than not caused by consuming meat contaminated with trenbolone."

The agency described trenbolone as "a known livestock growth promoter that is used legally in beef cattle produced in and exported to the United States."

Because Knighton's test was taken outside of competition, there are no results to disqualify.

The American sprinter was provisionally suspended on April 12, 2024, a suspension which has been lifted effective immediately.

Knighton is free to run at the US Olympic trials in Eugene, Oregon, which get under way on Friday.