The World Anti-Doping Agency (WADA) is allowing athletes to a trace amount of the performance-enhancing drug meldonium after banning the substance it in January, Russian state news agency TASS reported Wednesday.
The WADA will allow a concentration of up to one microgram of meldonium per millilitre in test samples collected before March 1, a trace amount that could still be present if the athlete stopped taking the drug before it was banned on January 1, the report said.
On Friday, Russia's sport minister Vitaly Mutko threatened to take legal action against the WADA if it did not provide a grace period for Russian athletes who used meldonium before it was banned.
The drug was developed by the Soviet Union to aid blood circulation, and some 140 athletes from several countries, led by Russian tennis star Maria Sharapova, have been suspended after testing positive for it.
Mutko told reporters that traces of meldonium can remain in a user's body for up to a year. WADA informed athletes last autumn that the substance would be added to the prohibited list.
