23 Chinese swimmers tested positive for banned substance before 2021 Olympics: WADA

The World Anti-Doping Agency confirmed that nearly two dozen Chinese swimmers tested positive for a banned substance months before the Tokyo Olympics in 2021, while defending its review of the positive tests, which China blamed on contamination.

WADA confirmed in a statement released on Saturday that 23 Chinese swimmers tested positive for trimetazidine, or TMZ, a performance-enhancing drug, in early 2021. The agency also pushed back against what it called "misleading and potentially defamatory media coverage," in response to media reports alleging that the agency had dismissed the positive results.

The New York Times and the Daily Telegraph both reported on the positive tests on Saturday. The Times reported that there was no public disclosure at the time of the positive tests and no suspensions for the swimmers, who it said made up nearly half of the team China sent to the Tokyo Games and in some cases won medals.

WADA said that the China Anti-Doping Agency (CHINADA) notified them in June 2021 of its decision to accept that the swimmers tested positive "after inadvertently being exposed to the substance through contamination." WADA said it then spent weeks reviewing CHINADA's decision and the contamination theory.

"As part of its review, WADA collected additional, unpublished scientific information on TMZ and consulted with independent scientific experts to test the contamination theory and also whether low doses of TMZ could have benefited the athletes during a swimming competition event," WADA said.

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WADA said its investigators were unable to go to China due to COVID-19 restrictions and that they "ultimately concluded that it was not in a position to disprove the possibility that contamination was the source of TMZ and it was compatible with the analytical data in the file."

"WADA also concluded that, given the specific circumstances of the asserted contamination, the athletes would be held to have no fault or negligence," the agency said. "As such, and based on the advice of external counsel, WADA considered that an appeal was not warranted."

Olivier Rabin, the senior director of science and medicine for WADA, said in a statement that the contamination scenario was supported by the "consistently low concentrations as well as no doping pattern."

WADA Intelligence and Investigations director Gunter Younger said the threshold to open an investigation was not met "based on the available information and a lack of any credible evidence."

"At every stage, WADA I&I followed all due process and diligently investigated every lead and line of enquiry in this matter," Younger said in a statement.

WADA informed the International Testing Agency, a Switzerland-based anti-doping group that provides independent oversight of international sports competition, according to Rabin.

International Testing Agency's review of the case is ongoing, according to The Times.

In a statement to The Times, CHINADA said that it found that its athletes did not violate anti-doping laws and could not release details on the case without their consent.

WADA's statement did not identify any of the swimmers involved.

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United States Anti-Doping Agency CEO Travis Tygart said it was "crushing" to see that the Chinese swimmers tested positive for TMZ leading up to the 2021 Olympic Games.

"It's even more devastating to learn the World Anti-Doping Agency and the Chinese Anti-Doping Agency secretly, until now, swept these positives under the carpet by failing to fairly and evenly follow the global rules that apply to everyone else in the world," Tygart said in a statement on Saturday. "Our hearts ache for the athletes from the countries who were impacted by this potential cover-up and who may have lost podium moments, financial opportunities, and memories with family that can never be replaced."

Younger denied there was any cover-up in his statement, saying, "The data held by us clearly showed that there had been no attempt to hide the positive tests as they had been reported in the usual way by the Chinese authorities."

TMZ is a medication that increases blood flow to the heart and is used to treat angina. It has been banned by WADA since 2014.

Russian skater Kamila Valieva tested positive for the drug before the 2022 Beijing Winter Olympic Games. The then-15-year-old was allowed to compete but later disqualified by the Court of Arbitration for Sport, stripping Russia of its team event gold medal.

Valieva claimed that her positive drug test was a result of a mix-up with her grandfather's heart medication, Olympic officials said.

23 Chinese swimmers tested positive for banned substance before 2021 Olympics: WADA originally appeared on abcnews.go.com