NEW YORK: Twenty-three Chinese swimmers tested positive for a banned drug before the Tokyo Olympics in 2021 the World Anti-Doping Agency confirmed on Saturday (Apr 20), defending the decision to let them compete based on China's findings they had ingested it unknowingly.

The New York Times and German broadcaster ARD reported on Saturday that the athletes included nearly half of the swimming team that China sent to Japan, with several going on to win medals, including gold.

Many are expected to be in contention again at the Paris Olympics this summer.

The Times reported that they tested positive for a prescription heart drug, trimetazidine (TMZ) - which can enhance performance - at a domestic meet in late 2020 and the first days of 2021.

But it was determined by Chinese anti-doping authorities that they ingested the substance unwittingly from tainted food and no action against them was warranted.

The newspaper cited a review of confidential documents and emails, including a report compiled by the Chinese anti-doping agency and submitted to its global counterpart WADA.

"NO FAULT OR NEGLIGENCE"

It said WADA and swimming's governing body World Aquatics, which at the time was known as FINA, decided not to act due to "a lack of any credible evidence" to challenge China's version of events.

WADA, in a statement on Saturday decrying "some misleading and potentially defamatory media coverage this week", said that it had "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."

WADA's senior director of science and medicine Olivier Rabin added: "Ultimately, we concluded that there was no concrete basis to challenge the asserted contamination."

World Aquatics confirmed to the Times the cases had been reviewed by a doping control board and were subjected to independent expert scrutiny.

But the United States Anti-Doping Agency said the swimmers should have been suspended and publicly identified, calling WADA's lack of action "a devastating stab in the back of clean athletes".

The organisation's chief executive Travis T Tygart claimed he had provided WADA with allegations of doping in Chinese swimming multiple...