An Olympic swimming champion who was one of 23 Chinese athletes who tested positive for a banned substance before the last Summer Olympics said on Saturday that they had been wrongly accused of doping and insisted that China would never allow any athlete to use performance-enhancing drugs.

The remarks by the swimmer, Zhang Yufei, were the first public comments by a member of the Chinese swimming team at the center of the doping scandal, which has brought anger, accusations and resentment to the Paris Olympics, the sport’s grandest stage.

“I don’t think any athlete, Chinese or non-Chinese, would want to destroy the work they built up every day over the years on doping,” Zhang said at the Olympic pool after a fast swim in a morning race on the opening day of the swimming competition. The Chinese government, she said, “also does not allow us to dope on purpose.”

Zhang offered her responses in an interview in Mandarin that was translated into English.

Zhang and her Chinese teammates tested positive for a banned substance at a domestic meet in early 2021, but they were allowed to continue competing, including at the Olympics later that year, after a Chinese investigation declared that the positive test was the result of accidental contamination. Zhang went on to win four medals in Tokyo — two gold and two silver — and helped break a world record with her freestyle relay teammates.

On Saturday, Zhang reiterated what the Chinese authorities and the World Anti-Doping Agency have claimed for months: that the positive tests for the banned substance, trimetazidine, a prescription heart medication, were the result of food contamination traced to a hotel kitchen. Chinese officials and WADA officials declined to punish the swimmers and kept the results secret, despite rules at the time that should have led to their public disclosure.