Two Chinese athletes, one of whom was named to the Olympic team in Paris, tested positive in 2022 for a banned steroid. China blamed contaminated food, as it had after previous positive tests.

Two elite Chinese swimmers, including one named to her country’s team in the Paris Olympics, tested positive in 2022 for a banned drug but were secretly cleared of doping late last year by Chinese authorities, according to two people with direct knowledge of the matter.

After a lengthy investigation into the previously undisclosed incident, the Chinese authorities were unable to determine exactly how the swimmers ingested the drug, a powerful anabolic steroid, but concluded that they had most likely done so unwittingly when they ate hamburgers at a restaurant in Beijing.

The Chinese emphasized in their explanation to global antidoping regulators that only trace amounts of the steroid had been detected and said that those levels were consistent with contamination, not doping.

The decision to clear the swimmers was at least the third time in recent years that China has blamed contaminated food for positive tests by top swimmers, an explanation that has drawn skepticism from many antidoping experts. Critics see the incident as the latest in a pattern of China’s looking the other way when confronted with positive tests in its swimming program, and as a failure by global antidoping agencies to ensure a level playing field for elite athletes.