The US Anti-Doping Agency handles drug testing for all fighters in the UFC. The Olympics, with all the world’s resources available, is having a difficult time clearly identifying whether someone is male or female. Thus it is no surprise that identifying if someone is taking performance enhancing drugs is more complex and nuanced than it appears.

UFC welterweight Augusto Montano tested positive for clenbuterol in an out-of-competition drug test on May 19. Further complicating matters, Montano tested positive for testosterone metabolites in a drug test administered after he lost to Cathal Pendred on June 13, 2015 at UFC 188, and was given a one-year suspension.

However, USADA investigated, and the Mexico City, Mexico based fighter will receive no sanction for the failure.

Via USADA.org

USADA announced today that UFC athlete Augusto Montano, of Mexico City, Mexico, has tested positive for a prohibited substance, which was determined to have been ingested by him without fault or negligence.

Montano, 31, tested positive for trace amounts of clenbuterol as the result of an out-of-competition urine sample he provided on May 19, 2016. Clenbuterol is an Anabolic Agent prohibited at all times under the UFC Anti-Doping Policy, which has adopted the World Anti-Doping Agency (WADA) Prohibited List. Consistent with numerous prior reported cases globally, the issue of illicit administration of clenbuterol to animals destined for food production can result in, under specific conditions, a positive sample from an athlete. WADA has issued specific warnings about this problem in China and Mexico. To USADA’s knowledge, positive tests resulting from meat contamination issues are rare outside of those two countries. Moreover, due to strict regulatory and meat certification practices, USADA is not aware of any instances in which an athlete’s sample tested positive for clenbuterol after consumption of meat produced in the U.S.

USADA was informed of Montano’s positive test result in June 2016, and immediately initiated an investigation to determine the circumstances that led to the positive test. As part of the investigation, USADA interviewed Montano on multiple occasions and reviewed all available relevant evidence, including Montano’s whereabouts, dietary habits, and the laboratory reports demonstrating very low parts per billion concentrations of the prohibited substance in the athlete’s urine sample. Based on this information, USADA concluded that the presence of clenbuterol in the athlete’s sample very likely resulted from clenbuterol contaminated meat consumed in Mexico. USADA’s investigation also took into consideration a negative result for a sample collected after Montano’s positive test. As a result, Montano will not face a period of ineligibility for his positive test.

While the risk of consuming clenbuterol-tainted meat and testing positive for an athlete is extremely small, consistent with past athlete advisories, USADA reminds athletes to use the utmost care if eating meat in known high risk countries, including Mexico and China. In line with WADA recommendations, USADA will continue to assess the presence of clenbuterol in an athlete’s sample on a case by case basis, taking into account all the evidence supporting the likelihood of such contamination.

Montano will fight Belal Muhammad at UFC Fight Night 94: Poirier vs. Johnson on September 17, 2016 at State Farm Arena in Hidalgo, Texas, as scheduled.

Montano is not the only UFC fighter to recently test for clenbuterol.

Bantamweight Ning Guangyou of China tested positive for clenbuterol, and, like Montano will not be sanctioned.

Welterweight Li Jingliang, also from China, tested positive for clenbuterol. The investigation has not concluded, but in a positive sign, Jingliang has not been provisionally suspended by USADA.

Adding a further layer of complexity to Jingliang case, as the test failure was in proximity to a fight with Anton Zafir on July 8 in Las Vegas, it also fell under the jurisdiction of the Nevada Athletic Commission. The NAC has temporarily suspended Jingliang, and will require the fighter to go before a board to further determine what happened. Even if USADA declines the sanction the fighter, the NAC could, in theory, suspend him.

California-based US Bantamweight Francisco Rivera also tested positive for clenbuterol, just this month, and has been provisionally suspended, pending a full investigation. The fighter reports that he was in Mexico on vacation recently, and cited contaminated meat there as the likely origin of the failure.