The UFC, in coordination with the United States Anti-Doping Agency, announced Monday changes to its anti-doping policy.

The fighting promotion will adopt the "UFC Prohibited List," which institutes thresholds for substances that are proven to be regularly found as contaminants at levels that don't give fighters an athletic advantage.

Athletes won't be sanctioned if they test positive for one of the listed substances at a level under the concentration level. Instead, the sample will be treated as an atypical finding rather than an adverse analytical one.

Fighters will be directed to use only supplements certified by NSF Certified for Sport, the Cologne List, Informed Sport Trusted by Sport, Human and Supplement Testing Australia, and/or Banned Substance Control Group.

Athletes will also not be sanctioned if they test positive for a certified supplement or an environmental contamination, such as from food, water, or prescription medication.

The UFC has partnered with Thorne supplements to provide fighters with certified products through the UFC Performance Institute.

"Putting forth a fair anti-doping program with due process protection is integral to having a strong and comprehensive program," UFC senior vice president of athlete health and performance Jeff Novitzky said in a release.

He added: "A combination of the pervasiveness of low-level contaminants in our environment and the increased levels of testing sensitivity of anti-doping laboratories has created an explicit need for decision concentration levels to ensure that the program is penalizing intentional cheaters and not those athletes who have been faithfully adhering to the anti-doping policy."