A federal judge on Thursday ordered regulators to start proceedings to withdraw approval for the use of common antibiotics in animal feed, citing concerns that overuse is endangering human health by creating antibiotic-resistant “superbugs”.

U.S. Magistrate Judge Theodore Katz ordered the U.S. Food and Drug Administration to begin proceedings unless makers of the drugs can produce evidence that their use is safe.

If they can’t, then the FDA must withdraw approval for non-therapeutic use of those drugs, the judge ruled.