Wastewater is a chemical cocktail. In livestock farming, antibiotics and heavy metals get used side by side. Oxytetracycline, a broad-spectrum antibiotic, goes into animal feed as a growth promoter. Zinc, an essential trace element, gets supplemented at high doses, often as zinc oxide. Both end up in manure. Both end up in the environment. And when they meet, they react. The question is what happens when these two pollutants hit a wastewater treatment system that uses anaerobic ammonium oxidation, or anammox. What Is Anammox Anammox is a bacterial process that converts ammonia and nitrite directly into nitrogen gas. It works without oxygen and without organic carbon. Compared to traditional nitrification-denitrification,…