The joint inhibitory effects of phenol, copper (II), oxytetracycline (OTC) and sulfide on Anammox activity.

A batch test was employed to analyze the joint toxicity of copper (II) and oxytetracycline (OTC), OTC and sulfide, phenol and sulfide (S(2-)), phenol and copper (II), and OTC, copper (II) and substrate on an Anammox mixed culture. The joint toxicity of OTC and copper (II) on the Anammox mixed culture was antagonistic, whereas the interaction between OTC and S(2-) and between phenol and S(2-) was generally synergistic. The joint toxicity of phenol and copper (II) was dependent on the level of phenol: the joint toxicity was antagonistic at a high phenol level of 300 mg L(-1), whereas the joint toxicity was synergistic at a low phenol level of 75 mg L(-1). The joint toxic effect of OTC, copper (II) and NO(2)(-)-N on the Anammox activity can be ranked in the following order: NO(2)(-)-N>copper (II)>OTC.