A Radical Point of View: Journey of a Free Radical in a Struggle Against Enzymes and the Body

Although you aren't a free radical, you are still H2O2 (with some O2, if you came from superoxide), and need to be further reduced. That's where catalase comes in! Found in almost all organisms that are exposed to oxygen, this enzyme breaks H2O2 into water and more O2. If you happened to pass through the liver, you would find an excess of catalase there. Which makes sense, as this organ is responsible for cleaning blood within the human body.