Catalase is an enzyme that is found in living organisms that catalyzes the decomposition of hydrogen peroixde to oxygen and water. Hydrogen peroxide is highly toxic within the cell and is produced as a by-product of metabolism. Catalase ensures the cells are not damaged by this chemical and produces oxygen and water, which are harmless within the body.
Catalase is found in an animal cell's peroxisome, especially liver and kidney cells. It catalyses uses the hydrogen peroxide generated by the cell to oxidise other chemicals such as phenol and alcohol. It is an important part of the detoxification process within the body 
- ↑ Alberts et al., Molecular Biology Of the cell, 5th edition, 2008, Garland Science, New York, pg 721.