PBO acts as an insecticide synergist by inhibiting the natural defense mechanisms of the insect, the most important of which is the mixed-function oxidase system, (MFOs) also known as the cytochrome P-450 system. The MFO system is the primary route of detoxification in insects, and causes the oxidative breakdown of insecticides such as pyrethrins and the synthetic pyrethroids[7] - thus when PBO is added, higher insecticide levels remain in the insect to exercise their lethal effect.[8] An important consequence of this property is that, by enhancing the activity of a given insecticide, less may be used to achieve the same result.[3]