Pyrethrins are contact poisons with extremely short residual activity. Exposure to sunlight, air and moisture will degrade them within hours. Pyrethrins are generally mixed with a synergist and rotenone to provide better action against a wider variety of pests. Rotenone Rotenone is an alkaloid toxin extracted from the roots of two tropical legumes, Lonchocarpus from South America and Derris from Asia. Most of the current rotenone comes from Peru where it is often referred to as cube root.
Rotenone is extracted with acetone or ether and the concentrate is used to make products.
Some products simply use the powdered root. Rotenone disrupts cellular respiration and death is relatively slow compared to most nerve toxins. Rotenone is extremely toxic to fish and is used as a fish poison by South American Indian or in water management programs. It is also synergized by PBO or MGK 264. Most ingested rotenone is detoxified efficiently via liver enzymes.