What is synergism?

It is a term used by toxicologists to describe the phenomenon in which a combination of chemicals has a tonxic effect greater than the sum of its parts. In the manufacture of pesticides, toxic chemicals are deliberately combined to produced synergistic effect using an additive known as ‘potentiator’ or ‘synergist’ to enhance the action of the basic active ingredient. Piperonyl butoxide is added to the insecticide rotenone to promote synergistic effects. Pollutants copper and cadmium on fish show synergistic interactions.