THE PRESENT INVENTION PROVIDES AN INSECT OR ARTHROPOD PESTICIDAL COMPOSITION. THE COMPOSITION INCLUDES ACTIVE INGREDIENTS HAVING A MIXTURE OF FATTY ACIDS, EACH OF THE FATTY ACIDS HAVING A STRAIGHT CARBON CHAIN FROM 6 TO 12 CARBON ATOMS LONG. THE FATTY ACID MIXTURE INCLUDES A FIRST FATTY ACID MOLECULE HAVING A STRAIGHT CARBON CHAIN FROM 6 TO 8 CARBON ATOMS LONG, AND A CARBOXYLIC ACID GROUP. THE FATTY ACID MIXTURE ALSO INCLUDES A SECOND FATTY ACID MOLECULE HAVING A STRAIGHT CARBON CHAIN FROM 8 TO 12 CARBON ATOMS LONG, AND A CARBOXYLIC ACID GROUP. THE COMPOSITION ALSO INCLUDES A CARRIER THAT PROMOTES ADHERENCE OR ABSORPTION OR TRANSPORT ACROSS THE SURFACE OF INSECTS OR ARTHROPODS TO EFFECT THEIR INCAPACITATION OR DEATH.