a dynamic challenge, for established ones are continually being dis­ placed by newly developed ones more acceptable to food tech­ nologists, pharmacologists, toxicologists, and changing pest-control requirements in progressive food- producing economies. These matters are of genuine concern to increasing numbers of governmental agencies and legislative bodies around the world, for some of these chemicals have resulted in a few mishaps from improper use. Adequate safety-in-use evaluations of any of these chemieals per­ sisting into our foodstuffs are not simple matters, and they incorporate the considered judgments of many individuals highly trained in a variety of complex biological, chemical, food technologieal, medical, pharmacological, and toxicologial disciplines.