The invention is a composition that can prevent formation in, or scavenge undesirable organic materials from, a polymer matrix. The composition contains cyclodextrin and particles of activated carbon. The composition can scavenge thermal decomposition products that can be produced during melt processing of a polymer, contaminants inherent in a polymer, or other types of impurities from a polymer matrix that otherwise may elute into the air, a water supply, or an ingestible material such as a food, a drug, or a beverage. Other aspects of the invention are blends of the composition with polymeric materials, methods of making blends, articles containing the composition, and methods of making articles containing the composition.