An article for controlled and substantially uniform release of a volatile active organic substance into the surrounding atmosphere includes a silicone elastomer matrix of desired shape in which are dispersed the volatile substance and an effective amount of an agent for compatibilizing the volatile substance and the silicone elastomer of the matrix. The compatibilizer is an organic solvent with a Hildebrandt solubility parameter from 8 (cal/cm.sup.3).sup.1/2 to 14 (cal/cm.sup.3).sup.1/2 and a vapor pressure from 0.0005 mm to 0.8 mm of mercury (0.06 Pa to 105 Pa) at 20.degree. C.