| abstract |
Particulate pesticidal compositions having self-destructing properties are prepared by coating a particulate metal core with a solid acid or a metal salt which hydrolyzes to produce an acidic environment. The acid layer is then coated with a second layer of an isolating material, such as poly vinyl alcohol, which degrades after exposure to field conditions. A normally persistant pesticide, such as DDT, is adhesively coated on the exterior of the isolating layer. Upon exposure to field conditions, the isolating layer degrades allowing moisture to react with the solid acid or hydrolyzable salt thus allowing the metal core, which may be metallic zinc or a metallic couple such as zinc-copper, to react with the pesticide to produce degradation products having greatly reduced physiological activity than that displayed by the pesticide. |