COMPOSICAO E PROCESSO PARA O DESPRENDIMENTO CONTROLADO A LONGO TERMO,DE UM PESTICIDA NAOPERSISTENTE ORGANOESTANHO,DE UM DISTRIBUIDOR TERMOPLASTICO MONOLITICO,INERTE

. A method and composition for destroying pest insects in their aquatic stage and other pest-life forms over a sustained period of time, by the gradual and continuous release of an organotin substance from an inert thermoplastic medium. The composition comprises an organotin of extremely low water solubility bound in an ethylene vinyl acetate copolymer, in which said organotin is insoluble and in which said organotin is uniformly dispersed with an inert coleachant of moderate water solubility. When this formulation is brought into contact with water, the coleachant gradually solvates into the water creating and enhancing the development of porosity within the thermoplastic phase. Said organotin agent, interspersed within the thermoplastic matrix, contacts the entering water and egresses as molecular aggregates being washed through the pore system and into the external watery medium. Such aggregates being toxic to mosquito larva, other insects and various other pesteferous life forms, upon continuous exposure, leads to a condition of terminal chronic intoxication.