Abstract: The invention serves to prevent or delay the formation of undesired phosphine levels in packages in which phosphine releasing compositions (in particular hydrolysable metal phosphides) are packaged and stored and in environments to be fumigated during the period of introduction of phosphine-releasing compositions. This is brought about by maintaining in the immediate vicinity of the composition a zeolite having a pore width from 0.3 nm upwards, preferably 0.4 to 1.5 nm and an adsorbtive affinity for moisture or phosphine or preferably both. The zeolite is employed either as a separate item in the package or as part of the composition, admixed or as a coating. In a mass ratio of metal phosphide to zeolite are from 1:0.05 to 1:2. The adsorption of phosphine to the zeolite is reversible and on exposure to an environment to be subjected to pest control, the zeolite will release the adsorbed phosphine by replacement by atmospheric humidity.

Abstract: A pest control product is provided from a metal phosphide particle coated with a water soluble coating that has been rendered water repellent. The coating also contains a material which will chemically or physically disintegrate to cause apertures in the coating to provide access for water to the phosphide particles.

Abstract: The present invention relates to a pesticide comprising a molded body made of a water-insoluble organic solid substance in which at least one finely divided metal phosphide is embedded, the molded body being coated on at least one side with a fibrous substance which is permeable to water vapor and the fibers of which at least partially extend as far as the embedded phosphide particles, and to a process for producing such a pesticide.

Abstract: Storage stable, quickly acting tablets for combatting vertebrates living preponderantly in underground structures are provided consisting of a mixture of commercial magnesium phosphide and at least one molding aid placed in a cavity depending on the size of the tablet in a water vapor impermeable, tear and break resistant film covered with a water vapor impermeable, non-tear resistant, non-break resistant film, the two films being sealed together tightly against water vapor and air at their edges.

Abstract: The present invention relates to a phosphine-developing pesticide which comprises at least one phosphide selected from the group consisting of magnesium phosphide and aluminium phosphide, a thermally decomposable material and polyethylene oxide having a molecular weight of between 4000 and 12000 and to a process for producing the same.