Cyclodextrin inclusion: catalytic effects on the degradation of organophosphorus pesticides in neutral aqueous solution.

alpha-, beta and gamma-Cyclodextrins were found to have promotive inclusion-catalytic effects on the degradation of organophosphorus pesticides solubilized in neutral aqueous media. Pesticide degradations were especially accelerated in such systems as alpha-cyclodextrin plus diazinon and beta-cyclodextrin plus chloropyrifos. The above findings are in contrast with the inhibitive catalytic effects of cyclodextrins on pesticide degradations in alkaline media. Cyclodextrin catalytic effects found here were considerably affected by differences in the substitutional and hetero-cyclic properties of the aromatic rings of pesticides and also by the sizes of cyclodextrin cavities.