Mercury as a Control for Stored Grain Pests

Abstract

The Indian custom of placing metallic mercury with the grain in the storage container to prevent infestation by insects has been investigated. It is found to have a sound scientific basis as the presence of mercury prevents the reproduction of certain of these pests.Experiments showed that the vapour of mercury was fully effective in preventing reproduction of the grain weevil (Calandra granaria), the saw-toothed grain beetle (Oryzaephilus surinamensis), the lesser grain borer (Rhizopertha dominica), and the Angoumois grain moth (Sitotroga cerealella).Zinc and tin amalgams and calomel were less effective than metallic mercury.The efficiency of a given weight of mercury is increased by subdivision, a process which increases its total surface area.