The storage of flour in jute bags treated with insecticides

Experiments are described in which flour stored in jute bags, the fabric of which had been impregnated with insecticides, was exposed to infestation by the species Ephestia kühniella, Ptinus tectus and Tribolium confusum. The use of 1% (w/w) of DDT in the fabric provided good protection against the first two named, and fair, but by no means absolute, protection against T. confusum. Transfer of insecticide to the flour occurred to an extent sufficient to be classed as contamination.