A relatively new diatomaceous earth of marine origin, Insecto, has been extensively assessed in the USA. Dosages up to 0.15% (w/w) induced complete mortality of adult insects exposed to small quantities of treated wheat or barley in the
laboratory. Secondary pest feeders, such as 0. surinamensis, 0. mercator, Cryptolestes ferrugineus (Stephens) and C. pusillus (Schonherr) were particularly sensitive. Similar treatments to maize were not as effective, particularly against internal feeders including S. oryzae and R. dominica. These authors also found Insect0 to be effective against larval stages of T. castaneum, 0. surinamensis and Plodia interpunctella, reducing the percentage of adult emergence.