An appraisal of fenitrothion as a promising grain-protectant.

In tests in India to evaluate the comparative effectiveness of malathion, diazinon and fenitrothion against the stored product pests Tribolium castaneum (Hbst.), Sitophilus oryzae (L.) and Callosobruchus (Bruchus) chinensis (L.) adult beetles were confined in petri dishes that had previously been sprayed and allowed to dry. The LD50's obtained are shown in a table. Both diazinon and fenitrothion were considerably more toxic to all three species than malathion, and diazinon was more toxic than fenitrothion to S. oryzae and C. chinensis. A review of the literature on the persistence of fenitrothion on various substrates and the costs of treatment indicate that this compound is the most promising alternative to malathion for the protection of stored products, particularly grain. Diazinon cannot be recommended in view of its relatively high mammalian toxicity.