Toxicity of Some Nitro-Phenols as Stomach Poisons for Several Species of Insects

Abstract

An examination has been made by means of the leaf sandwich method of the toxicity of several nitrophenol compounds to last-instar corn ear-worms, army worms and cabbage worms. 2-4 dinitro-6-cyclohexyl phenol and the Ca, Mg, Pb and Cu salts are several times as toxic as acid lead arsenate to the corn ear-worm. Ca 2-4 dinitro-6-cyclohexyl phenate is the most toxic substance tested, it being 4.4 times as toxic as Pb arsenate to the corn ear-worm and 17 times as toxic to the army worm. Furthermore, the speed of toxic action of the dinitro compounds is several times as great as that of lead arsenate. With the red legged grasshopper the Ca salt of 2-4 dinitro-6-cyclo-hexyl phenol is of low toxicity, but the free phenol is 2.5 times as toxic as arsenious oxide, and its action is faster. The chemicals related structurally to 2-4 dinitro-6-cyclohexyl phenol have little toxicity as stomach poisons. The arrangement of substituents on the benzene ring is very important.