ACUTE ORAL TOXICITY OF MONURON IN ALBINO RATS FED FROM WEANING ON DIFFERENT DIETS

Male albino rats were fed from weaning on purified diets containing 0.0 (I), 3.5 (II), 9.0 (III), and 26% (IV) protein as casein. At the end of 28 days of feeding, the acute oral LD50 ± S.E. of monuron was found to be 0.25 ± 0.05 gram per kg. body weight in group I, 0.95 ± 0.24 in II, 1.58 ± 0.47 in III, 2.88 ± 0.31 in IV, and 1.48 ± 0.21 in control rats fed a standard laboratory chow. The clinical syndrome of toxicity at the range of the LD50 was essentially the same in rats of all dietary groups. At autopsy there was found a local irritant gastroenteritis accompanied by degenerative changes in the liver and kidneys, a stress reaction and loss of weight, and insignificant alterations in water content of most body organs. © 1969, American Chemical Society. All rights reserved.