[Effect of small amounts of 2,4-dichlorophenoxyacetic acid derivatives on thiamine and riboflavin metabolism in the animal body].

Administration of the herbicide 2,4-DN (amine salt of 2,4-dichlorphenoxyacetic acid) to weanling rats in a dose of 1/20.000 and 1/2000 of the LD50 for 3 months brought about a 40-50% reduction of thiamine content in the organs and tissues of experimental animals as compared with control. The herbicide was introduced into a balanced formula diet. In the liver of rats given 2,4-DA, there was a 2-fold decrease in the content of flavine adeninedinucleotide, whereas the content of flavine mononucleotide showed a 2-fold rise. Besides, the rats given a lesser herbicide dose manifested a reduced excretion of riboflavine with urine, and an inhibition of liver succinate dehydrogenase. The same animals demonstrated an increase in the relative mass of the adrenals with a concurrent diminution in them of ascorbic acid content.