Reglon (20 per cent dikwad dibromide) is an extensively used herbioide and desiccant. During acute and chronic inhalatory experiments on white rats, using 4--hour exposure to water aerosols, determination is made of the acute LC50 -- 83 mg/m3, of the acute threshold concentration - 9.9 mg/m3 acute substance, as well as of the chronic threshold concentration - 0.32 mg/m3. In all instances the clinical picture of intoxication is characterized by pulmonary lesion, and partial involvement of liver and kidneys. The computed zones of acute and chronic inhalatory toxicity warrant the assumption that no sequelae dueto herbicide cumulation in the organism should be expected. At safety coefficient 3, the authors propose 0.1 mg/m3 dikwad dibromide as a temporary limit of the maximum allowable concentration of reglon in the working environment air.