The effect of various radiations from radium on Mercurochrome was studied by irradiating both the solutions and the solid crystals of the drug. The action of alpha and beta radiations was studied by crushing glass globules containing radium emanation in doses of 4 to 10 millicuries directly under solution of 2% Mercurochrome in water and immediately stoppering tightly the 10 cc. vials of the solution. The effect of gamma rays was studied by placing vials of Mercurochrome solution in juxtaposition to large quantities of radium. The irradiations of solid Mercurochrome crystals was performed in the same way. The pharmacological and bacteriological properties of the solid crystals after irradiation were studied by making a 2% solution of the same. Bacteriological studies were made in the following manner: Cultures of B. typhosus were used; the method of studying germicidal action was the so-called Hygenic Laboratory method. The temperature of medication was 20°; the proportion of culture and disinfectant used for making dilutions were 0.1 cc. in 5 cc. Subculture medium was also that of the Hygenic Laboratory method. Quantity used in each tube was 10 cc. Temperature of the incubator was 37°. Various dilutions of the drugs were employed. Time of exposure of the culture to the action of the disinfectant was in one series of experiments 5 minutes and in a second, 15 minutes. Control experiments with unradiated Mercurochrome solutions from exactly the same stock were made in exactly the same way. It was found that when solutions treated with the alpha and beta radiations were examined within 24 to 48 hours, there was a slightly increased bactericidal activity shown after 5 minutes exposure to the disinfectant. This increased bactericidal property of the solution, however, disappears after a few days.
