[Interaction between benzene and toluene in long term inhalation exposure in rats (author's transl)].

Industrial chemicals are seldom used as pure substances; hazards resulting from exposure to mixtures have, however not been solved. Our study deals with chronic inhalation toxicity of a mixture of benzene and toluene; few studies have been completed on this subject. Our results show: - leucopenia with benzene alone, at a concentration of 50 p.p.m., that is not detectable in the presence of toluene; - metabolic variations consisting in: a decrease in the phenol urinary rate versus time with benzene alone; a sharp decrease of this rate from the third month of exposure on, in presence of toluene.