[Experimental substantiation of the maximum permissible concentration (MAC) of polyvinyl chloride resin]

The acute and chronic oral, dermal and inhalatory toxicity of PVH resin is studied in white rats. It is established that in acute treatment, irrespective of the route of PVC resin penetration into the organism, its effect proves weakly toxic. During chronic oral and inhalatory experiments, a slight affection of peripheral blood elements only is noted. In the lungs of the animals inhalating 2 and 6 mg/m3 concentrations for a duration of four months, no changes are detected which might be interpreted as being PVH specific. Cumulative effect, and skin stimulating and sensibilizing action of the polymer are neither established. Against the background of the obtained results, a provisional normal MAC value is proposed, namely 2 mg/m3 of PVH dust in the air of the working environment.