Influence on blood of plasticized polyvinyl chloride: significance of the plasticizer.

An investigation has been made of the significance of the level of the plasticizer di-(2-ethylhexyl)phthalate at the surface of plasticized polyvinyl chloride for interactions with blood components. Plasticized polyvinyl chloride before and after treatment with methanol to reduce the plasticizer surface level was assessed in terms of fibrinogen and albumin adsorption with unplasticized polyvinyl chloride acting as a control. As the plasticizer surface level decreased, fibrinogen adsorption decreased almost linearly while albumin adsorption increased initially before decreasing slightly. The investigation indicates that reduction in the amount of plasticizer at the surface improves the blood compatibility of plasticized polyvinyl chloride, and the influence on blood is due primarily to the plasticizer rather than the polyvinyl chloride itself.