PVC as a biomedical polymer--plasticizer and stabilizer toxicity.

During the last 40 years PVC has become the most widely studied and understood polymeric biomaterial. The success of PVC compounds is due to their ability to fulfill the complex needs of the medical device industry. The range of properties they possess, which includes flexibility and low toxicity, is achieved by their various formulations. Plasticizers are used to meet many of the requirements and because of their ability to be extracted into biofluids they present the greatest toxicological risk. In his discussion, the author looks at the ingredients of compound formulations and the influence of plasticizers on the toxicity. A detailed report is provided of studies carried out in connection with di(2-ethylhexyl)phthalate (DEHP), the most extensively used plasticizer, and the author questions the validity of using the results of animal tests for the assessment of risk to humans. A description of the commercial production of PVC polymers and a review of the various pharmocopoeia and national standards and requirements are also included.