PVC-plasticizer DEHP - aspects of metabolism and toxicity.

Di-(2-ethylhexyl)phthalate (DEHP) is the most important compound among a group Of phthalic acid alkyl esters used as plasticizers for PVC-products. Since DEI-IP is not covalently bound to the polymer, it can be released from the plastic matrix. Its migration from PVC-based tubings, storage bags and dialysis bags contributes substantially to the increased exposure of patients to plasticizers. After oral, intravenous or inhalational uptake, DEHP is hydrolyzed to mono-(2-ethylhexyl)phthalate (MEHP) and 2-ethylhexanol (2-EH). These cleavage products are further metabolized to a variety of oxidation and conjugation products which are predominantly eliminated via the kidneys. The acute toxicity of DEHP is low. Following chronic exposure of laboratory animals to higher doses of DEHP, hepatotoxic, nephrotoxic, carcinogenic and reproductive toxic effects have been observed. The relevance of these observations to humans is currently unknown. Therefore, further studies on the potentially harmful effects of DEHP are required, particularly in view of the increasing exposure to DEHP in the coming years.