Conference on phthalates. June 9-11, 1981 Washington, DC.

The use of plastics and plastic-containing products is a reality of modern life that has transformed both the home and work environments. In addition to the polymerized molecules that form the matrix of the plastic, however, other chemicals (adjuvants) are commonly incorporated into plastic products to impart specific use or performance characteristics such as combustion resistance, color enhancement or resiliency. O0tho esters of phthalic acid, or phthalate esters as they are generally referred to, have been used to impart flexibility to plastics and may comprise as much as 50% by weight of the final product. Such plasticizers are not polymerized into the plastic matrix and may, with time and use, migrate from the plastic and into the external environment (although the plastic products are obviously designed to retain the plasticizer and, thereby, remain flexible). Readers are referred to an earlier, comprehensive report for more information on the use of phthalate ester plasticizers (1). Di(2-ethylhexyl) phthalate (DEHP) is the most commonly used plasticizer for poly(vinyl chloride) products, including syringes, dialysis tubing and other medical devices. DEHP is also used as a dielectric fluid in transformers and as a hydraulic fluid in heavy machinery. An estimated 400 million pounds of DEHP is produced annually in the United States (2). Since all plastic products are ultimately disposed of in the environment, human exposure to DEHP and other components of plastics can occur via contact with water and soil (and air, in some instances), as well as through direct contact with plastic products.