The Problem With DEHP
In addition to the characteristics that make it useful for medical devices, DEHP is also highly lipophilic (fat soluble). When used in PVC plastic, DEHP is loosely chemically bonded to the plastic and readily leaches into blood or other lipid-containing solutions in contact with the plastic. The rate of DEHP leaching depends on many factors. The type of solution in contact with the plastic, temperatures during storage and at the time of use, storage time, and percent DEHP in the plastic product all play a part (Marcel, 1973).
This leaching of DEHP into humans via the solution with which it is in contact increases the risk of certain adverse health outcomes. Animal studies show that exposure to DEHP can damage the liver, kidneys, lungs, and reproductive system, particularly the developing testes of prenatal and neonatal males. The FDA and National Toxicology Program's Center for Evaluation of Risks to Human Reproduction conclude that these animal studies are relevant to people.
As stated in the 2002 Aggregate Exposures to Phthalates in Humans report, "[d]eveloping organisms are uniquely vulnerable to phthalate exposures, and in particular, the developing male reproductive tract appears to be the most sensitive organ system. Abnormal development of the testes, penis, and other components of the male reproductive tract occurs at levels of exposure that are hundreds or thousands of times lower than those necessary to cause damage in adults (DiGangi, Schettler, Cobbing, & Rossi, 2002).
More recently, researchers at Harvard School of Public Health have found that babies in neonatal intensive care units have high exposure levels to this reproductive toxicant. For the peer-reviewed study, researchers measured the level of a DEHP metabolite in the urine of neonates treated in the NICUs, and were able to correlate the level of exposure to DEHP-containing products to the level of DEHP metabolite found in the babies' urine. Infants who received intensive treatments with PVC medical devices were exposed, on average, to levels of DEHP that were 25 times higher than levels measured in the general population by the U.S. Centers for Disease Control. As their medical treatments intensified, the sick infants were exposed to progressively higher exposures of DEHP (Green et al., 2005).
Pediatr Nurs. 2006;32(1):91-93. © 2006 Jannetti Publications, Inc.
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