The chemical compound DEHP, Di(2-ethylhexyl) phthalate, is contained in many of
the common plastic products found in health care settings. It is in a category of
toxic chemicals known as pthalates, which are commonly added to polyvinyl chloride
(PVC) plastic to make the plastic product flexible and strong. It allows the otherwise
stiff PVC to be molded into a variety of products such as IV tubing, IV bags, and
feeding tubes. By weight, DEHP comprise 20- 40% of the PVC products on average.
There is new evidence regarding the human toxicity associated with exposure to DEHP
that should help to inform our product selection in the health care setting.
"DEHP does not bind with plastic, so it can leak out of PVC medical products
during medical procedures, or when PVC objects such as toys are chewed. Everyone
is exposed to DEHP through off-gassing from vinyl products in the home and workplace,
as well as from industrial emissions. However, some infants and especially pre-term
neonates are receiving, in some cases, megadoses of DEHP. Neonatal nurses should
know what they can do to protect their tiny patients from the potentially harmful
effect of DEHP. The multiple and relatively high exposures that may occur in neonatal
intensive care units (NICUs) are significant. Many of these babies are exposed during
blood and other intravenous infusions, respiratory therapy, enteral feedings and
extra corporeal membrane oxygenation (ECMO)" (quote from Ann Melamed in The
American Nurse, December 2000, online at
www.nursingworld.org/tan/novdec00/pollutio.htm).
The National Toxicology Program's Expert Panel who reviewed DEHP studies only
looked at reproductive and developmental effects. Based on animal studies, there
are concerns that there may also be effects on the liver, kidneys, and lungs, as
well as effects on heart rate and blood pressure.
So how does the chemical DEHP create a risk to humans when it is in PVC medical
devices? When it is in PVC, it is not actually bound chemically. It can therefore
escape the PVC product under certain conditions such as when the product is heated,
or when the medical device contacts fluids—such as the fluids that would be in an
IV or blood bag. DEHP migrates into a variety of fluids including blood, plasma,
and total parenteral and enteral nutrition solutions. During medical interventions
that require long-term IV interaction such as hemodialysis or ECMO, DEHP exposure
is significantly enhanced. Pediatric exposures are of the greatest concern. Sick
newborns and infants face the greatest risk of exposure from medical interventions
and may also be the most vulnerable to the toxic effects of DEHP because of their
stage in human development. During critical stages of development, preterm babies,
and neonates may be exposed to DEHP, a reproductive and developmental toxicant.
This occurs because of the ubiquitous presence of DEHP in their environment. The
multiple and relatively high exposures that can occur in the NICU are potentially
at or in excess of levels known to cause adverse health effects in relevant animal
studies.
"Since DEHP releases to vinyl products are not easily controlled, prevention
should be the primary management option" (Rossi, 2000). To ensure that our
patients are not exposed to DEHP, we will have to demand DEHP-free health care products,
particularly in those settings where our smallest and most vulnerable patients are
cared for. Using PVC-free products virtually assures that the product will be DEHP-free
because the other plastics rarely add DEHP. "In addition, PVC-free products
avoid the lifecycle hazards of vinyl, including the use of a known carcinogen to
manufacture vinyl (vinyl chloride monomer) and the downstream formation of dioxin
when vinyl is burned in a medical waste incinerator" (Rossi, 2000; Thornton
et al., 1996; Wagner and Green, 1993).
PVC is the most widely used plastic in medical products. It accounted for 27% of
all plastic used in durable and disposable medical products in the United States
in 1996 (Schettler et al., 2000). Approximately 445 million pounds of PVC were consumed
in the manufacture of intravenous (IV) and blood bags, tubing, examination gloves,
medical trays, catheters, and testing and diagnostic equipment in 1996. Tubing,
IV and blood bags, and gloves are the primary end-uses for PVC in disposable medical
products. Both patients’ health and safety, as well as the public’s health, are
of concern regarding PVC.
In January 2002, the Health Canada Expert Advisory Panel recommended that health
care providers not use DEHP-containing devices in the treatment of pregnant women,
breastfeeding mothers, infants, males before puberty, and patients undergoing cardiac
bypass, hemodialysis, or heart transplant surgery. They recommended the alternative
measures be introduced "as quickly as possible."
From 'Environmental Health in the Healthcare Setting,'
by Barbara Sattler, DrPH, RN
On the Web
Health Care Without Harm
U.S.FDA Public Health Notification on DEHP
www.fda.gov/cdrh/safety/dehp.html
