FDA Report Identifies DEHP Exposure Risks
In a report released in September 2001 and publicized to health care providers this past July, FDA concluded that newborn male infants and prepubertal boys with prolonged exposure to DEHP may be at risk for testicular abnormalities.
Because little data exist on the effects of DEHP exposure in humans, the report relied on information from animal studies linking DEHP exposure to adverse effects. In rodents, adverse effects are readily apparent in the testes, and the report described these glands as "particularly sensitive to DEHP."
The Environmental Protection Agency has classified DEHP as a probable human carcinogen based on findings from animal studies.
Using a conservative approach, FDA calculated that DEHP exposure levels should not exceed 0.6 mg/kg/day through the parenteral route or 0.04 mg/kg/day orally. DEHP is known to leach out of plastics, posing an exposure risk for patients who come into contact with DEHP-containing products. Multiple treatments in a neonatal intensive care unit, for example, might expose a critically ill newborn to at least 20 times as much DEHP as FDA deems safe.
Medical devices that may contain DEHP include i.v., blood, dialysis, and infusion bags and tubing; nasogastric tubes; and tubing used in cardiopulmonary bypass, extracorporeal membrane oxygenation (ECMO), and hemodialysis.
To avoid exposure to unsafe levels of DEHP, FDA recommends that DEHP-free devices be used for procedures that seem to carry the greatest exposure risks for vulnerable patients. Patients should not, however, forgo necessary medical procedures simply because of the risk of DEHP exposure.
The report noted that 0.9% sodium chloride injection and crystalloid fluids packaged in polyvinyl chloride bags pose "little to no risk" of DEHP exposure to patients. Likewise, little DEHP was found to leach into i.v. admixtures of drugs that have been solubilized in a pharmaceutical vehicle in accordance with the manufacturer's instructions.
Although infants and young males likely face the greatest health risks from exposure to DEHP, the report cautioned that the chemical could be harmful to anyone who is exposed to excessive amounts of it. Patients other than infants and young males who are likely to be at risk for excessive DEHP exposure include those requiring enteral nutrition or undergoing ECMO or cardiopulmonary bypass. Also, breastfed infants whose mothers undergo hemodialysis may be exposed to unsafe levels of the chemical.
The potential exposure risks from DEHP in medical devices became public in 1999 with the release of a report from the advocacy group Health Care Without Harm. The organization has called for hospitals to phase out DEHP-containing devices, saying that the chemical can harm the heart, liver, and kidneys as well as the male reproductive system.
The American Medical Association House of Delegates passed a resolution last December calling for the organization to urge FDA to expedite an evaluation of alternatives to DEHP and study ways to lessen patients' risk of DEHP exposure.
In a report issued this past January, an advisory panel for Health Canada recommended that DEHP-free products be used to perform ECMO or administer total parenteral nutrient solutions to newborns and prepubertal males. The report also advised against the use of DEHP-containing devices during cardiopulmonary bypass, hemodialysis, and certain other procedures and for the administration of lipophilic drug formulations.