Exposure of newborn infants to di-(2-ethylhexyl)-phthalate and 2-ethylhexanoic acid following exchange transfusion with polyvinylchloride catheters.

Infants in the neonatal intensive care unit are regularly exposed to the plasticizer di-(2-ethylhexyl)-phthalate (DEHP) following exchange transfusion or extracorporeal membrane oxygenation. Whether such exposure leads to increased morbidity is not known, although elevated levels of DEHP have been associated with necrotizing enterocolitis and cholestasis. The hypothesis that infants undergoing exchange transfusion are exposed to toxic levels of DEHP and the presumed metabolite 2-ethylhexanoic acid (EHXA) was tested by measuring serum levels of DEHP in 16 newborn infants (gas-liquid-chromatography) and urine concentrations of EHXA in 6 of these infants (gas chromatography-mass spectrometry). DEHP levels were undetectable (< 1 microgram/mL) before exchange but ranged from 6.1 to 21.6 micrograms per mL of serum (average, 12.5 +/- 6.2 micrograms/mL) after a single exchange transfusion. DEHP uptake did not result in cholestasis. EHXA peak levels were 127 to 416 ng per mL of urine, with a median of 174 ng per mL. Concentrations of EHXA were lower than anticipated, which indicates that EHXA is not a major metabolite in the neonatal infant.