Infants pick up toxic chemicals in intensive care

Science News, August 13, 2005 by Janet Raloff

Neonatal intensive care units routinely save the lives of extremely premature and critically ill newborns. Many of these successes are made possible by tubing and other equipment rendered flexible with a plasticizer known as diethylhexyl phthalate (DEHP). A new study finds that this equipment releases DEHP into the babies, though the impact on such children is still uncertain.

Everyone carries at least traces of phthalates, which are ubiquitous pollutants (SN: 2/22/03, p. 120). However, DEHP in neonates is a special concern because "it is a reproductive and developmental toxicant in laboratory animals," says study author Russ Hauser of the Harvard School of Public Health in Boston.

Hauser and his colleagues collected urine from 54 infants in intensive care. Tests at the Centers for Disease Control and Prevention in Atlanta turned up a metabolic breakdown product of DEHP in nearly every sample, the team reports in an upcoming Environmental Health Perspectives.

The researchers had logged all DEHP-containing equipment to which each child was exposed, including breathing and feeding tubes, lines carrying blood to an oxygenation machine, and catheters. Grouped into three levels of the children's exposures to plastics during intensive care, urine concentrations of the DEHP marker correlated with the extent of exposure.

Urine from the highest-exposure group contained five times the concentration of the marker as did urine from the least-exposed babies, and infants intermediately exposed to DEHP had medium concentrations of the chemical marker. The highest marker concentrations in the study were up to 20 times as high as those reported in studies in healthy toddlers. To date, no adverse impact has been reported among children with known exposures to DEHP.

Many plastic hospital products that are low in or devoid of phthalates are available, Hauser notes, adding that they might be particularly appropriate for infants in intensive care, who are "being exposed at a sensitive window" of development.