Parenteral Nutrition as an Unexpected and Preventable Source of Mercury Exposure in Preterm Infants Karola Jering, MD1, Michael Aschner, PhD2, Amy Beller, RN3, Ellyn L. Hamm, MM, MT-BC3, Margaret Langdon, RRT4, and Nathalie L. Maitre, MD, PhD3,5 Perinatal mercury exposure has neurodevelopmental consequences, which may be worse in preterm infants. In our cohort (N = 60), maternal and infant prenatal exposures were low, but infant levels increased during hospitalization and correlated only with duration of parenteral nutrition. A non-negligible exposure resulted from the nutrition preparation on equipment shared with adult preparations. (J Pediatr 2015;-:---).

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ercury (Hg) is a ubiquitous pollutant in the environment and can be found in various forms such as elemental Hg vapor, methyl mercury (MeHg), or mercuric chloride. Hg is most toxic developmentally in one of its organic forms known as MeHg.1,2 When exposure to Hg occurs perinatally, it has toxic effects on the developing nervous system and may cause long-term deficits in cognition and behavior.1-5 Preterm infants have increased vulnerability to neurotoxic agents because of an immature blood-brain barrier and ongoing developmental processes. Nonoccupational exposure to Hg is primarily dietary in nature by bioaccumulation of MeHg in the aquatic food chain, but iatrogenic exposures in the form of dental amalgam,1,2 thimerosal-containing vaccines,6 and blood transfusions7,8 have been reported. We investigated Hg exposures of preterm infants in the neonatal intensive care unit (NICU) of a tertiary care institution. We hypothesized that Hg levels in neonates are related to maternal Hg levels and that infant Hg levels may rise if they are exposed to Hg through breast milk.

Methods This was a prospective observational study of 60 maternalinfant dyads in the Vanderbilt NICU in Nashville, Tennessee (January 1, 2010, through December 31, 2011). Infants of gestational age (GA)