Neonatal and Maternal Hair Zinc Levels in a Nonhuman Primate Model of the Fetal Alcohol Syndrome

Abstract

The role of zinc deficiency in the etiology of ethanol-associated fetotoxicity was assessed by measurement of maternal and newborn hair zinc content in a nonhuman primate model of the fetal alcohol syndrome. The model best approximates the human situation for length of gestation and type of placentation, coupled with the ability to control for nutritional factors. All moths received 110% of their minimum daily caloric requirements as a balanced, nutritionally complete diet, including a minimum of 3.5 mg zinc per day. Over a 2-year period, maternal hair samples from 17 pregnancies (using 12 females) were obtained at term. There were 16 live, full-term neonates (nine ethanol exposed and seven control) from whom samples were taken within 1 hr of birth. The ethanol-exposed infant monkeys had a significantly higher incidence of craniofacial dysmorphology and developmental delay compared to the controls. There was no difference in hair zinc levels between ethanol-exposed and control animals for either the mothers or the newborns. Neonatal levels were, however, consistently higher than corresponding maternal. Although the findings cannot exclude transient or early gestational zinc deficiency as a factor, they produce further evidence that ethanol (and/or its metabolites) is the proximate toxin in the type of fetal injury seen in the fetal alcohol syndrome.