Neonatal Urine and Cord Blood Metals Analysis in a Cohort

摘要

Adverse health effects from environmental exposure to heavy metals is well-documented. Specifically, uranium exposure has been associated with adverse effects to the kidneys and urinary system in humans and developmental toxicity in animals. However, there is no information on neonatal urine uranium body burden levels and limited information on cord blood metal levels in neonates in the US. Matched neonatal urine (N=546) and cord blood (N=315) samples from the Global Alliance to Prevent Prematurity and Stillbirth (GAPPS) biorepository were analyzed for 15 elements in urine, including uranium, and five elements in whole cord blood, including cadmium, manganese, lead, selenium, and mercury (total). Urinary uranium and lead had higher geometric means, 0.087 pg/L (95% CI: 0.080 - 0.094) and 0.808 pg/L (95% CI: 0.756 - 0.864), respectively, in comparison with NHANES 2015-2016 geometric means for 3 to 5 year olds, 0.009 pg/L (95% CI: 0.007 - 0.11) and 0.590 pg/L (95% CI: 0.532 - 0.654), respectively. For the cord blood samples, lead had a lower geometric mean, 0.254 pg/dL (95% CI: 0.236 - 0.273), in comparison with the NHANES 2015-2016 geometric mean for 1 to 5 year olds, 0.758 pg/dL (95% CI: 0.675-0.850) and is less than the CDC reference value of 5 pg/dL. Blood mercury had a higher geometric mean, 0.670 pg/L (95% CI: 0.612 - 0.732), in comparison with the NHANES 2011-2012 geometric mean for 1 to 5 year olds, 0.262 pg/L (95% CI: 0.237-0.291). Note that the detection of chemicals in neonatal urine or cord blood indicates exposure but does not by itself indicate adverse health effects. Detection of elements may also be an indication of contamination in collection supplies, which were not pre-screened in this study. However, these results will fill existing data gaps and increase our knowledge about heavy metal exposures levels in neonates.