Assessing a New Method for Measuring Fetal Exposure to Mercury: Newborn Bloodspots.

Jessica W Nelson,Ruby H N Nguyen,Betsy L Edhlund,Zachary S Holmquist,Shanna H Swan,Christina E Rosebush,Jean Johnson

doi:10.3390/ijerph13070692

Abstract

Background: Measuring mercury in newborn bloodspots to determine fetal exposures is a novel methodology with many advantages. Questions remain, however, about its reliability as an estimate of newborn exposure to mercury. Methods: We studied mercury concentrations in paired bloodspots and cord blood from a convenience sample of 48 Minnesota women and infants. Results: The limit of detection for bloodspots was higher than for cord blood (0.7 and 0.3 μg/L in bloodspots and cord blood, respectively) with the result that mercury was detected in only 38% of newborn bloodspots compared to 62% of cord blood samples. The geometric mean mercury concentration in cord blood was 0.6 μg/L. Mercury concentrations were almost uniformly lower in bloodspots than in cord blood (mean ratio (±SD) = 0.85 ± 0.4), their mean value was significantly less than that for the cord blood (p = 0.02), and the two methods were highly correlated (r = 0.82). Conclusion: These preliminary findings indicate that newborn bloodspot mercury measurements have utility; however, until bloodspot analyses are more sensitive, they are likely to underestimate in utero exposure.

Highlights

Fetal exposure to mercury is a public health concern because even small amounts of mercury can damage the developing brain and nervous system [1]
We aimed to determine the association between total mercury in paired newborn bloodspots and cord blood in a convenience sample of women and infants from the Minneapolis/St
While mercury concentrations in paired newborn bloodspot andthat cord bloodofsamples were bloodspots than in the corresponding cord blood. This finding suggests that analysis of bloodspot specimens for mercury may systematically underestimate fetal exposure

Summary

Introduction

Fetal exposure to mercury is a public health concern because even small amounts of mercury can damage the developing brain and nervous system [1]. Mercury exposure may affect future learning abilities, memory, and attention, and lead to learning and behavioral problems later in life [1] Due to these adverse health effects, it is in the interest of local and state health departments to create methods of monitoring neonatal exposure to mercury for the purposes of identifying populations at risk, determining sources of exposure, and evaluating the need for targeted public health interventions. Compared to the standard measures of prenatal exposure that use cord blood or maternal blood, biomonitoring using bloodspots offers advantages of ease of collection and storage, as well as decreased cost. Due to these advantages, interest in using newborn bloodspots for biomonitoring is growing for a variety of exposures; recent. Conclusion: These preliminary findings indicate that newborn bloodspot mercury measurements have utility; until bloodspot analyses are more sensitive, they are likely to underestimate in utero exposure

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Conclusion