Pregnancy and Newborns Exposure Study: Measuring Mercury and Lead in Newborns

The Minnesota Biomonitoring Program and the University of Minnesota are collaborating on a study to measure mercury, lead, and other chemicals in newborns, and to learn more about how to do these types of studies.

Why are we doing this study? What will we learn?

The Minnesota Department of Health's (MDH) Mercury in Newborns in the Lake Superior Basin pilot study raised important questions about biomonitoring of newborns in Minnesota, and our Advisory Panel recommended further study. For example, we would like to know:

  • Are dried blood spots the preferred way to monitor mercury in newborns?
  • How do measurements that use dried heel-stick blood spots compare to measurements that use cord blood?
  • Can we measure other metals, such as lead, in the same blood samples?

Umbilical Cord Samples:
Most studies of chemical exposure in newborns have used umbilical cord blood, the standard way to measure late prenatal exposure. While umbilical cord blood samples allow a laboratory to identify and measure different forms of mercury for likely sources of exposure, collecting cord blood for biomonitoring can be costly, and is not a routine procedure.

Heel-stick Blood Spots:
Across the country, heel-stick blood spots are routinely collected from new babies for state newborn screening programs. The blood spots are tested for treatable health conditions that are not evident at birth. And if new mothers consent to additional testing, in accordance with state law, the spots provide a low-cost specimen for state biomonitoring. However, laboratory methods for measuring chemical exposure in newborn blood spots are new; only a few states have tried to measure them.

Pregnancy and Newborns Exposure Study

With the consent of pregnant women enrolled in the larger University of Minnesota study, The Infant Development and Exposure Study (TIDES), the Minnesota Biomonitoring Program and the University of Minnesota are collecting and measuring cord blood and newborn heel-stick spots as paired samples from approximately 50 newborns. The MDH Public Health Laboratory will analyze the samples.

The Pregnancy and Newborns Exposure Study is testing newborn spots against cord blood to verify blood spots as a reliable measurement of mercury in newborns. Cord blood is also being tested for lead and cadmium. And, as the newborn spots are too small to analyze for different forms of mercury, we are testing whether all or only some mercury in the umbilical cord blood is methyl mercury. This will provide useful information about likely sources of exposure.

How will we use this information?

When the study results are available, the Minnesota Biomonitoring Program will compare the findings from the paired heel-stick blood spots and cord blood specimens. We will consult with our Advisory Panel for recommendations about the preferred methods for future biomonitoring of newborns, and provide our findings on this web site in 2013. This information will help other states looking for methods to monitor exposure in newborns.

Will the babies' mothers receive the results?

Yes, the mothers who request their baby's results will receive the individual results of lead and mercury levels in the cord blood along with information about ways to prevent exposure in the future.

For questions or more information, Contact the MN Biomonitoring Program.

Tuesday, 29-Jan-2013 13:36:56 CST