The Impact of Prenatal Counseling on Lead and Mercury Levels

Abstract

Introduction

The Newark, NJ lead water crisis was publicized in 2016 when elevated levels were detected in Newark Public School buildings. Subsequently, the city of Newark removed and replaced over 23,000 lead service lines and provided free water testing and filters; thousands of lead lines remain. Elevated lead and mercury exposure is associated with both obstetrical and pediatric complications. An increased risk of stillbirth, spontaneous abortion, gestational hypertension, and preeclampsia have been observed. Impaired neonatal neurodevelopment, low birth weight, and increased infant mortality rates have been documented. Elevated lead levels can impact a patient’s ability to provide their infant with human milk exclusively. Given the negative maternal and fetal outcomes over a wide range of blood levels, the American College of Obstetrics and Gynecology has recommended that all pregnant patients undergo screening at the earliest prenatal encounter and that select pregnant patients with elevated risk undergo screening for lead. University Hospital, located in Newark, NJ, has been screening patients since 2019, and those with elevated levels of lead and mercury have been provided counseling to reduce exposure during pregnancy.

Methods

At University Hospital, lead (Pb) and mercury (Hg) screening are part of the standard prenatal labs performed at the initial prenatal visit. If the level of lead or mercury is elevated beyond the established reference range (Pb>3.5; Hg>5), the obstetrical team refers the patient for counseling with a nurse or nutritionist. A 23-question questionnaire developed by the NJ Department of Health is used to identify potential sources of lead and mercury exposure. Repeat lead and mercury levels were collected at admission for delivery for comparison.

Results

Over 22,000 samples (initial screenings and follow-ups) have been performed on University Hospital patients. One-quarter of patients tested had lead levels, and fifty percent had mercury levels in the range of potential health effects and above the desired cut-off limit. Initial results have shown that common sources of lead exposure included pipes and cookware, while consumption of fish and cosmetics and skin care products containing heavy metals were typical causes for elevated mercury. These patients subsequently underwent the recommended counseling. After the removal of toxic exposures during the pregnancy, reductions in lead and mercury levels were observed at the time of admission to labor and delivery. This reduction was also reflected in the newborn screening for lead and mercury.

Conclusion

Preliminary results demonstrate how dietary interventions and lifestyle modifications reduced lead and mercury levels in this patient population. A larger study in Newark and other similar populations across the country is recommended to confirm our findings. We will continue to work to identify other sources of heavy metal contamination and interventions that may improve health outcomes. It may be worthwhile correlating the lead and mercury levels with neighborhoods in the greater Newark area for targeted intervention and country of birth to determine the role of prior exposure, including childhood exposure, as many University Hospital patients were born outside of the United States.