Heavy metals in human amniotic fluid: a pilot study

Objective: Many heavy metals are essential nutrients for a healthy life. However, significant evidence supports prolonged prenatal exposure as a risk factor for several adverse health effects. The aim of this study is to evaluate the presence of heavy metals in human amniotic fluid (AF) to demonstrate that there is an early fetal in utero exposure. Methods: The concentrations of a variety of heavy metals, including Be, Ag, Ba, Pb, U, Hg, Sr, Cu, Mn, V, Pd, Sn, Sb, Te, Pt, Sc, Tl, Ni, As, Co, Zn and Se, were measured in 25 AF samples obtained from amniocentesis between 15 and 18 weeks of gestational, after informed consent. Results: Be, Ag, Ba, Pb, U, Cu, Sr, Mn, V, Sn, Te, Pt, As, Tl, Sb, Co, Se and Zn concentrations were detected in measurable amounts in second trimester AF. Mg levels are elevated in all samples. Pd, Ni, Sc and Hg concentrations are below the detection limits in all samples. Conclusion: This study demonstrates that heavy metals pass into and accumulate in AF from a very early stage of gestation. Other studies are needed to evaluate the long-term health effects of this early exposure.