Vimy MJ, Hooper DE, King WW, Lorscheider FL. Mercury from maternal “silver” tooth fillings in sheep and human breast milk. Biological Trace Element Research. 1997 Feb 1;56(2):143-52.
It was concluded that Hg [mercury] originating from maternal amalgam tooth fillings transfers across the placenta to the fetus, across the mammary gland into milk ingested by the newborn, and ultimately into neonatal body tissues. Comparisons are made to the U.S. minimal risk level recently established for adult Hg exposure. These findings suggest, that placement and removal of “silver” tooth fillings in pregnant and lactating humans will subject the fetus and neonate to unnecessary risk of Hg exposure.