Mercury from maternal “silver” tooth fillings in sheep and human breast milk

Abstract

Neonatal uptake of mercury (Hg) from milk was examined in a pregnant sheep model, where radioactive mercury (Hg203)/silver tooth fillings (amalgam) were newly placed. A crossover experimental design was used in which lactating ewes nursed foster lambs. In a parallel study, the relationship between dental history and breast milk concentration of Hg was also examined in 33 lactating women. Results from the animal studies showed that, during pregnancy, a primary fetal site of amalgam Hg concentration is the liver, and, after delivery, the neonatal lamb kidney receives additional amalgam Hg from mother's milk. In lactating women with aged amalgam fillings, increased Hg excretion in breast milk and urine correlated with the number of fillings or Hg vapor concentration levels in mouth air. It was concluded that Hg 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.

Effect of teeth amalgam on mercury levels in the colostrums human milk in Lenjan

“…Levels difference depending on sampling place, time, and exposure levels of the mothers. Our result of mercury milk levels are compared with data from the literature; the mercury levels found in breast milk in the present study are quite high, and higher than those found in Germany by (Drasch et al Drasch et al (1998)), Vimy et al (1997) and Klemann et al (1990); Table 2.…”

“…These results were in a great extent compatible with other studies. Vimy et al (1997), Oskarsson et al (1996), Drasch et al (1998), Klemann et al (1990), Langworth et al (1991) and Ursinyova and Masanova (2005) detected significant differences in mothers milk mercury levels between mothers with and without amalgam-filled teeth.…”

“…Vimy et al (1997) have suggested that the placement and removal of amalgam in pregnant and lactating mothers could subject fetuses and neonates to exposure risks. Lindow et al (2003) reported that fetal hair-Hg was significantly higher in babies when their mothers had amalgam restoration procedures performed before or during pregnancy.…”

“…Estimates of amalgam mercury daily dose in humans have varied from 1.2 to 27 μg Hg/day, with a present consensus of approx 10-12 μg absorbed/day for the average person with eight colossally involved fillings (Lorscheider et al 1995;Vimy et al 1997).…”

Silver as biocides in burn and wound dressings and bacterial resistance to silver compounds

“…The slow release of Hg from amalgams is known to select for Hg-resistant bacteria in the gut [59]. Ag is also released [42] and Ag-resistant oral bacteria were recently reported [14].…”