Human amniotic fluid was gained from 95 pregnant women by amniocentesis (group 1) and from 20 women during delivery (group 2). The concentrations of inorganic mercury in amniotic fluid as assessed directly by cold-vapor atomic absorption spectrophotometry (CV-AAS) averaged 0.29 +/- 0.1 microgram/l in group 1 and 0.86 +/- 0.25 microgram/l in group 2. Surface areas of dental amalgam fillings were also estimated in these women and ranged between 0 and 930 mm2. There was no correlation between the surface area of maternal amalgam fillings and the concentrations of inorganic mercury in amniotic fluid (r = -0.122 and -0.069, respectively). Furthermore, no positive correlation existed between amalgam fillings and the concentration of total mercury in maternal blood (4.48 +/- 2.33 micrograms/l) and in neonatal blood (3.28 +/- 1.57 micrograms/l) as measured by CV-AAS in group 2 (r = -0.4 and -0.12, respectively). Concentrations of total mercury were also measured by CV-AAS in the breast milk of 86 women, five to ten days after delivery. These concentrations averaged 1.9 +/- 1.6 micrograms/l and were also not significantly correlated to the maternal amalgam surface areas (r = 0.188). In conclusion, maternal amalgam fillings are of no importance for the mercury load of the fetus and the neonate.