Distribution of melamine in rat foetuses and neonates

Pharmacokinetics of melamine has not been studied in pregnancies despite of the many reports on the effect on renal damage in adult and neonates. In this study, Sprague–Dawley rats have been used as a model to study the single-dose effect of melamine administration in late pregnancy and in neonates within 24 h. Melamine concentrations in maternal serum, breast milk, whole foetus, amniotic fluid, neonatal serum and neonatal kidney was measured by liquid chromatography coupled with mass spectrometry. Melamine was detected in all the samples, including foetal rats and amniotic fluid in utero. Melamine was able to pass through placenta and reach the foetus, and to accumulate in lactating mammary gland and neonatal kidney. Moreover, melamine was eliminated through the placenta of the foetus and the kidneys of the neonates, and later excreted into the amniotic fluid. The study characterised for the first time the distribution of melamine in foetuses and neonates, providing reference for toxicological study of melamine during pregnancy.