TITLE:
Phthalate Metabolites in Amniotic Fluid and Maternal Urine Samples
AUTHORS:
Giovanna Tranfo, Enrico Paci, Daniela Pigini, Rossana Claudia Bonanni, Silvia Capanna, Caterina De Carolis, Sergio Iavicoli
KEYWORDS:
Chemical Exposure, Amniotic Fluid, Urine, Phthalate Metabolite, Glucuronic Acid
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.14,
November
20,
2014
ABSTRACT: The
objective of this study was to determine the concentrations of the metabolites
of four selected phthalates, widely used industrial chemicals which possess
endocrine-disrupting properties, in samples of amniotic fluid and maternal
urine collected in the same day, in order to verify if the latter can be
considered a measure of the fetal exposure. The quantitative determination of
the metabolites was carried out by HPLC-MS/MS with isotopic dilution from 70
pregnant volunteers. Detectable concentrations of phthalates metabolites were
found in amniotic fluids. As phthalate monoesters are excreted in the urine
conjugated with glucuronic acid, an enzymatic hydrolysis is carried out before
analysis. Amniotic fluids were tested with and without hydrolysis and only the
free phthalate metabolites, not conjugated with glucuronic acid, were found.
The concentration of metabolites after enzymatic hydrolysis in maternal urine is
not correlated to those of amniotic fluids, but the free form concentrations
are. These results suggest that only the free forms can cross the placenta. A
significant number of mothers showed urine phthalate monoesters concentrations
higher than non-pregnant women.