Maria Helena Guerra Andersen1, Giuseppina Zuri2, Lisbeth E Knudsen2, Line Mathiesen3. 1. Department of Public Health, Section of Environmental Health, University of Copenhagen, Øster Farimagsgade 5A, DK-1014, Copenhagen K, Denmark; The National Research Centre for the Working Environment, Lersø Parkalle 105, DK-1014, Copenhagen Ø, Denmark. 2. Department of Public Health, Section of Environmental Health, University of Copenhagen, Øster Farimagsgade 5A, DK-1014, Copenhagen K, Denmark. 3. Department of Public Health, Section of Environmental Health, University of Copenhagen, Øster Farimagsgade 5A, DK-1014, Copenhagen K, Denmark. Electronic address: lima@sund.ku.dk.
Abstract
INTRODUCTION: Parabens are a group of chemicals widely used as preservatives in daily consumer products such as cosmetics, food items, pharmaceuticals and household commodities. They have been broadly detected in human samples indicating a general human exposure, and concerns arose from their potential endocrine disrupting effect. Especially the exposure to parabens during pregnancy is concerning, as the time of fetal development is a particularly vulnerable period. The aim of this study was to investigate the transport and metabolism of four commonly used parabens: methyl-, ethyl-, propyl- and butylparaben (MeP, EtP, PrP and BuP) and the metabolite para-hydroxybenzoic acid (PHBA) across the human placenta. METHODS: An ex-vivo human placental perfusion model was used. The test compounds were added in the maternal compartment (with initial concentrations of 1 mM or 0.1 mM). Placental transport was evaluated by fetal-maternal concentration ratios (FM-ratio), transport index (TI) and indicative permeability (IP). RESULTS: Information about parabens kinetics was taken from 10 perfusions and PHBA from 7 perfusions. Paraben metabolism was not detected. The placental transport of MeP, EtP, PrP, BuP and PHBA revealed a transfer from maternal to fetal circulations with FM120 of 0.86 ± 0.27 (MeP), 0.98 ± 0.28 (EtP), 1.00 ± 0.28 (PrP), 1.12 ± 0.59 (BuP) and 0.82 ± 0.37 (PHBA). The test substances accumulated in the perfused tissue in some degree. The average kinetic parameters FM-ratio, TI and IP were not different between chemicals. DISCUSSION: The present study shows that the placenta barrier is permeable to all four parabens and the metabolite, which implies potential fetal exposure.
INTRODUCTION: Parabens are a group of chemicals widely used as preservatives in daily consumer products such as cosmetics, food items, pharmaceuticals and household commodities. They have been broadly detected in human samples indicating a general human exposure, and concerns arose from their potential endocrine disrupting effect. Especially the exposure to parabens during pregnancy is concerning, as the time of fetal development is a particularly vulnerable period. The aim of this study was to investigate the transport and metabolism of four commonly used parabens: methyl-, ethyl-, propyl- and butylparaben (MeP, EtP, PrP and BuP) and the metabolite para-hydroxybenzoic acid (PHBA) across the human placenta. METHODS: An ex-vivo human placental perfusion model was used. The test compounds were added in the maternal compartment (with initial concentrations of 1 mM or 0.1 mM). Placental transport was evaluated by fetal-maternal concentration ratios (FM-ratio), transport index (TI) and indicative permeability (IP). RESULTS: Information about parabens kinetics was taken from 10 perfusions and PHBA from 7 perfusions. Paraben metabolism was not detected. The placental transport of MeP, EtP, PrP, BuP and PHBA revealed a transfer from maternal to fetal circulations with FM120 of 0.86 ± 0.27 (MeP), 0.98 ± 0.28 (EtP), 1.00 ± 0.28 (PrP), 1.12 ± 0.59 (BuP) and 0.82 ± 0.37 (PHBA). The test substances accumulated in the perfused tissue in some degree. The average kinetic parameters FM-ratio, TI and IP were not different between chemicals. DISCUSSION: The present study shows that the placenta barrier is permeable to all four parabens and the metabolite, which implies potential fetal exposure.