Parabens, often suspected of being endocrine disrupting chemicals (EDCs), are commonly used as antimicrobial preservatives in many products (personal care products, food, and pharmaceutical products). Exposure to these substances during pregnancy could disrupt thyroid hormone homeostasis and potentially affect fetal growth.

The aim of this study was to identify paraben exposure profiles in the umbilical cord and to assess the impact of these substances on thyroid hormones in women giving birth. In addition, this work evaluates the potential link between possible sources of exposure and endogenous paraben concentrations.

A total of 154 pregnant women living in Algiers were recruited. Umbilical cord venous blood samples were taken immediately after delivery. Thyroid hormones (TSH, FT3, and FT4) were measured by electrochemiluminiscence. Parabens (MP, EP, and PP) were detected and determined by LC-MS/MS.

MP, EP, and PP were detected in 88.31%, 74.02%, and 85.06% of samples with mean concentrations of 1.42±1.08ng/mL for MP, 1.19±1.19ng/mL for EP, and 1.40±1.30ng/mL for PP. Exposure to EP was associated with an increase in TSH and a decrease in FT3 levels, whereas PP exposure was associated with a decrease in TSH and FT4 levels. Linear regression results showed several significant associations between paraben levels and general characteristics of newborns (gestational age, birth weight, and AGD in male). Analysis of potential sources of exposure to endocrine disruptors revealed a significant association between MP and EP concentrations and coffee consumption. A significant association was observed between EP levels and sunscreen use, and between PP levels and the use of Paraben-free shower gel. Finally, significant associations were observed between some household sources and parabens.

Prenatal exposure to parabens can interfere with the hormonal system, leading to potential complications during pregnancy.