Fetal and Neonatal Endocrine Disruptors

Abstract

Endocrine disruptors are substances commonly encountered in every setting and condition in the modern world. It is virtually impossible to avoid the contact with these chemical compounds in our daily life. Molecules defined as endocrine disruptors constitute an extremely heterogeneous group and include synthetic chemicals used as industrial solvents/lubricants and their by-products. Natural chemicals found in human and animal food (phytoestrogens) also act as endocrine disruptors. Different from adults, children are not exposed only to chemical toxins in the environment but may also be exposed during their intrauterine life. Hundreds of toxic substances, which include neuro-immune and endocrine toxic chemical components that may influence the critical steps of hormonal, neurological and immunological development, may affect the fetus via the placental cord and these substances may be excreted in the meconium. Children and especially newborns are more sensitive to environmental toxins compared to adults. Metabolic pathways are immature, especially in the first months of life. The ability of the newborn to metabolize, detoxify and eliminate many toxins is different from that of the adults. Although exposures occur during fetal or neonatal period, their effects may sometimes be observed in later years. Further studies are needed to clarify the effects of these substances on the endocrine system and to provide evidence for preventive measures.Conflict of interest:None declared.

Effects of Prenatal Exposure to Endocrine Disruptors and Toxic Metals on The Fetal Epigenome

“…In support of this, these compounds have been identified in cord blood together [16,110]. Thus, research focusing on exposure to a single contaminant does not adequately represent the true human experience.…”

“…Yet, few studies have been published that examine the effects of compound mixtures on the fetal epigenome, despite the fact that the chemicals reviewed here are often found within cord blood together [16,110]. Those that were identified examine interactions between compounds, such as DDT and PBDE, or how cumulative exposure to a group of varied chemicals, such as phenols, may correspond to epigenomic changes in the fetus [83,109,[111][112][113].…”

“…Toxic metals and endocrine disruptors are ubiquitously found in the environment and have been measured and quantified in the fetus, supporting that in utero exposure to these chemicals occurs [16,17]. Given the link between prenatal exposures to toxic metals, endocrine disruptors and diseases occurring later in life, epigenetic modifications are believed, at least in part, to underlie these effects [18].…”

Diethylstilbestrol decreased adrenal cholesterol and corticosterone in rats

“…Therefore, chronic corticosterone suppression induced by DES has the potential to disrupt the regulators of endocrine homeostasis and to facilitate the impairment of stress resistance. These findings constitute a new and important step towards understanding the mechanisms behind DES toxicity, such as reduced fertility, increased vaginal adenocarcinoma, and reduced testicular size and sperm count (Schrager & Potter 2004, Shin et al 2009, Unüvar & Büyükgebiz 2012. It is difficult to elucidate the mechanism of DES toxicity over the long term from the foetal stage to adulthood due to multiple hormone-related events such as foetal development, delivery and puberty.…”

Suppression of liver Apo E secretion leads to HDL/cholesterol immaturity in rats administered ethinylestradiol

“…The most investigated endocrine disruptor, diethylstilbestrol (DES), is a synthetic nonsteroidal estrogen used in the United States and Europe from the mid‐1940s to the 1970s for the prevention of spontaneous abortion and premature delivery. DES causes severe endocrine toxicities in human 4, 5, 6, 7, 8, 9, 10; however, the detailed mechanisms of action of DES are not well understood. DES has also been used for prostate cancer therapy in Europe after failure with initial hormonal therapy 11.…”