Endocrine disrupting chemicals (EDCs) are defined as exogenous chemicals or mixtures of chemicals that are able to interfere with the endocrine system, mimicking or antagonizing the hormonal activity. They can persist in the environment, because of their degradation resistance; in fact, the field of endocrine disruption is rooted historically in wildlife biology and reproductive endocrinology. Recently, EDCs have been implicated in metabolic syndrome and obesity. In this regard, our research group has investigated, by gas chromatography-mass spectrometry, the EDCs presence in brain samples of 24 stillbirths that were collected over a 3-year period (2012–2014) from the Northeast Italy, which is a notorious area that is devoted to apple cultivation.

Surprisingly, organochlorine pesticides and organophosphorus pesticides, well-known EDCs, have been detected in 11 fetuses whose mothers were obese and affected by gestational diabetes mellitus. More in detail, the following organochlorine pesticides and organophosphorus pesticides have been detected at parts-per-million concentrations: α-chlordane, γ-chlordane, heptachlor, p,p’-dichlorodiphenyldichloroethylene, p,p’-dichlorodiphenyltrichloroethane, chlorfenvinphos, and chlorpyrifos. Apart from the noteworthy evidence of pesticides’ bio-persistence, this finding implies a redefinition of the placental barrier concept: not a real safety system, but a time-deferral mechanism of absorption. The term placental barrier in fact refers to a 4-membrane structure that is made by 2 epithelial layers that exactly line the chorionic villi and by 2 endothelial layers that belong to the feeding vessels for the fetus. It is an effective barrier only for a low administration of water-soluble substances, which encounter obstacles to cross 4 instead of 2 membranes. High doses of water-soluble compounds can reach appreciable concentration in the fetal blood; the lipid-soluble chemicals, such as EDCs, are able to pass the placental barrier through a simple mechanism of passive diffusion, even in minimal concentrations. After crossing the placental barrier, our results show that they can also pass through the still immature blood-brain barrier of the fetus. All our EDC-positive stillbirths have shown a hypodevelopment/agenesis of ≥1 nuclei, which is assigned to the vital function control, in the central autonomic nervous system. For this reason, environmental EDCs should be sought systematically during autopsy to establish a possible correlation also with stillbirth.