Endocrine disruptors: Genetic, epigenetic, and related pathways

Endocrine-disrupting chemicals (EDCs) are a diverse class of natural and man-made chemicals. Exposure to EDCs is suspected to cause adverse effects on endocrine functions by interfering synthesis, transport, and/or degradation of endogenous hormones. The group of molecules, exerting endocrine disruption activities, is highly heterogeneous and does not correlate structurally to steroid hormones. Because of the possibility of exposure at low doses of multiple EDCs, delineating their mechanism of physiological endpoints of exposure at environmentally relevant concentrations is a challenge to toxicologists. Humans are constantly exposed to low levels of EDCs, in which most of the reported effects are linked to their interactions with nuclear receptor superfamily members and aryl hydrocarbon receptors that possess transcriptional (genomic) and non-genomic activities. These EDCs exert their epigenetic effects via methylation of DNA or alterations in microRNA expression. This chapter aims to articulate the genetic, epigenetic, and related pathways of man-made endocrine disruptors and discuss their consequences for human health.