Chapter 9 - Hormones-active substances

Abstract

Hormone-active substances are those compounds which behave like hormone activity, irrespective of mechanism. Hormone system is controlled by endocrine system in organism's body; therefore, they are also called as endocrine-active substances (EASs). Endocrine system, important communication system, comprises of endocrine glands that secrete “hormones” in blood stream (in response to stimulus) to regulate body function. Endocrine-disrupting chemicals disturb inadvertently the complex communication system and interfere with synthesis and secretion of bodily hormones. Endocrine substance influences the regular activity hormones. If these substances cause negative change in body, then they are also called endocrine disrupters. Endocrine disruptors are exogenous substances or mixture of substances that alter functions of endocrine system that eventually cause adverse impact on health of intact organism, its progeny, and subpopulations. Endocrine disrupters/EASs affect the health of exposed human and animals by entering into ecosystem via different sources. EAS could be naturally occurring (like phytoestrogen in soya) or synthetic. The artificially or synthetic EASs are man-made such as pesticides, dioxins, PCBs, Biphenyl A, and other environmental pollutants. Endocrine disrupters are also considered as environmental micropollutants or toxins that could harm the organism's health. These disrupting toxins (chemicals) could affect the endocrine system and cause diseases and dysfunctions across the whole life span of organisms. They are omnipresent, so they enter into body via different sources and pathways. Some environmental toxins are heavy metals, dioxins, pesticides, and polychlorinated biphenyl and other atmospheric pollutants (ozone, smog). The severity of effects on exposed organisms depends on dose-response relationship. The amount or concentration of dose is proportional to effect. These EASs induce toxic impacts on animals and plant's health by entering into food chain. In this chapter, different toxic impacts of hormone-active substances on animals, plants, and human health are mentioned in detail.