Authors: Vipin Kumar Gupta and Preeti Gupta
So, what are Xenoestrogens? Before going to xenoestrogen; we have to know about estrogen. There are two regulatory systems in body; nervous system and endocrine system, which regulate the metabolic processes of our body. Endocrine systems plays a vital role in managing nutritional, behavioral, reproductive, growth, gut, cardiovascular and kidney function of the body. Hormones are chemical messengers, released into the bloodstream, secreted in the body by glands and tissues, coordinate multiple activities and maintain homeostasis. Body cell may be exposed to both endogenous and exogenous hormones, and hormone mimicking compounds. Estrogen is one of the hormones that promotes the development and maintenance of female sex characteristics. Xenoestrogens is the Xeno-hormone that imitates estrogen. Other synonyms are estrogen-like EDC’s (Endocrine Disrupting Compounds), Hormonally active agents, Environmental estrogen, Eco-hormones etc. They can pose a serious health hazards. It was defined by the U.S. Environmental Protection Agency (EPA) as an exogenous agent that interferes with synthesis, secretion, transport, metabolism, binding action, or elimination of natural blood-borne hormones that are present in the body and are responsible for homeostasis, reproduction, and developmental process (Evanthia et al., 2009).
Kinds of xeno-estrogens: There are two types, natural and synthetic. Natural xeno-estrogens are phyto-estrogen; plant origin, and myco-estrogen; fungi origin. Synthetic xeno-estrogens has two categories; one is deliberately manufactured estrogen analogues i.e pharmacological preparations, and second one, substances manufactured for a different purpose but have estrogen-like properties i.e. industrial, agricultural, other chemical preparations. Metallo-estrogens, an entirely new class of cancer-causing estrogens, which is inorganic in nature. In a report published in the Journal of Applied Toxicology, researchers found that metal can bind to cellular estrogen receptor and can mimic actions of physiological estrogens (Darbre, 2006).
Sources of xeno-estrogens: Chemical pesticides, contaminated water / cereals / fruits / vegetables / meat / dairy products and eggs, cosmetics and toiletries, plastics, households cleaners and nonstick kitchen wares, birth control pills, and spermicidal gels etc.
Potential mechanism of action: This is specific to the compound, one may affect multiple target cells by multiple mechanisms may be by: activating expression of the estrogen receptor in cell, via a genomic or non-genomic pathways, inhibition of steroid hormone synthesis, transport or metabolism, modulation of neurotransmitter receptors, modulation of immune responses, activating the aryl hydrocarbon receptor and / or other mechanisms like stimulation of sex hormone binding globulin synthesis, competitive inhibition of endogenous estrogen or none of the above.
Health effects of xeno-estrogens: Wildlife effects, numbers of female marine gastropods increased in invertebrates, reproductive abnormalities in fish, population of amphibians declines and deformed progeny, developmental abnormalities in reptiles, eggshell thinning and altered gonadal development in birds, reproductive; sperm concentrations and sperm motility and immune function reduced in mammals. Human health effects, Variable and specific target-organ effects, biological impact of xeno-estrogen found individually or in combination. Reproductive effects- Estrogen have profound effects on the development and function of reproductive organs.
- Precocious puberty
- Abnormalities of the male reproductive tract
- Fertility impairment
- Increase in spontaneous abortions
- Declining human sperm count and quality
- Affected sex ratios Neuro-behaviour; effects on neurological development (growth retardation, impairment of intelligence and emotional instability) Immune function; immuno-toxicity (reduced the level of T-lymphocytes, lowered resistance to infection) Childhood obesity Diabetes and glucose homeostasis Increasing trends of cancer; in hormonally sensitive tissues have been attributed, in part, to widespread exposure of the general population to xenoestrogens eg. breast cancer, endometrial cancer, prostate cancer, testicular cancer, thyroid cancer etc.
How can we detect them: GC/MS method, quantitative determination of EDCs (phenolic compounds) & estrogens by High Resolution GC− (NCI) −MS, pico gram per liter range.
Bio-markers: Total effective xeno-estrogen burden (TEXB), a biomarker of xeno-estrogen exposure in human. It can be separated by solid-phase extraction, followed by fractionation by HPLC. Vitellogenin, a bio marker for environmental estrogen in fish.
Conclusion: In the context of universal distribution of synthetic or anthropogenic estrogens, phyto-estrogens, myco-estrogen and metal-estrogens etc. it is essential to minimize exposure and maximize excretion, to preserve yourself, and able to lead a healthy life. And lastly “Go simple, Go green, Go natural and Go organic”!
Acknowledgement: I would like to express my gratitude to all those person who saw us through this article; to all those who provided support, talked things over, read, wrote, offered comments. Last and not least; I beg forgiveness of all, whose work has been with me during writing of this manuscript and their names I have failed to mention.
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7. Wikipedia / Xenoestrogen
About Author / Additional Info:
I am currently pursuing PhD in Veterinary Public Health & Epidemiology discipline.