Endocrine Disruption

♂Endocrine Disruptors♀
Presentation Lecture by:By Sandy Poulos

Endocrine Disruption
* Endocrine System-a complex network of glands that produce and secrete the hormones that regulate all the major body functions.
* Endocrine Disruptor-chemical that interferes with the endocrine system to produce an undesired response, which may affect health, growth, and reproduction.

Mechanisms of Action
* Mimics
* Stimulators
* Blockers
* Endocrine flushers
* Enzyme flushers
* Destructors

EDCs
* Estrogens: any family of steroid hormones that regulate and sustain female sexual development and reproductive function
* Androgen: a class of male sex hormones related to the steroid androstane and produced in the adrenal cortex and the testes
* Substances mimicking feminizing effects are estrogenic and those mimicking masculinizing effects are androgenic
* Also anti-estrogenic and anti-androgenic

Classification
* Pesticides, herbicides, fungicides
* Polyaromatic compounds - PAHs
* Organic oxygen compounds (phthalates, bisphenol A)
* Surfactants
* Drugs
* Metals
* Phytoestrogens

Pesticide-DDT
* 1950’s to 1960’s – DDT
o Estogenic
o Affected reproduction system of birds
o Disrupted the eagle's endocrine system, interfering with calcium metabolism and produced weak egg shells, feminized frogs
o DDT metabolite (DDE) → anti-androgens
* Atrazine & Endosulfan

Bisphenol A & Phthalates
* Bisphenol A
o Used in the manufacture of some clear plastics (e.g. baby feeding bottles), and used in the resin which lines most tin cans
o Potency 4 to 6 times less than 17b-estradiol
+ Weakly estrogenic, anti-androgenic
* Phthalates
o Potency 6 to 7 times less than 17b-estradiol
+ Weakly estrogenic
Phthalates
Surfactants
Drug Example - DES
Sewage Treatment
Metals
Organotins
EDCs in Cosmetics & Toiletries
Parabens?
Dioxin
Phytoestrogens
Isoflavones
Soy-based specialty formula
Lignans
Precocious Puberty
Fertility in Danger ?
EDCs & People
References

Endocrine Disruption.ppt