Endocrine Disrupting Chemicals (EDCs)

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Endocrine Disrupting Chemicals (EDCs)
Lafayette College CE 372 Design II/Environmental
Site Assessment

• Slides provided by Cynthia Gulledge, University
  of Louisville, Kentucky

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Endocrinology study of hormones
General Features of the endocrine system
Transport
Gland
Hormone
Target Cell
rich blood supply
hormone receptors are very specific
secreted into the blood
ductless
can reach virtually every cell in the body
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Endocrine Glands
dont forget the heart, placenta, fat
All of these glands produce hormones and are also
targets for hormones
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ENDOCRINE SYSTEM
HORMONES Chemical Messengers Secreted By Glands
(pituitary, ovary, testis, adrenal) Into the
Bloodstream
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Chemical Confusion

• Environmental chemicals can trick or confuse the
  body into thinking they are natural body
  chemicals

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Symantec Confusion

• Endocrine disrupting chemicals (EDCs)
• Hormonally-active agents
• Environmental estrogens
• Environmental hormones
• Environmental chemicals
• Environmental signaling

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Functional or Receptor-Based Toxicology
McLachlan, J.A. 2001 Environmental Signaling
What Embryos and Evolution Teach Us About
Endocrine Disrupting Chemicals, Endocrine Reviews
22(3) 319-341.
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Sources of Hormonally-Active Compounds
Agriculture
Industry/Urbanization
Natural
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Sexual Differentiation in Mammals
Organizational Effect of Hormones
If something goes wrong with testis formation,
the rest of sexual differentiation is affected in
the male
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Take-Home Message
Reproductive abnormalities in wildlife and humans
Many hormonally-active compounds in environment
These compounds cause reproductive abnormalities
in lab
This evidence forms the basis of the endocrine
disrupter hypothesis