An updated review of environmental estrogen and androgen mimics and antagonists

[Guest guest]

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=PubMed & list_uids=9\

699867 & dopt=Abstract

J Steroid Biochem Mol Biol 1998 Apr;65(1-6):143-50 Related Articles, Books,

LinkOut

An updated review of environmental estrogen and androgen mimics and antagonists.

Sonnenschein C, Soto AM.

Tufts University School of Medicine, Department of Anatomy and Cellular Biology,

Boston, MA 02111, USA.

csonnenschein@...

For the last 40 y, substantial evidence has surfaced on the hormone-like effects

of environmental chemicals such as

pesticides and industrial chemicals in wildlife and humans.

The endocrine and reproductive effects of these chemicals are believed to be due

to their ability to:

1) mimic the effect of endogenous hormones,

2) antagonize the effect of endogenous hormones,

3) disrupt the synthesis and metabolism of endogenous hormones,

4) disrupt the synthesis and metabolism of hormone receptors.

The discovery of hormone-like activity of these chemicals occurred long after

they were released into the environment.

Aviation crop dusters handling DDT were found to have reduced sperm counts, and

workers at a plant producing the

insecticide kepone were reported to have lost their libido, became impotent and

had low sperm counts.

Subsequently, experiments conducted in lab animals demonstrated unambiguously

the estrogenic activity of these

pesticides.

Man-made compounds used in the manufacture of plastics were accidentally found

to be estrogenic because they fouled

experiments conducted in laboratories studying natural estrogens.

For example, polystyrene tubes released nonylphenol, and polycarbonate flasks

released bisphenol-A.

Alkylphenols are used in the synthesis of detergents (alkylphenol

polyethoxylates) and as antioxidants.

These detergents are not estrogenic; however, upon degradation during sewage

treatment they may release estrogenic

alkylphenols.

The surfactant nonoxynol is used as intravaginal spermicide and condom

lubricant.

When administered to lab animals it is metabolized to free nonylphenol.

Bisphenol-A was found to contaminate the contents of canned foods; these tin

cans are lined with lacquers such as

polycarbonate.

Bisphenol-A is also used in dental sealants and composites.

We found that this estrogen leaches from the treated teeth into saliva; up to

950 microg of bisphenol-A were retrieved

from saliva collected during the first hour after polymerization.

Other xenoestrogens recently identified among chemicals used in large volumes

are the plastizicers benzylbutylphthalate,

dibutylphthalate, the antioxidant butylhydroxyanisole, the rubber additive

p-phenylphenol and the disinfectant

o-phenylphenol.

These compounds act cumulatively. In fact, feminized male fish were found near

sewage outlets in several rivers in the

U.K.; a mixture of chemicals including alkyl phenols resulting from degradation

of detergents during sewage treatment

seemed to be the causal agent.

Estrogen mimics are just a class of endocrine disruptors. Recent studies

identified antiandrogenic activity in

environmental chemicals such as vinclozolin, a fungicide, and DDE, and

insecticide.

Moreover, a single chemical may produce neurotoxic, estrogenic and

antiandrogenic effects.

It has been hypothesized that endocrine disruptors may play a role in the

decrease in the quantity and quality of human

semen during the last 50 y, as well as in the increased incidence of testicular

cancer and cryptorchidism in males and

breast cancer incidence in both females and males in the industrialized word.

To explore this hypothesis it is necessary to identify putative causal agents by

the systematic screening of

environmental chemicals and chemicals present in human foods to assess their

ability to disrupt the endocrine system.

In addition, it will be necessary to develop methods to measure cumulative

exposure to (a) estrogen mimics, (

antiandrogens, and © other disruptors.

Publication Types:

Review

Review, Tutorial

PMID: 9699867 [PubMed - indexed for MEDLINE

========================

While not specifically addressing anti-aging, croning or veg science issues, the

effect of endocrine disruptors can

easily cast their effect wide enough for us all to be aware of their existence

in our food chains.

========================

Good Health & Long Life,

Greg ,

http://www.ozemail.com.au/~gowatson

gowatson@...