> Other common Endocrine Disruptors inlcude PFE, PFOAs (teflon coating
> on cookware, coats/clothing, furniture, carpets, floor polishes, etc).
Snipet from http://goliath.ecnext.com/coms2/summary_0199-5220746_ITM
Over past decades, a whole range of fluorinated chemicals have been
synthesized and used as wetting agents, lubricants, corrosion
inhibitors, insecticides, cosmetics, fire retardants, paper coatings,
and surfactants. The high stability of the carbon-fluorine bond and
the inert characteristics of most of these compounds are regarded as
attractive properties during the manufacture of plastics, electronics,
textiles, or construction materials. For a long time, these
fluorinated chemicals were considered metabolically inert and
nontoxic. However, environmental monitoring has shown that degradation
to persistent molecules does happen on a large scale, as deduced from
the worldwide distribution of compounds such as perfluorooctane
sulfonate (PFOS), perfluorooctanoic acid (PFOA),
perfluorohexanesulfonate, and perfluorooctanesulfonamide, for
instance, describe fluorotelomer alcohols as potential sources of
perfluorinated acids in regions as remote as the Arctic. Although the
fluorotelomer alcohols are known as volatile chemicals that are
capable of long-range atmospheric trans****t, biologic transformation
seems to be the major degradation pathway causing deposition of
mentioned perfluorinated acids. In addition, during past years many of
the perfluorinated compounds have been found to possess undesirable
toxic characteristics. As reviewed by Lau et al. (2004),
perfluoroalkyl acids and their derivatives can cause developmental
toxicity. Exposures of rats to PFOA may cause significant lags of
weight gain of the offspring and a statistically significant increase
in mortality in both male and female pups. PFOS exposure may provoke
weight loss, hepatotoxicity, and reduction of serum cholesterol and
thyroid hormones.
PFOS apparently is also able to affect the neuroendocrine system
(Austin et al. 2003). Female rats injected with PFOS have a disturbed
estrous cyclicity and increased serum corticosterone levels with
decreasing serum leptin levels. Increased norepinephrine
concentrations were found in the paraventricular nucleus of the
hypothalamus. The fact that perfluorinated chemicals may disturb the
endocrine system is worrying and deserves further investigation. It is
generally known that a well-functioning endocrine system depends on a
delicate balance of hormones and hormone receptors that interact to
provoke complex cellular signaling. Different environmental pollutants
act as hormone mimics, binding to specific hormone receptors or
indirectly interfering with hormone signaling. The consequence may be
irreversible damage to the reproductive system, especially when living
organisms are exposed during the embryonic stages of life (Degen and
Bolt 2000; Rosselli et al. 2000). Behavioral changes are another well-
known adverse effect of disturbance caused by endocrine-disruptive
chemicals (Schantz and Widholm 2001). Although disturbance of the
thyroid system seems to be provoked by specific perfluorinated
chemicals such as PFOS, their potential for estrogen-like properties
has not been re****ted until now. In the present study, we evaluated
the capacity of perfluorinated compounds to reinduce cell
proliferation of growth-arrested MCF-7 breast cancer cells. Using a
combination of the E-screen assay, cell cycle analysis, and gene
expression analysis of estrogen-responsive biomarker genes, we
demonstrate the estrogenlike properties of the fluorotelomer alcohols
1H,1H,2H,2H-perfluorooctan-1-ol (6:2 FTOH) and 1H,1H,2H,2H-
perfluorodecan1-ol (8:2 FTOH) in vitro.
|
