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Hormones
gone wild
Hormones
are essential to the regulation of tissue function, growth and
development, metabolism, and mood. Knowing this, it's easy to
appreciate the potential destructive effect on the body should
this crucial system ever be disrupted. This is why scientists
are becoming increasingly worried about the chemicals known as
"endocrine disruptors" that are found in everyday
hygiene and cosmetic products
The
human endocrine system is an important physiological network
comprised of glands and blood vessels that produce and
transport chemical messengers known as hormones around the
body.
These hormones are essential to the regulation of tissue
function, growth and development, metabolism, and mood.
Knowing this, it's easy to appreciate the potential
destructive effect on the body should this crucial system ever
be disrupted. This is why scientists are becoming increasingly
worried about the chemicals known as "endocrine
disruptors" that are found in everyday hygiene and
cosmetic products.
It's
not the presence of endocrine disrupting substances (EDS) in
our shampoos, toothpastes, anti-bacterial soaps, beauty
products, and, subsequently, our waterways that is causing
controversy. Rather, it is whether or not the levels of EDS we
are exposed to are high enough to have any effect.
 There
have been studies that have identified adverse biological
effects from EDS in animals, but whether this data can be
transferred to humans has been hotly debated by the science
community. Who is right, and are we exposing ourselves to any
number of serious health problems just for the sake of a
glowing smile and bacteria-free hands?
EDS
are exogenous (from outside the body) substances that not only
act just like hormones found in the endocrine system
(endogenous hormones), but also disrupt their normal
physiologic function. So what are some of the EDS under
suspicion? The National Institute of Environmental Health
Sciences (NIEHS) lists some chemicals that include a number of
the usual suspects. Known endocrine disruptors include
diethylstilbesterol (the drug DES), dioxin and dioxin like
compounds, PCBs and DDT. Based on animal studies, some other
suspect chemicals include Bisphenol A and various pesticides
and plasticisers.
Many
scientists claim that even low-level exposure is enough to
wreak havoc on any number of
hormone-related processes by interacting directly with our
hormone receptors; which can lead to cancer, reproductive
failure and developmental anomalies. They justify their claims
by drawing attention to the fact that endogenous hormones
naturally occur at quite small concentrations in the body, so
it follows that only small concentrations of exogenous
endocrine disruptors are needed to be harmful. If their theory
is correct, it makes hormonally active endocrine disruptors
much more potent than other types of toxic substances.
One
particular antibacterial compound called triclocarban (also
known as TCC or 3,4,4'-trichlorocarbanilide), used to enhance
the efficiency of bath soaps and other products, has been
under close scrutiny by researchers for a number of years now.
A University of California Davis study released in December of
2007 showed that soap containing triclocarban altered the
hormonal activity in rats and in human cells in the
laboratory.
In
the UC Davis study, the researchers identified a mechanism by
which the EDS interact with endogenous hormones in ways not
previously reported. They discovered that triclocarban
increases gene expression normally regulated by testosterone,
which led to abnormal prostate gland enlargement in rats that
were fed triclocarban. This is an important new finding, as
EDS were previously thought to only decrease, or block,
hormonal activity.
 Triclocarban
and other hormonally active substances are worryingly
ubiquitous; found in a myriad of everyday household products
such as body washes, bar soaps, wipes, cleansing lotions and
detergents. The NIEHS reports that as well as personal hygiene
products, EDS can also be found in plastic bottles, metal food
cans, detergents, flame retardants, floor coverings, food,
toys, cosmetics and household pesticides.
One
author of the UC Davis study speculates that regular exposure
to EDS may even explain some reproductive problems. "This
finding may eventually lead to an explanation for some rises
in some previously described reproductive problems that have
been difficult to understand," said Bill Lasley, a UC
Davis expert on reproductive toxicology and professor emeritus
of veterinary medicine.
Lasley
states, however, that more testing on EDS is required before
links can be made with any certainty, adding that the study
should not be used as a guide on whether or not to use
products containing triclocarban. "Our mothers taught us
to wash our hands well before the advent of antimicrobial
soaps, and that practice alone prevents the spread of
disease." 
There
are other common substances used in antibacterial soaps that
not only cause problems for the user, but also for the
environment. Triclosan is a very common disinfectant used in
antibacterial soaps that has been shown to produce a dioxin
when exposed to sunlight. While the resultant dioxin is
claimed to be of a very low-level, benign form, researchers
argue that it nonetheless gets into wastewater that is
eventually treated with chlorine.
Once
treated with chlorine the triclosan derived dioxin transforms
into a much more toxic species of dioxin.
"Repeated
exposure to chlorine, perhaps in water treatment facilities,
could chlorinate triclosan. After chlorinated triclosan is
discharged from the facility, sunlight could convert it into
more toxic dioxins. Such a process could be a source of highly
toxic dioxin in the environment," says Kristopher
McNeill, an assistant professor of chemistry at University of
Minnesota. "The disappearance of a pollutant such as
triclosan doesn't necessarily mean an environmental threat has
been removed," added co-researcher William Arnold.
"It may just have been converted into another
threat."
The
fact that such complex and long-term chain reactions can
ultimately result in dioxin - a powerful endocrine disrupting
substance - appearing in the environment shows how difficult
it is to keep track of these chameleon-like chemicals, let
alone what specific effects they may have on humans.
The
difficulties involved in demonstrating endocrine disruption in
humans from specific products mean that it is unlikely we will
get government warnings on bars of soap anytime soon. But the
science behind EDS research is sound, and nobody seems to
doubt the harmful effects that high levels of EDS can have on
humans. Whether health authorities continue washing their
hands of the problem remains to be seen.
|
go, go!
*Lower
stomach: Firm up your bikini belly with these abdominal
exercises. Starting by lying down on your back on the floor.
Place your hands under your buttocks for support. Slowly lift
and curl your legs toward you until your butt lifts slightly
off the floor. Stop and squeeze! Remember to go slowly and do
as many reps as you can. Aim for four sets. 
carcinogens, to suppressing the spread of tumors. ECGC is as
much as 100 times more powerful an antioxidant as vitamin C,
and 25 times more powerful than vitamin E. ECGC also may
account for the antibacterial properties of green tea. EGCG is
a powerful anti-oxidant: besides inhibiting the growth of
cancer cells, it kills cancer cells without harming healthy
tissue. 
other allergies, a study suggests. Researchers found higher
levels of a chemical linked to allergy in the blood of
children of stressed mothers. Levels were high even in those
who had not been exposed to high levels of dust mites, a
recognised allergies trigger. It is thought the risk of asthma
and allergy is controlled by a complex mix of genetic and
environmental factors. However, researchers suspect the impact
of these factors may also in some way be influenced by the
environment a foetus is exposed to while still in the uterus.
The Harvard team examined the theory that stress during
pregnancy can magnify the effect of foetal exposure to
substances, which can trigger allergy. Because even babies
exposed to low levels of dust mites in the uterus showed
elevated levels of IgE, the researchers concluded that stress
was amplifying their allergic response. 
biological cause for the dysfunction. The study compared
densities of elements of the serotonin and dopamine
neurotransmitter systems in the brains of 12 people diagnosed
with social anxiety disorder, but who had not taken medication
to treat it, and a control group of 12 healthy people. The
researchers used a radioactive compound that binds with
elements of the brain's serotonin and dopamine systems. It
revealed functional alterations in the thalamus, midbrain and
in the striatum (known to be acted upon by dopamine). The
altered uptake activity in these regions indicated a greater
level of disordered function. "Our study provides direct
evidence for the involvement of the brain's dopaminergic
system in social anxiety disorder in patients who had no prior
exposure to medication," said Dr Van der Wee, from the
Leiden University Medical Center. "It demonstrates that
social anxiety has a physical, brain dependent
component."