Introduction
Our modern
day 'chemical wonderland' has turned into a
'chemical nightmare' and few examples are more
startling than those caused by the hormone
disrupting artificial chemicals flooding our
environment.
These
troublesome chemicals go by many names such as
Endocrine Disruptor Chemicals (EDC), hormone
impostors, sex-hormone pollution and gender-benders
because they distort the reproductive organs of
animal life. The pharmaceutical industry
deliberately produces chemicals that affect these
systems for medical reasons while the chemical
industry does it accidentally; but neither one is
willing to take any responsibility for the
unintended consequences of their products.
But first
some definitions. Within the human body the
endocrine system includes important organs and
tissues that produce and store hormones. These
hormones are released directly into the
bloodstream and act as signals to activate and
regulate metabolism, reproductive system and
other critical functions. So an endocrine
disruptor would be a substance that interferes,
damages or disrupts this natural process.
Endocrine disruptors are sometimes called
environmental hormones because they are present
in the environment either naturally or from
artificial sources i.e. pollution.
Endocrine
disrupters are man-made chemicals which mimic
those of the body's hormonal system and
potentially interfere with human and animal
reproduction or development. [9]
Sex
hormones are chemicals that affect the functions
and development of the reproductive system.
Environmental estrogens are those that mimic
natural estrogen hormones. Environmental
estrogens are chemicals that act like estrogen
hormones in living organisms and are omnipresent
within the environment. Furthermore, some
chemicals actually block the process entirely and
are called anti-estrogen (or anti-androgyn as
applicable) compounds. Further complicating the
picture, different chemicals can have different
effects at the various life stages as well as on
different species.
Many of the
interactions within and between these chemical
regulated bodily systems depend on fairly simple
chemicals - all potential targets for imitation
by artificial and natural substances in large
quantities.
Points to
Ponder
-
Known
Endocrine Disruptor Chemicals (EDC's)
were first manufactured in the
1930s.
-
Testicular
cancer is the most common form
affecting young men and the
incidences of which have
increased three times over the
last 30 years in Britain alone.
-
River
and shore fish from Japan to
England have gender problems,
mostly feminized traits, and the more
they test for it the more it is found. It's not absolutely clear how
much this is affecting
reproduction rates for the fish
if at all, regardless it's not a
sign of health.
-
Phthalates
for example and other chemical
hazards are so ubiquitous that
their presence in the lab
equipment has to be factored out
of the studies!
-
Endocrine
disrupting chemicals can reduce
the effectiveness of the immune
system. The capacity for immune
response is determined early in
development, so damage early in
life will persist.
-
Artificial
hormones versus synthetic: "Ms.
Kidd says both natural and
synthetic estrogen go into the
sewage system in urine, but
bacteria take longer to break
down the synthetic version, which
means more of it gets into the
fish."
[1]
-
"Britain's
water companies have other
problems. They have carried out a
large program of water pipe
renewal. To cut costs existing
pipes have been lined inside with
plastic rather than being dug up
and replaced. This involved the
use of epoxy resins containing
bisphenol-A, another EDC, to
harden the plastic."
Where else have these chemicals
been added into the water pipes?
|
Artificial versus
synthetic hormones
There
is a difference between the artificial version
and the natural version of estrogenic compounds.
The natural ones are safer and break down in the
environment quicker but overexposure to either
one can cause health and reproductive problems.
Estrogens in any form are very powerful
chemicals and human and animal bodies are finely
tuned to respond to very small amounts of these
chemicals.
The
natural hormones, including plant produced
phytoestrogens, have brief life spans and do not
accumulate in tissue. They are easily broken down
in the human body and usually remain in the
bloodstream minutes or hours until broken up in
the liver.
Artificial
estrogens on the other hand are persistent and
difficult to breakdown. These chemicals have an
affinity for fat molecules and will accumulate in
body fat tissue over time. They can also be
passed on and accumulated through the food chain
process of predator and prey. Combinations of some
synthetic estrogens can create synergistic
effects. Thus the environmental pollution
cocktail may be benign in separate compounds but
have damaging effects when mixed together.
Sources of EDCs and Sex-Hormone
Pollution
Estrogenic
chemicals are known to be present in...
-
pesticides
(DDT is one notable example) /
insecticides / herbicides /
fungicides
-
products
associated with plastics (bisphenol
A, phthalates).
-
migration
from food can linings (bisphenol
a) and plastic packaging (phthalates)
[3]
-
pharmaceuticals
(birth control pills, hormone
medications, cimetidine, DES)
-
ordinary
household products (the breakdown
product of detergents and
associated surfactants, including
nonylphenol and octylphenol)
-
industrial
chemicals (polychlorinated
biphenyls (PCBs), dioxin and
benzo(a)pyrene)
-
also,
effects caused by heavy metals (lead,
mercury, cadmium, etc.)
|
Household detergents
Perhaps the
most significant source of artificial hormone
pollution comes from detergents.
|
Half of
common household detergents in Taiwan
contain hazardous endocrine disrupters
and most of them end up in the country's
rivers, researchers of the National
Science Council (NSC) said yesterday.
These
disrupters have polluted the water in
some rivers because of lax regulations
set for the quality of sewage effluent.
Ding Wang-hsien,
an analytical chemist at National Central
University [Taiwan], analyzed 90 common
household chemical products, including
laundry detergent, dishwashing detergent,
toilet cleaner, car cleaner and glass
cleaner.
Results
showed that 42 percent of laundry
detergents, 57 percent of dishwashing
detergents and 48 percent of toilet
cleaners contain nonylphenol ethoxylates
(NPEO), which break down into a group of
toxic and persistent byproducts, such as
nonylphenol (NP).
Ding said
the threat posed by endocrine disrupters
currently lurks at the fringe of public
awareness in Taiwan.
"The
invisible devastation deserves more
attention from the government," Ding
said, adding that a Cabinet-level inter-department
discussion, which included environmental,
health and agricultural agencies, was
necessary to trace and regulate endocrine
disrupters. [9]
|
Cosmetics
|
Kim Erickson
believes the adverse effects of toxins is
compounded over decades, confusing
hormone receptors and slowly altering
cell structure. Chemicals are transmitted
into the bloodstream in a number of ways:
powders have the least absorption, while
oily solutions or those designed to
increase moisture allow more of the
chemical to be absorbed.
Unlike food
or drugs, cosmetics and their raw
ingredients are not subject to review or
independent pre-market approval.
Erickson
admits it is too early to know with
certainty how serious the long-term
impact could be on health, but warns that
hormone-disrupting chemicals may lurk in
cosmetics which could lower immunity to
disease and cause neurological and
reproductive damage. 'Many of these same
ingredients have been found to cause
cancer in laboratory animals,' she said.
'At best, a visit to your neighbourhood
cosmetic counter could result in
allergies, irritations and sensitivities.' [10]
|
Birth Control Pills
& Hormone (replacement therapy for example)
drugs
Women who take birth
control pills or hormone therapy are flushing
enough hormones down the toilet to make male fish
downstream produce eggs, a Canadian study shows. [1]
Nature
Phytoestrogens
occur naturally in plants such as clover,
soybeans and other legumes, whole grains and many
fruits and vegetables.
There
is no doubt that each of us are exposed to these
chemicals on a daily basis, no safe place exists
and even if they were totally discontinued now
they would still reside in body tissues, and in
the environment for decades. The issue is how
much exposure is occurring and how much damage is
this causing to humans, animal life and the
environment in general.
Effects
Striking
effects of sex-hormone pollution have been
detected in aquatic life, especially river and
shore fish most likely from waste water runoff.
|
Karen Kidd
of the federal Department of Fisheries
and Oceans introduced synthetic hormone
from birth control pills into a remote 34-hectare
lake in northwestern Ontario, west of
Dryden. The male lake trout, white
suckers, fathead minnows and pearl dace
turned up this fall with proteins that
females use to manufacture egg cells, and
in some cases with the eggs themselves.
The lake
experiment used the amount of hormone
that would come from 6,000 women taking
the pill, she said.
The question
now is whether this feminization is
affecting the population size or
sustainability," she said. "Can
males with eggs in their testes reproduce
effectively? Can they contribute to the
population?"
It will take
another summer of adding chemicals, and a
couple of years of counting fish
afterwards, to know the full effects. [1]
Hormone
disrupters threatening the survival of
animal populations are also jeopardizing
the human future. At levels typically
found in the environment, these chemicals
act like mug the messengers or
impersonate them. They jam signals. They
scramble messages. The process that
unfolds in the womb and creates a normal,
healthy baby depends on getting the right
hormone message to the fetus at the right
time. Relatively low levels of
contaminants that have no observable
impact on adults can have a devastating
impact on the unborn. To date,
researchers have identified at least 51
synthetic chemicals--most of them
ubiquitous in the environment--that
disrupt hormones in one way or another.
Some mimic estrogen, and others interfere
with other parts of the body's control or
endocrine system, such as testosterone
and thyroid metabolism. This tally of
hormone disrupters includes large
chemical families such as the 209
compounds classified as PCBs, the 75
dioxins, and the 135 furans. It also
includes the most heavily used pesticide
in American agriculture, atrazine, and
the infamous DDT. [4]
|
Sperm Count
The
mechanism for how EDCs disrupt fertility is
poorly understood but one study may have found a
start.
"Everyday
substances in the environment directly
affect the ability of sperm to fertilise
an egg by triggering the premature
release of a chemical cocktail that sperm
cells use to penetrate the egg's outer
layer, a study has found."
"These
findings could be important in
understanding how different compounds,
known to be present in our environment,
might affect sperm function in humans.
Given that the environmental oestrogens
are very potent and that we are probably
being exposed to several at the same
time, it is important to know whether
they might have cumulative effects,"
Professor Fraser said. [8]
|
Early Puberty
Sex-hormone
pollution problems have been studied in Taiwan as
already mentioned, but another crowded island
seems to have even worse problems in this regard.
Puerto Rico has served as a prime case study
because of its exceedingly high rates of early
puberty. Although answers are still inconclusive
the debate focuses on chemical pollution and/or
diet. Either way these rates of early puberty,
which are actually increasing worldwide, have a
racial connection. "More striking, 27%
of black girls and 7% of whites develop these
early puberty signs at age 7 the second
grade according to a landmark puberty
study." [5] Why this is remains
uncertain, but at least one case of early puberty
symptoms were linked to a brand of shampoo, and
once discontinued the effects reversed. The
racial connection here is that since black people
have different hair than whites, they use
different hair care products - thus explaining
why only black women were being adversely
affected. Bovine growth hormones have also been
listed as a potential cause of distorted human
development in Puerto Rico and maybe elsewhere
too. This most likely occurred from eating the
wrong meat or too much meat.
But the
main focus of concern are those chemicals called phthalates again and the
higher than normal levels found in a test done on
Puerto Rican girls. Fetal exposure could be
causing early puberty but cosmetic and chemical
industries are adamant that none of their
products are causing these negative effects.
Other
issues to investigate include the potential for a
genetic predisposition to early puberty.
Also,
a genetic predisposition of Puerto Rican girls
for developing premature thelarche is unlikely.
Investigation among this ethnic group in the
Philadelphia, Pennsylvania, area did not reveal a
similar pattern of early sexual development (8).
Moreover, other ethnic groups living in Puerto
Rico are also affected by the condition (8).
In 1987, the Puerto Rico Department of Health
created by law the Premature Thelarche and Early
Sexual Development (PTESD) Registry in response
to the observed increase in cases (9).
This is the only world registry created for the
study of premature sexual development in a human
population. [6]
Fat could be another
cause
|
Nobody knows
what's causing the shift. Fat is the
leading theory, because childhood obesity
has doubled in the last 20 years and body
fat certainly can spur hormones. Some
scientists are hunting environmental
culprits, and point to a small study from
Puerto Rico where early breast
development is such a problem that it can
begin at the stunning age of 2
that casts suspicion on certain chemicals
in cosmetics and plastics. Age of
menstruation, which dropped from about
age 17 in the 19th century to between
ages 12 and 13 by about 1960, is holding
steady.
Fat is the
top theory. The fatter you are, the more
your body can convert adrenal hormones
into the female sex hormone estrogen.
Overweight children's blood harbors more
insulin, which also influences maturation.
Scientists even are studying whether the
protein leptin, produced by fat cells,
influences glands that produce sex-related
hormones. [5]
|
Interestingly enough
the primary fat culprit emerging from the latest
research is high fructose corn syrup, usually the
second ingredient by volume in carbonated soda-pop
drinks after water, as well as numerous other
junk-food items. A sedentary lifestyle coupled
with massive intake of
soft drinks is the most likely culprit for
childhood obesity.
Other
studies have shown that puberty may be arriving
earlier for American boys as well and that it may
lead to higher rates of testicular cancer and
other hormonal ailments already being charted
within the general population.
Early
puberty is a tricky issue and difficult to
adequately measure especially the physical
aspects in males for cultural reasons and because
it can be a 'subjective' phenomenon.
Other possible causes should be examined as well
and may include increased fat intake.
Timing Factors
Timing of
exposure to sex-hormone pollution is an important
factor in causing damaging effects. Body
sensitivity to sex-hormones occurs at certain
periods in life-cycle development.
|
The
development of the testis occurs almost
entirely during early development in the
womb. It is in this period that the
Sertoli cells differentiate, and any
exposure to oestrogen at this time
reduces the number of Sertoli cells
produced (Jensen et al., 1995). The
Sertoli cells are responsible for
producing sperm in later life, and it has
been shown that the number of Sertoli
cells is directly related to the sperm
count, so fewer cells will lead to a
lower sperm count (Jensen et al., 1995).
It is also believed that abnormal germ
cells, formed in early development, are
responsible for most testicular cancers
in later life (Jensen et al., 1995).
The
oestrogen diethylstilbestrol (DES) was
given to > 5 million pregnant mothers
in the period between the late 1940s and
the early 1970s to prevent miscarriage.
Its use was stopped after a high
incidence of a rare cervical cancer in
pubertal girls exposed to DES in the
uterus. It was later found that male
offspring also had a higher level of
reproductive abnormalities, including low
sperm counts (Jensen et al., 1995). The
case of DES is a clear indication that
exposure of the foetus to external
oestrogens can result in reproductive
problems later in life (Toppari et al,
1996).
For the
adult males, direct toxic effects on
sperm production by chemicals such as
phthalates could also be an issue.
However as far as oestrogenic effects go,
it is clear that the final 3 months of
pregnancy and the first few months of
life will be where any exposure of a male
to oestrogens is likely to have the
greatest effect. The research showing
that metabolites of DDT can block the
male hormonal system is worrying. [7]
|
Solutions
As
demonstrated by the case of the hormone polluting
shampoo, there are often simple steps that the
public can take to prevent or at least mitigate
the harmful effects. The primary obstacle though
is public awareness, people can't act or
adequately protect themselves if they don't know
or understand what they are dealing with. Sex-hormone
pollution and endocrine disrupters is an issue in
desperate need of wider public awareness; this is
the first step.
The second
step is to try and identify what's causing the
problem as this research report has already made
significant efforts to explain. The third step is
to minimize and eventually eliminate the
pollution. Researchers in Northern Ireland have
already started doing this using photocatalysis
to remove these trace chemicals from the water
supply. This process involves ultraviolet light
and titanium dioxide to neutralize the EDC or sex-hormones
in drinking water. But it should be obvious that
this doesn't stop the pollution production, it
just cleans up the municipal drinking water
supply. Also as mentioned earlier in Britain some
of the water pipes have been coated on the inside
with an EDC which would seem to negate
much of the benefits of purifying the drinking
water if it will only pick up these chemicals
between the purification plant and the consumer's
tap!
I
call for a ban on using nonylphenol ethoxylates (NPEO)
in detergent manufacturing because their
metabolites, confirmed as endocrine disrupters,
will effect humans through the food chain,"
Ding said.
The use of NPEO as nonionic surfactants, or
chemical agents that agitate surfaces, in laundry
detergents was banned by the Swiss Ordinance for
Environmental Pollutants in 1986, after
nonylphenol polyethoxylates and major metabolic
products were intensively investigated in sewage
effluent, sewage sludge and in ambient waters in
Switzerland. [9]
Clearly a
step in the right direction is to stop using and
producing known EDCs, or at least the most
pernicious ones. In many cases these chemicals
are already banned in industrialized countries
but not elsewhere. In other cases there's simply
so many chemicals being used and dumped into the
environment that identifying culprits is a very
difficult task and even then any single chemical
alone may not be a problem but taken together
they can be damaging animal, human or
environmental health. Sorting all of this out
will take time, money and significant research
but it can and should be done. The sooner the
better because only when the chemical culprits
are identified can legislative and community
action be taken to rectify sex-hormone pollution.
Further
Questions
-
Why
should we worry about lowered sperm count
when there's more than enough already?
After all it only takes one sperm to
get the job done.
-
Beyond
the cultural challenges inherent within
abnormal puberty onset are there any
long term negative effects associated
with this? I have found no significant
evidence of it yet, other than very
tentative hypothesis on higher cancer
rates. It's an important problem to
answer, do we really need to be concerned
over this from a health standpoint or is
it merely a cultural problem?
-
"Breast
cancer in China and Japan is much lower
than in Western countries. Scientists
think this could be linked to a high-fibre,
low fat diet, and yet there is high
consumption of soya in these countries,
which produces weak EDCs." How
does this fit into the picture, could it
be that these populations on average have
less breast to go cancerous? Could it be
a genetic resistance?
-
With
so many chemicals already being used and
more being created constantly, how can
they be tracked, how can they all be
tested for hormone pollution effects? And
who pays for the consequences, who will
foot the bill for water purification and
environmental cleanup of sex-hormone
pollution? Can you say - [your name here]
the taxpayer?
More
research is definitely needed to pin down the
exact chemical culprits and get a more accurate
picture of what's really going on. A serious
hindrance to full understanding of the issue of
sex-hormone pollution is the fact that although
numerous studies have and are being conducted
very little if any of it is being connected
together to form a holistic picture.
Responsibility and legal action are also notably
absent. Who is going to clean up the mess? Who's
going to pay the medical bills and who will force
the companies producing these chemical, be they
for cosmetics or detergents or whatever, from
making more and force them to switch to safer
alternatives?
In the
meantime these pernicious chemical are having a
direct and destructive effect upon human health
and the environment. Sex-hormone pollution is a
serious issue that is slowly gaining the
attention it deserves in scientific and policy
making communities but significant research and
environmental protection measures need to be
taken in the short term.
Valid strategic
solutions truly require a substantive shift in
thought, values and general philosophy, away from
simply creating a substance to generates a
specific intentional effect and leaving the
unstudied repercussions for the lawyers and the
dead fish to deal with. The move has to be made
towards actually including the consequences within the
original equation.
Indeed this
is a new form of pollution it's not intentional
but it's as dangerous and persistent as many
intentional pollution problems nonetheless. Sex-hormone
pollution is not as clear-cut as just tossing old
transformers into a pit and burying them to leach
out PCBs or tossing old computer parts into a
pile where the seep heavy metals into the water
supply. This form of pollution is direct product
of poor planning, and values that place immediate
effect above long-term consequences. It must
finally be realized that no chemical miracle
exists, every drug merely trades one symptom for
another and every chemical effect has a counter-effect
somewhere and at sometime. These consequence have
to be factored into the chemical production
equation and also accounted for both in economic
terms as well as human and environmental health
costs. 2002
The influx of
environmental hormones into our bodies happens mostly through
our food. Dioxin, nonylphenol, bisphenol A, endosulfan and other
environmental hormones are found in seafood, meat and
vegetables, and the reason they are there is because of food
containers. Plastic has been mentioned as a probable cause for
many years. Environmental hormones like diethylhexyl phthalate (DEHP)
and di(2-ethylhexyl) adipate (DEHA) are added to plastic to make
it soft, and they flow into the food from various containers.
This theory was supported by the results of a study of
environmental hormones in bottled water released by the Ministry
of Environment on Thursday. Analysis was conducted on 582
domestic and imported bottled water products last year. DEHP was
detected in 146 products, or 25.1 percent, and DEHA was detected
in 149 products, or 25.6 percent. "It is very possible that
environmental hormones contained in plastic bottles and caps
were absorbed into the water," a government official said. ...
The number of chemicals that are
classified as environmental hormones by the World Health
Organization and the U.S. Environmental Protection Agency is
between 67 to 143. The one that international researchers are
most worried about is polybrominated diphenyl ether (PBDE). It
is contained in many products that are made of plastic or fiber,
such as the casings of televisions, computers and other
household appliances, and carpets. PBDE is added to products to
make them fire resistant, but the substance can be inhaled into
the body while using them.
Fragrances, hair spray, hair mousse, and nail polishes are also
sources of environmental hormones. Contaminants such as diethyl
phthalate (DEP) and dibutyl phthalate (DBP) from these products
flow into our bodies through our lungs or skin. According to the
Korean Women's Environmental Network on Thursday, DEP and DBP
were detected in 11 perfume and nail products out of 13. These
products should be withdrawn, the group said. From:
Dangerous Hormones Found in Water Bottles, Perfume,
Chosun Ilbo (South Korea), June 1, 2007.
News
-
Sunscreen chemicals contain endocrine disruptors,
Swissinfo, 26.06.08
-
Baby bottle plastic chemical may cause hormonal problems,
USA Today 16.10.08
-
Man-made chemicals blamed as many more girls than boys are
born in Arctic. BBC, 12.09.07
-
Conventional
tests understate chemical hazards,
BBC, 13.07.07
-
Natural oils gave young boys breasts, New Scientist,
31.01.07
-
EU passes landmark 'Reach' law to control toxic chemicals,
BBC, 13.12.06
-
Study links [endocrine disrupting] pollutants to rise in
breast cancer, Independent (UK), 18.10.06
-
Polar bear genitals shrinking due to pollution,
MSNBC 23.08.06
-
Third of male fish in rivers are changing sex, Daily
Mail (UK), 19.07.06
-
Androgens common in obese teenage girls, Reuters via
IOL, 05.06.06
-
Are our products our enemy?, USA Today 03.08.05
-
Hormones in water blamed as more men seek breast reduction,
Sunday Times (UK) 31.06.05
-
Phthalates harm male reproductive development, BBC
27.05.05
-
Pollution triggers bizarre behaviour in animals, New
Scientist, 09.04.
-
Pollutants turning a third of male fish into females
10.07.04
-
Cosmetic chemicals found in breast tumours 12.01.04
-
Study reveals chemical cocktail in every person
25.11.03
-
Gender-bending
risk to children 20.10.02
-
PCBs blamed
for sex-changed polar bears 01.10.02
References
1 ) Birth
control pill causing problems for fish: DFO
Gender-bending effects: Synthetic estrogen
absorbed by fish downstream, Tom Spears,
Ottawa Citizen January 5,
2002
2 ) Boys entering puberty earlier By
Joyce Frieden, UPI Science News, 13 September
2001
3) Friends of the
Earth
4 )
Our Stolen Future -
Early signs of puberty linked
5 )
Early puberty:
Obesity, environment suspected (AP) 08/13/200
6 ) Children's Health Article Environmental
Health Perspectives Volume 108, Number 9,
September 2000
Identification
of Phthalate Esters in the Serum of Young Puerto
Rican Girls with Premature Breast Development
7)
The Complexity
of the Body
8)
Common chemicals
can reduce male fertility By Steve Connor,
The Independent, 03 July 2002
9)
Detergents end
up in Taiwan's rivers By Chiu Yu-Tzu,
Taipei Times
10)
Make-up kit
holds hidden danger of cancer Amelia
Hill Sunday April 7, 2002
Resources
|