A report of Danish and Scottish researchers revealed the theory that some chemicals, through influence on the unborn child, can be the cause of lot of trouble later: lower sperm counts, smaller penises, more cancer of testis and prostate. The researchers think that this is the case, when the chemicals mimic the female oestrogen hormone (or block the male testosterone hormone). This is the case for some tested chemicals, in vitro (on cell cultures outside the body), but not necessarily in vivo (in the body). For these chemicals for which the hormonal behaviour in humans and/or animals has been proven, the following list gives an impression in decreasing order of proven effects in real life circumstances:
Hormonal influences of chemicals:
|Hormonal influences of chemicals|
|DES-hormone (drug):||Reproduction problems for daughters,
Birth defects for sons
|Synthetic hormones:||Prevents pregnancy|
|DDE (break-down of DDT):||Problems with fish eating birds (Great Lakes),
alligators and panthers (Florida)
|PCB's:||Prevents pregnancy of seals (Waddensea)
and other wildlife
Thyroxin in seals -15%
|PAH's:||Prevents growth of plankton and mussels|
|Natural hormones:||Breast cancer
Male fish developes female behaviour
at municipal sewers
|Octyl/nonylphenol:||Male fish developes female behaviour at
municipal sewers (at high doses)
|Natural wood substances:||Male fish has female behaviour at
sewers of paper works (or the opposite?)
|DDT:||More breast cancer (doubtful)|
|TCDD-dioxin:||Less breast cancer (anti-oestrogen)
Thyroxin in new-borns +15%
In a Flemish magazine, Greenpeace accused PVC as being a threat for masculinity, because it contains nonylphenol. In some PVC-formulations this is indeed used as a grease during extrusion. Greenpeace 'forgets' to mention that nonylphenol is/was used in practically all plastics as a grease and/or as an anti-oxidant. Greenpeace also 'forgets' to mention that the bulk use of octyl- and nonylphenol is in detergents, from which use that is going directly via sewers in rivers...
In 1995, Greenpeace started a disgusting campaign, showing a man with the penis of a child, to accuse PVC of shrivelling penises. This is shocking, scientifically nonsense and contradictory to their own words: they accuse the use of non-chlorinated plastifiers in PVC to be the cause of hormonal changes in the body and therefore the chlorinated plastic PVC should be banned! The accused materials: phthalates, are indeed used in large quantities to make soft PVC, but the possible (weak) reproductive and cancerogenic properties of some phthalates are only seen at large doses in some animals like rats, not in primates (monkeys and humans). Therefore the European Commission has classified phthalates as non-carcinogenic and non-toxic and they may be used to make soft PVC blood-bags and a lot of other medical supplies.
The latest evidence of findings on phthalates is that none of the phthalates
tested in two-generation assays pose any reproduction effect whatsoever
in rats at doses far higher than environmental levels. For humans the safety
factor is even higher, because less susceptible.
Greenpeace 'forgets' to mention that the real amount ingested from PVC is near 100 milligrams a year, while the Danish Institute of Toxicology concluded that an intake of 500 mg a day was without effect,... They also forgot to mention that phthalates are found in nature, so we probably ingest a lot more (dibutylphthalate) by eating vegetables like celery.
In 1997, Greenpeace restarted its campaign against PVC, this time by acting against soft PVC in children's toys. The same false reasoning, the same scaremongering for phantom risks, the same omitting of relevant information...
Other vegetables and fruits also contain oestrogen's, sometimes in large
quantities: carrots, wheat, rice, oats, potatoes, apples, cherries, plumes,
several vegetable oils, olives, coconuts... Female gatherers do have problems
with their menstruation, just by picking hops for beer...
Last but not least: the synthetic pyrethroids, used as non persistent pesticides, show also some oestrogenic properties. They are similar to the active substances of natural pyrethrum - an extract of an African flower - which is widely used by organic growers, myself included, but not yet tested...
An investigation of the British Environment Agency , revealed that the only important oestrogenic substances in the effluents of domestic sewage treatment were natural female hormones! For some reason, the normally inactivated female hormones leaving the body, are reactivated by the bacteria in the sewage treatment. The result on male fish (roach, rainbow trout) is the production of female proteins (vitellogenin). The effect was observed at the levels of 17-beta-oestradiol and oestrone, found in all effluents tested. Amounts of ethinyl oestradiol, a synthetic oestrogen used in the pill, in a few cases were ten times lower and in most cases undetectable. Other man-made chemicals played no role at all...
Both the USEPA and the Dutch Health Commision, after studying the available evidence, do come to the same conclusion: Besides isolated cases, there is no evidence that the environmental levels of any single man-made chemical or combination of chemicals are high enough to have a significant influence.
Registration obligatory for materials harmful to reproduction:
In fact, according to Bruce N. Ames, the most important cause of birth defects for humans is alcohol! Although it is only weakly toxic, the large amounts of alcohol consumed in our world are responsible for the largest number of birth defects, see: Nature's Chemicals and Synthetic Chemicals: Comparative Toxicology. Also the intake of high amounts of Vitamin A can give severe to fatal defects on the unborn: children can be born without brains. If vitamin A was produced by a chemical factory, it would have been on all black lists of environmentalists and governments.
After reading the Greenpeace press release, you should read the comments of the authors, Theo Colburn e.a., at their official website.
After that you should read the answer of Bruce
N. Ames at:
Ageing, Cancer, & Hormones: Our Future Has Not Been Stolen
And to be complete, read the deadly sarcasm, used by the Junkman,
to knock down the "junk" science of the Theo Colburn book at:
Our Swollen Future.
You are at level two of the Chlorophiles pages.
Created: Februari 23, 1996.
Last update: October 8, 2000.
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