Much chlorinated chemicals have effects that can be compared with the action of hormones.

Greenpeace leaflet 'Chlorine is everywhere' (in Dutch) - summer 1994.

Eurochlor kills fertility.

Greenpeace action at Diest (Belgium) - summer 1995.



Chemicals with hormonal action

At this moment, about forty chlorinated chemicals were found with a possible action on the body, comparable with hormones. On a total of more than 10,000 chlorinated chemicals, that is not much. Nevertheless, because of the possible problems, further investigations on this topic must be done.
On the other hand, a lot of (oxygenated) hydrocarbon chemicals also have such properties. That seems not to be a reason for Greenpeace to ask for a ban on the whole petrochemical or the oxygen sector.

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
Chemical Influence
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
Tributyltin:  Idem
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%
Sources: Different sources.

The influence of chlorine in hormonal changes

As you can see in the above list, there are chlorinated and non-chlorinated, synthetic and natural chemicals which have hormonal properties. The latest exaggeration of Greenpeace says that chlorine is the cause of the decline of masculinity. The authors of the above mentioned Danish report themselves denied that firmly with an open letter to the press. So did also Prof. andrology Comhair of the University of Gent (Belgium), who said: "It is not the presence of chlorine, which gives the possible oestrogenic properties. Most of the oestrogen mimics, both in potency and quantity, do not contain chlorine at all". In fact, it seems that the presence of a phenolic group is crucial for a chemical to be an oestrogen mimic. PCB's and PAH's don't contain such a group, but are oxydised in the body (just like benzene is) to phenolic type materials.

Chlorinated hormone mimics

Chlorinated products, like DDT and PCB's, that had a negative influence on reproduction are already banned for many years. And dioxins, not a chlorine chemistry problem anymore, with other possible effects, are being reduced to a minimum. See also: Toxicity of dioxins and Sources of dioxins.
Although it is possible that - in part - the influence still can be seen, it is obvious that the ban is working: DDT and DDE residues in fish of the Great Lakes are reduced already with 90% and fish eating birds are recovering yet. For PCB's in the Wadden Sea (The Netherlands), seals are recovering now too, also thanks to the seal sanctuary there. For dioxins, recent figures give a reduction to halve in mother's milk in recent years in Western European Countries (which had - and still have - the highest levels).

PVC and hormonal changes

One of the main targets of the anti-chlorine campaign of Greenpeace is PVC. In so far that Greenpeace blocks trains with VCM, the building block of PVC, using banners with 'Eurochlor kills fertility'. Eurochlor is the organisation of employers in the chlorine industry of Europe. What has PVC and VCM to do with fertility? Simply nothing.
PVC is so versatile that it has thousands of applications. That means that a lot of additives are used to make it suitable for a certain application. That is also the case for paper. PVC and paper use both about 800 different additives. This is in general no problem, neither for paper, nor for PVC.

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...

Natural hormones

A lot of plants give natural oestrogen mimics in our food. Soy is one of them. In fact soy milk is unsuitable as children's food, it contains too much oestrogen's, the baby can ingest the equivalent of several contraceptive pills.
At the beginning of this year, there was a lot of stance in the UK, because some traces of phthalates (even types not made in any factory!) were found in baby food. In fact this was far below any risk level, even for babies. That was confirmed by British and European Commission scientists. But at the same time, nobody makes a stance against the use of soy in baby food, which contains a 200 times higher amount of very potent oestrogen-like chemicals like genistein.

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 [35], 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.

Other effects on reproduction

Some chemicals can have an effect on the reproduction system itself and/or the unborn child, with or without direct action on the hormone systems. The Dutch Ministry of Social Affairs and Employment gives lists of chemicals with effects on reproduction, which are subject to registration if they are produced or used in a factory:

Registration obligatory for materials harmful to reproduction:


Source: Dutch Ministry of Social Affairs and Employment.

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.



There is still a lot of research work to do to find out if there is a real decline in masculinity and if so, what the causes are and if it is the result of pollution, which chemicals are responsible. Until now some chlorinated and non-chlorinated, industrial and especially natural materials and our very fast changed habits in food and behaviour, can be possible culprits. Because the amount and strength of the natural hormone mimics in our diet far outweighs (probably by millions of times) any possible effect of the industrial chemicals we ingest with our food, there is no evidence that whatever industrial chemical should be banned. To ask for a ban of all chlorinated chemicals, because of the large use in the past of a few possible oestrogen's between them, has nothing to do with sound science. There are as much arguments to ban all industrial activities and all natural processes and not to be forgotten: all Chinese restaurants (soy!) or to eliminate or at least reduce the female halve of the world population to save the male halve...


There is no reason to treat industrial chlorinated hormone mimics different from non-chlorinated, industrial or natural. And there is no reason at all to accuse chlorine in general or PVC in particular to be the origin of the probable sunset of masculinity in the environment.



If you want to see, how Greenpeace manipulates information, you should read the press release of Greenpeace USA asking for a ban on PVC, at the release of the book 'Our Stolen Future', by Dr. Theo Colburn, ea., this can be found under 3-14 action now against toxic hormones dioxin and PVC's .

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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