In the meantime we know that all chlorinated chemicals are very harmful for mankind and environment.

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




There are no toxic materials, there are only toxic doses.

Source: Paracelsus, one of the pioneers of toxicological science, about 400 years ago.

How much is toxic?

Paracelsus was and still is right. Anything can be a deadly poison, if you eat or drink or inhale too much of it. Nevertheless, there are enormous differences in amounts. When you drink about fifteen liters of water, you will not survive it. At the other side of the scale, only two billionst of a gram of botulin toxine from the botulin bacteria is enough to kill you.
Chlorinated chemicals are all between those limits. For instance from PVC-powder you can eat kilograms, it is not toxic at that dose, it will not be digested at all and will leave the body as is. Hydrochloric acid, an indispensable part of our digesting system, will only be deadly at high concentrations. Chlorine is an average poison, and TCDD-dioxin is the most powerful poison, mankind has ever made (but not voluntary).

Toxic substances in industry
All measurements in ppm (parts per million)

deadly dose which kills 50% of rats
within one hour by inhalation:
hydrochloric acid: 3124
chlorine: 293
methyl isocyanate (Bhopal): 5
ozone: 4.8
TCDD-dioxin equivalent to: 0.25
Source: List of toxic substances, Ministery of Labour, The Netherlands.

As you can see, the cause of the Bhopal disaster was the escape of methyl isocyanate (an organic nitrogen compound) from a tank. Greenpeace uses this fatal accident to say that this can happen with chlorine or hydrochloric acid too. In fact nothing is impossible, but because chlorine is sixty times less toxic, with the same circumstances, you will have sixty times less victims. And with hydrochloric acid, that would give six hundred times less victims.

Toxics in nature

If you think that nature is sweet and harmless, next figures will learn you that mankind is only a potter in making poisons, compared with nature:

Toxic substances in nature:
deadly dose which kills 50% of rats within one hour by ingestion,
all measurements in µg/kg bodyweight

deadly dose which kills 50% of rats
within one hour by ingestion:
strychnin (plant): 500
dioxin TCDD (woodfires, composting): 300
Tetradoxin (plant): 15
Tetanos toxin (bacteria): 0.0001
Botulin toxin (bacteria): 0.00003
Source: H. Compaan, Institut de Recherche TNO, Hollande.

One µg/kg bodyweight means that a microgram - one millionst of a gram - for each kg of bodyweight is enough to kill 50% of the rats within one hour. So you can see that botuline toxin is a ten million times stronger poison than the most toxic dioxin, wether it is made by nature or mankind.



Every material is toxic. Crude oil itself is toxic, so all from oil derived materials or the use of energy, uses toxic products. The same is true for almost any industry.
All industrial activities give more-or-less toxic waste. This is true for chlorine factories and for factories which don't use chlorine, for industrial and for 'natural' products. If that waste is treated accordingly, then it is no problem in either case.


There is no reason to treat the toxicity of chlorinated chemicals different from non-chlorinated. And there is no reason at all to accuse chlorine in general to give more toxic (by)products than other elements. In fact nature is a much stronger supplier of extremely toxic products than industry.


You are at level two of the Chlorophiles pages.

Created: March 10, 1996.
Last update: May 2, 1998.

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