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What is chlorine

Dear Reader,

After the recent event in Kansas, some of my readers might want to know what chlorine is. Well chlorine is one of the elements of the periodic table, it is a green / yellow corrosive gas but like many things the form of it controls how good / bad it is for you.

In the form of the element it is toxic to all lifeforms, but in the form of common salt (table salt) which has the chemical name “Sodium Chloride” it is a vital substance required by people in their food (in moderation) and for many household and industrial processes.

Before you get too concerned by the fact that chlorine is toxic to all forms of life, consider for a moment how you would rather not have live germs in your drinking water, a small amount of chlorine added to drinking water will kill the nasty germs. The small amount of chlorine in the tap water is not dangerous to people but please take care when you add water to your fish tank to treat it with a chlorine neutralizer. For many substances a human, plant or animal can tolerate a small amount each day. For example if I was to drink a tea spoon of gin each lunch time then it would have no adverse effect on my health. even if I continued in this habit for the whole of my life. On the otherhand if I saved all my lunch time gin up for several years and then drink it in one afternoon then I would be a very bad way.

I know in the past some people have regarded chlorine as the devil’s element, I think that this is rather silly and unscientific. <Sarcasm>Anyway I thought that the devil’s element was sulfur </Sarcasm>. But seriously if anyone tells you that chlorine is the devils element and must be banned you should reject this statement, I always used to say I will take that idea with a pinch of salt.

Chlorine is needed for a wide range of industrial and household products but sadly in recent years it seems to have become a bug bear for the environmental movement. For example Greenpeace have wasted a lot of effort and time going on and one about the evils of PVC. They seem to hate the stuff. You might be interested to know that some of their horror stories about PVC and chlorine chemicals have been debunked by the chlorophiles.

I hold the view that PVC is a very useful plastic, it is very good and safe in many applications and normally it is some of the additives which are the real problem.

For example PVC water pipes and uPVC window frames are perfectly safe, but on the other hand I would not want to store a fatty food in a container made from some grades of soft PVC. This is because I would rather not ingest some of the additives such as some of the pthalates in my food.

It is interesting that in recent times people have become scared of plastic food containers, for example on Mumsnet there is a recent thread about this topic. Now I would say we need to be careful about “all vs some“. While some grades of plastic are not safe for food containers, for example I would never buy a olive oil processing machine in which the oil was heated in an ABS container which contained small molecule flame retardants, I would be perfectly happy with a olive oil machine which used polypropylene instead. This is becuase polypropylene is a polymer which is normally free of the hazardous additives.

Other plastics which should be very food safe will include polyethyene, PET and polylactic acid.


One Response

  1. This is a really informative post. Chlorine toxicity is something I have always been concerned about, but you did a great job explaining the differences in compounds to a novice like me. I’ll be sure to share this knowledge with my readers, while they browse my site for Chlorine Slogans If you have time, check it out.

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