TONY KELLY and M Watson (HAS, May 4) present opposing views on the desirability of adding fluorine compounds to Darlington’s water.

In many ways I believe that they are both wrong having largely missed the point. Mr Kelly mentions iodisation of table salt and the MMR immunisation process. Both processes can be avoided if you wish so leaving the choice to the consumer, however ill-advised they may be.

Similarly, chlorine in water can be removed by boiling or avoided by drinking bottled water. Chlorine at the point of use confers no known benefit, it sterilises the water in storage or in the pipes so remove it if you wish. Iodine is an essential element but if you get enough elsewhere then buy sea salt which should contain none.

The problem with fluoridisation of drinking water is that people have no option, it may well be that it’s beneficial to the majority of people, if so then I’d prefer it to be available in the same way as vitamin tablets.

That way, medical advice can be followed. The various studies, a few of which are quoted by Watson, are not, to my eye, conclusive. For these reasons I think that adding medication to everyone’s drinking water is a bad idea, after all we have all seen medical “facts” debunked after a few years when the damage is done.

As Kelly probably knows, the MMR debate is a completely different discussion. It’s well known, ask any GP, that the vaccination doesn’t ‘take’ in about ten per cent of injections and children under 12 months haven’t yet been offered it. These vulnerable people rely on “herd immunity” where most of the population are immune so the diseases don’t have a chance to propagate.

If the immunised herd isn’t a high enough percentage then the disease can be passed on. The medical belief is that this is a major reason why measles is rising in this country. The parents refusing the jab may be condemning others to this unpleasant disease. Iodine and fluorine decisions are unlikely to affect anyone else.

Anthony J. Foster, Peterlee