I feel obliged to respond to Gary Kemp's emotive assertions about "the dangers of fluoride" (Letters, June 3).

Of course, fluorine is poisonous if ingested in excess. Chlorine, part of the same chemical family, is also extremely toxic. It seems logical, therefore, that Mr Kemp should campaign against "dumping" (his word) toxic fluoride into our water supply.

The fluoridation of water, in the few areas where it is practised in this country, is as carefully controlled as chlorination.

It is particularly of inestimable benefit to the dentition of young children. There continues to be a significant problem with rampant dental decay in young children.

While severe toothache is distressing to a child, primary teeth can rapidly also become abscessed, leading to more pain. If left untreated, further complications, such as septicaemia, may set in.

Our first recourse is to use antibiotics. This is not always effective and is only a stop-gap at best. It also exposes the child to the possibility of allergic reaction, which can be fatal in some cases, and compounds the problem of overuse, which can lead to the development of resistant strains of bacteria.

Ultimately, the teeth will have to be extracted. This usually requires a general anaesthetic which is not without hazard in itself - a number of child deaths have been reported during dental anaesthesia. I am not aware of any deaths resulting from the fluoridation of water.

Yes, in some cases dental fluorosis does occur. In most of these, it manifests as a few opaque white flecks in the dental enamel but at least the teeth are there and they are extremely resistant to decay.

Significant disfigurement from fluorosis is rare and is probably exacerbated by excessive ingestion of fluoride toothpaste.

We need to get this matter into perspective. The benefit of water fluoridation to the health of the nation is enormous. The "dangers" are blown out of all proportion.

Everything in life is dangerous if you choose to perceive it that way.

You can even kill yourself by drinking too much water, the very basis of life, regardless of whether it is fluoridated or unfluoridated.

-JE St Pierre BDS Lond LDS RCS Eng, Lewes