HERE we go again.

The debate about adding fluoride to the water supply is about to receive another airing.

Our letters postbag is set for another bashing now that the Greater Manchester Health Authority has announced that it wants to make fluoridation of the North-west's tap water a priority.

It is convinced that mass medication is the only way to achieve a 50 per cent reduction in tooth decay among the under-fives.

Organisations like Bolton's dental committee agree entirely, but this view has been contested vigorously in Bolton for more than 30 years and you can bet that the anti-campaigners will be active once more.

The regional health authority is looking forward to the results of a medical research study due to be published in three months' time.

If it recommends that further research is required, the region will be put forward for a pilot programme.

Should this be suggested Bolton -- which voted against fluoridation in a 1968 referendum -- can be expected to resist the idea strongly.

Bolton Council is part of the North West Councils Against Fluoride body and supports the view that there is a great deal of evidence to suggest that fluoride can be damaging to health.

This newspaper, over the years, has been against compulsory medication and sees no reason to change its mind at this stage.

It looks as though the medical establishment is embarking on new efforts to convince us that the experts know best.

But even if it wins the argument -- and there are plenty who say it will not -- the obstacles to mass fluoridation are pretty steep.

Bolton North-east MP David Crausby is already calling for a new referendum in Bolton and there could be a similar scenario in some of the other North-west towns which could be affected.

But the biggest problem blocking the way for the fluoride lobby is the fact that a privatised water company, United Utilities, would be responsible for adding the chemical.

It clearly has to look after the interests of its shareholders and will take some convincing that implementation costs -- and possible compensation claims -- are worth the risk.