Fluoridation campaigners believe they have won the argument, but the detail remains to be resolved. Mark Crail reports

In Glasgow, one child in five will have had at least one baby tooth removed by their fifth birthday. In Birmingham and Newcastle, the figure is one in 20. The difference is that Glasgow's water is not fluoridated.

Even so, water fluoridation has not proved an easy subject for the government. A late draft of the public health green paper leaked to HSJ last year simply had a blank space where the policy should have been, and there were rumours of ministerial rifts.

In the wake of the Saving Lives white paper, pro-fluoridation campaigners are hoping for rapid progress - and even legislation within the lifetime of the present parliament (see box).

They believe a study by York University's centre for reviews and dissemination will confirm that the process is safe and effective, and say that, despite pockets of resistance among local authorities - especially in the North West - oppositionist councils will not be able to derail the process.

'I know people are anxious to move forward immediately, and I feel like that myself sometimes, but you have to be realistic, ' says Michael Lennon, professor of dental public health at Liverpool University and chair of the British Fluoridation Society.

He says the alliance of 40 health groups which back fluoridation will be lobbying ministers in the autumn about the consultation process and about what constitutes 'strong' local support.

'But opinion polls consistently put support for fluoridation at about 70 per cent, which we would argue is very strong support indeed, ' he says.

He adds that a recent consultation exercise which led to an unsuccessful bid for fluoridation in parts of the North East involved eight health authorities and 24 councils, 21 of which supported fluoridation. The bid was thrown out at judicial review on the grounds that a water company's first priority was to its shareholders, not to public health.

But the judge, Justice Collins remarked that, 'the mover of an amendment to take away the (water companies') discretion in 1985 was Mr Frank Dobson, who I suppose now has it in his hands to decide whether to come back to the subject again'.

Water UK, the umbrella organisation for water supply companies, calls it 'a legal and political minefield'. Since 1985, the industry has blocked more than 50 HA requests because of fears that it may at some time face legal action.

While welcoming moves to break the logjam, its chief executive, Pamela Taylor, says: 'We are disappointed the government has not confirmed details about who will fund the cost of implementing possible future fluoridation schemes or the provision of full legal indemnity for water companies.'

The industry believes that HAs should shoulder the costs, as they will benefit from savings.

A study by York University's health economics consortium, however, suggests that such savings may be minimal, and argues that 'total dental costs are unlikely to be reduced due to the need for more restorative and periodontal treatment in later years'.

But fluoridation is cost-effective.

The study says that for high-risk areas, fluoridating a treatment works for 250,000 people costs 33p per person a year, while the benefits of extractions and fillings averted amounts to 50p.

Even so, some will fight fluoridation all the way. BFS estimates that around 30 per cent of MPs across all parties oppose it, while the all-party fluoridation committee aims to 'eliminate all artificially fluoridated water supply'.

And a small campaign group calling itself the National Pure Water Association regards fluoridation as an attempt to 'poison' or 'pollute' water. It advises people not to drink tea and to 'stay away from areas that fluoridate water supplies'.

National Pure Water Association www.npwa.freeserve.co.uk British Fluoridation Society www.derweb ac.uk/bfs/index.html

Free-flowing debate: safety and effectiveness

The Department of Health has commissioned York University's centre for reviews and dissemination to review the evidence on the safety and effectiveness of fluoridation.

If its report, due to land on ministers' desks in the spring, is positive, there will be a new legal obligation on water companies to fluoridate 'where there is strong local support for doing so'.

Local authorities will take responsibility for public consultation from health authorities.