THE battle for our tap water is looming. New figures show south Manchester has one of the country's worst records for tooth decay, leading to fresh calls for fluoride to be added to water supplies.

Supporters of fluoridation say that areas where it has been introduced have seen massive improvements in dental health - particularly for children.

But opponents have likened the process to mass-medication and say not enough is known of the health risks.

The debate over fluoride has been reopened after the government recently gave health authorities new powers to add fluoride to tap water.

And with dental health in the North West among the worst in the country, many observers believe that Greater Manchester could be the first place to introduce fluoride since the new legislation was introduced.

Water companies in the region have already been asked to look into the costs.

And if NHS primary care trusts agree to the price, a consultation into fluoridation could begin next year and fluoride added to tap water as soon as 2008.

Ian Rhodes, spokesman for NHS North West - formerly the Greater Manchester Strategic Health Authority - said: "There's been a lot of support for fluoridation for many years in the North West because if you look at comparable areas, like Sandwell in Birmingham which already has fluoridation, there's five-times less tooth decay in children because they have had fluoridated water for many years.

"There are no proven health risks."

In a league table of the 311 health authorities in Britain, Central Manchester NHS Primary Care Trust, which oversees practices in parts of Fallowfield and Chorlton, as well as Whalley Range and Levenshulme, was ranked the 13th worst for dental health.

And South Manchester PCT, which covers Fallowfield, Withington, Didsbury, Chorlton Park, Burnage and Northenden, was 59th worst.

In these areas, the average five-year-old child has between two and three fillings or missing teeth.

In the South Manchester PCT area, less than 50 per cent of five-year-olds are free of any tooth decay and this figure falls to around a third in the central Manchester area.

The local situation compares starkly to Sandwell in the West Midlands, where water was fluoridated in the 1980s.

From having one of the worst records for childhood decay in 1985, Sandwell now has one of the best, with five-year-olds having an average of one decayed tooth.

However, opponents of fluoridation remain as vociferous as ever. Cancer, osteoporosis and even low childhood IQ have all been attributed to the process, although no conclusive evidence is available.

Withington MP John Leech said that, after weighing-up both sides of the argument, he is throwing his weight behind fluoridation.

He added: "I support adding fluoride but I also accept that a lot of people are against the idea.

"I think it is a good idea for the health of teeth and, certainly, when I speak to dentists they tell me that they are in favour of it.

"There needs to extensive consultation before it is introduced to water supplies.

"Manchester has a poor health record and I am sure that fluoride could help to address the dental side of things."