PLANS to add fluoride to the water supply have won initial backing from seven out of 10 Greater Manchester's health trusts.

Manchester, Bury, Trafford, Oldham, Tameside, Stockport and Ashton, Leigh and Wigan primary care trusts have all asked regional health chiefs to produce a fluoridation plan to improve the dental health of thousands of children.

The other three trusts must decide if they want more details about the scheme, which could cost up to £100m, by the end of the month. The plans, with information on how to add fluoride and how much it would cost, should be revealed next spring and the PCTs will then vote for or against.

If they give the go-ahead, the regional health authority, NHS North West, will then decide whether to have a public consultation late next year.

All 24 north west PCTs will vote on the report, which outlines four possible flouridation schemes in parts of the region.

The schemes cost between £35m and £102m to set up.

The area has some of the worst dental health in the country, with thousands of children suffering from tooth decay.

Flouride supporters point out that in Birmingham, where it is added, there are far fewer problems with children's teeth.

The British Dental Association says fluoride in some supplies `could dramatically reduce levels of tooth decay and give children a decent start in life.'

Anti-fluoride campaigners say it is potentially dangerous mass medication and oppose public consultation, claiming people are being misled.

Research for the PCTs found fluoridation can increase the risk of fluorosis - staining on teeth - but found no evidence that it led to a higher chance of bone fractures or cancer.

Five-year-olds in Manchester have an average of 2.3 decayed, missing and filled teeth, compared to 1.47 across the north west and one across England.