Despite widespread opposition, health chiefs have voted to add fluoride to the Southampton area’s water supply in a bid to tackle tooth decay.

The decision will affect around 200,000 people, including around 1,500 residents in the Nursling and Rownhams area.

The Board of South Central Strategic Health Authority (SCSHA) voted unanimously in favour of the proposals when they met at St Mary’s Stadium on Thursday of last week.

The result was met with anger by anti-fluoride campaigners gathered at the venue.

The SCSHA will now write to Southern Water to instruct them to add fluoride to the water supply at one part per million – the current level of fluoride is 0.08 ppm.

Jim Easton, chief executive of South Central SHA said: “We recognise that water fluoridation is a contentious issue for some people, but we have welcomed the opportunity that this public consultation has given us to debate this important public health issue fully with the people of Southampton and South-west Hampshire. “The board was satisfied that, based on existing research, water fluoridation is a safe and effective way to improve dental health. It is something which has been added to the water supply in parts of the UK, including Birmingham, for many years and, despite the best public health monitoring available, no significant health problems have been identified.”

During a three-month consultation 10,200 people responded to the proposals, with nearly three-quarters opposing fluoridisation.

Romsey MP, Sandra Gidley, Liberal Democrat spokesman on public health matters, said the board had made the wrong decision and “ridden roughshod” over public opinion.

“Whilst there is a lot of research on the subject of water fluoridation, much of it, like the board’s judgement, is sub-standard,” she said.

“The cost of fluoridation will be huge. It would be far cheaper and more effective to provide toothpaste and brushes to those who can’t afford it, rather than introducing a mass medication programme.

“This decision will do little or nothing for oral health and, in the long term, will only leave a bad taste in the mouths of local people.”

Borough and county councillor, Alan Dowden, added: “Why should anybody bother to participate in consultations when this example to the public demonstrates that it was purely an exercise that the authority was obliged to carry out?

“How can anyone feel confident in the future that their views will be taken into account by this deplorable example of a so called consultation?”

John Spottiswoode, chairman of Hampshire Against Fluoridation, said his group would be looking at the possibility of making a legal challenge to the decision.