Her technical group colleague, Finian McGrath, said he has concerns about fluoridation.

He said: “If in doubt, leave it out.”

Citing Holland and Germany as countries with good public health policy that do not put fluoride into the water, he said Ireland should be conscious of putting fluoride in the water.

Minister of State Alex White rejected the bill.

He said he accepts that it was put forward in good faith and he is prepared to continue to make public details of studies into fluoridation.

He said the public is entitled to have more information about fluoridation.