§ Mr. Knoxasked the Secretary of State for Social Services what is the incidence of mongol births in areas of England and Wales where fluoridation of the water supply has been in force for five years or more, compared with areas where sodium fluoride is not added.
§ Sir K. JosephNo general figures are available, but a study covering 10 years of three areas in England with fluoride levels in the water of between 0.7 and 2.0 ppm and six areas with 0.2 ppm or less revealed no evidence of any relationship between the fluoride level and the incidence of mongolism.