Ladies and Gentlemen,
I learned that you are discussing water fluoridation.
Therefore I'd like to supply you with additional information (see attachments too, please):
Years ago I worked scientifically with my late father, an independent European fluoride expert, on the efficacy of water fluoridation and I'm still following the debate.
I can assure you that the "benefits" of water fluoridation are by far overestimated, from a scientific point of view .
According to our studies: If there is a benefit, it reaches only up to about 0.3 ppm which also seems to be a reasonable limit for natural fluoride in water with respect to the side effect "dental fluorosis".
Dean's famous relation (21 cities study) is scientifically completely untenable, as demonstrated in my father's attached document "Fluoride Cancer Effectiveness" - see especially figs. 13 and 18.
There are more independent confirmations for that tremendous overestimation of the role of fluoridation in reducing caries.
One of them is the fact that in many countries more fluoride in water seems NOT to be associated with less caries at all (see our attached "WHO data...." publication), even the opposite seems to be the case.
And, there are 2 known principal effects which are heavily confounding any finding of a "benefit" but, until today, are NOT accounted for in virtually all, even very sophisticated, "scientific" studies of water fluoridation:
Changes in tooth eruption timing, e.g. a tooth eruption delay of few months, can yield purely PRETENDED "benefits" of up to about 50% because in this case less teeth have been exposed for a shorter time at the same age (published by my father already in 1969, a re version to not-significance demonstrated by Komarek et al. in 2005 after correction for this influence) and
the influence of vitamin D and sunshine which is now known to be able to reduce caries by far more than fluoride (William B Grant 2011, see end of "Results" in http://www.landesbioscience.com/journals/dermatoendocrinology/Grant2DE3-3.pdf) and which was recently found (not yet published) to have confounded also the - at a first glance very impressive - (Danish) fluoride-in-water-versus-caries statistics.
The question if under these circumstances their will remain a minor benefit from fluoride, out of the frequently alleged relatively small 25%, is still an open question for sound science. This question could remain unresolved, however, while fluoridation might have to retreat due to legal constraints. In Europe this happened both for legal and scientific reasons.
If you need further documents don't hesitate to contact me.
Rudolf Ziegelbecker, Mag.rer.nat., Dipl.-Ing., Dr.techn.