[Zyklonb]

Too much of any good thing can be a toxin. This goes for fouride probably more then other substances. However, it is a nessasary element for all life.
We generally can get all the fouride we need from the food we eat, but in some cases, depending on where you live, you can become deficient (just like iodine, which is now supplemented as iodized salt). The tiny amount of added fouride is not enough to be toxic in water, and just don't swallow toothpaste.
As for it making HF (aq), that wont make any differance.
CaF + H₃O⁺ + Cl^-  Ca²⁺ + 2 Cl^- + HF +H₂O. This will not happen enough to be even slightly toxic.

[Corribus]

When we were cave men we didn't need fluoridated water.

When we were cave men we didn't "need" penicillin. Are you ready to give up antibiotics?

When we were cave men, the life expectancy was probably about 30-35. I don't think "when we were cave men" is a very good argument for making any decision about your health.

This of course doesn't mean squat about whether you SHOULD use fluoride. But it does mean that this argument isn't a good reason why you SHOULD NOT use it.

Man, people sure are ticklish about fluoride in their water, though. I've never quite figured out why. Certainly there are better things to believe in government conspiracies about, right? There is almost overwhelming evidence that fluoride helps prevent cavities. Almost no serious dental professional or scientist or epidemiologist that I've seen has a contrary opinion. Anti-fluoride campaigns are widely endorsed by spurious snake-oil salesmen around the internet - which of course isn't proof that fluoride is good for you, or that's it isn't harmful, but it certainly should make you think twice about the motivations of people who are trying to convince you that fluoride is bad. The evidence to suggest fluoride is toxic at normally encountered concentrations is flimsy at best.

I'm no true expert on the primary literature, but if the CDC, WHO, ADA, Health Canada, and so on all hail water fluoridation as one of the most remarkable and effective health initiatives of the 20th century, I'm willing to jump on the bandwagon. Your alternative is believing in a massive conspiracy by virtually every dentist in the world, to say nothing of scientists, government agencies, and other health-care professionals - in which case, no amount of writing about the subject here is likely to convince you anyway.

My two cents.

[Eripiomundus]

When I said "when we were cavemen we didn't need fluoridated water", I should have been clearer. It was a sloppy description. What I meant was that, since man evolved in response to environmental conditions, and ionic fluorides in water were not amongst them (they received fluorides as compounds through food sources with negligible amounts in potable water supplies - excepting rare high concentration deposits), it seems reasonable to presume that ingestion of ionic fluoride, as opposed to fluoride compounds found in food sources, is not necessary for the maintenance of normal health (as things like calcium and iron are, for instance).

Your mention of penicillin is straying a little far from the context I think. I'm not referring to the modern advent of chemicals that can restore the health of someone seriously ill, I'm talking about evolutionarily derived daily nutritional requirements, established in response to eons of environmental pressure. Those pressures may have radically changed in the last five thousand years, but our evolved biological mechanics don't change as radically. Hence what was good nutrition for a pre-sapiens hominid is still good for us today. That is not to say that civilisation has failed to confer survival benefit. It definitely has, but the basic nutritional requirements of a human have not changed.

Your comparison of the lifespans of our ancestors to our own is a little misleading I think. The ancestors of man had myriad obstacles to overcome in order to survive. Life was hard: predation, bacterial/fungal/viral infection/infestation, exposure to weather extremes, poisons/bites/stings, dehydration/drought, flood, exposure, higher risk of physical injury due to increased quantity and quality of activity, fire, sickness, starvation... It is almost meaningless to compare lifespans unless you incorporate the contributing factors.

The rate of disease has increased concurrently with the rise of civilisation, owing to increases in population density allowing for the rapid dissemination of pathogens, so the advent of penicillin has probably had more effect on modern health than it would have in past epochs where the spread of pathogens was contained by larger distances between, and smaller groupings of, potential hosts. 

It's easy to label something a 'conspiracy theory', and thereby instantly detract from its legitimacy, but your comment that, since the CDC, WHO, ADA... hail fluoridation as a miracle health initiative you are willing to jump on the bandwagon, strikes me as exactly the type of mob mentality your post denounces. You basically say: X an Y say fluoride is ok. I think they're credible, I'm with them. You haven't taken the time to research it for yourself, yet feel vindicated in extolling an authoritative pronouncement. This is the same force that gathers momentum to a conspiracy theory.

I've read reports from both sides, and there are, contrary to what you seem to believe, very provocative arguments against fluoridation from well respected organisations (Harvard university, for instance). You mention that there is 'overwhelming evidence' providing for the beneficial role of fluoride in dental maintenance, but I've looked (previously), and these are very limited studies in scope. The only beneficial evidence relates to topical administration, and even these findings are relatively weak. Look into the dental benefits of increased intakes of vitamins A, D and K, and you will find results for dental maintenance that overshadow those of fluoride by a significant margin. Almost all governmental information pertaining to health benefits of fluoride are simple varnish. They contain no substance, no hard evidence, and even fall short of what I would label 'pop-science'.

Every piece of what I would call thorough research on the topic says that topical administration has dental benefit while ingested fluoride has none, plays no biological role and, given its bio-accumulative nature, poses a risk to health under sustained daily exposure. 

I'm not saying I believe fluoride to be the monster some claim it is, but the sheer bulk of concern provoked me to look into, and I have to say that there seems a compelling argument there.

Thanks for your comments though.