its less common in the UK nowadays – I expect the EU monitoring régime and advances in science mean most areas realise there is enough in the water already to provide some health benefits. I remember it being a controversial issue when I was in junior school!
TBH most of the scares about the stuff today seem to come from America, where health and safety is always secondary to free market considerations…
these are the results for my area..
We do not add fluoride to the water in this supply zone. There is a low level of naturally occurring fluoride. The average fluoride concentration for this supply zone from January 2010 to June 2010 was 0.447 mg/l (regulatory standard = 1.5 mg/l)