UK - Fluoride in our water

Fluoride in our water
P Maddison made this Environmental Information Regulations request to Severn Trent Plc

This request has an unknown status. We're waiting for P Maddison to read a recent response and update the status.
From: P Maddison
3 December 2015
Dear Severn Trent Plc,

I was going to ask if you put fluoride in the water supply for
Derbyshire, but I have since found out that you DO.

Source:
https://www.whatdotheyknow.com/request/f...
https://www.whatdotheyknow.com/request/f...

Which in one of your replies, you suggest the person should look up
your 'Fluoridation Map',
http://www.stwater.co.uk/upload/pdf/Fluo...

You also suggested that they make the request to Strategic Health
Authority. I have searched for them and the FOI website informs me
that they are 'defunct' and that they were 'NHS West Midlands'.
Because of this, I fail to see how the NHS has the authority to
demand fluoride is placed into the water system. If I am mistaken
and they are not the ones who demand it's inclusion into our water.

I would like to know;
Who decided that fluoride should be added to the water.

Why fluoride is added to the water, what are it's assumed benefits
as fluoride is a TOXIC substance. Please watch this video;
https://www.youtube.com/watch?v=P7BqFtyC...

When was fluoride first added to the water.

Where does the fluoride come from, is it a bi-product, if so, what
is it a bi-product of.

What level of fluoridation is in the water.
What level of fluoridation is considered safe.
What level of fluoridation is considered dangerous.
Does Severn Trent (or whomever this request is aimed at) have water
filtration systems in it's buildings and why.
I would like copies of the minutes of any meeting that was in
relation to fluoride.
Are there any plans to cease water fluoridation, if so, why and if
not, why.
How were the safe and dangerous levels of fluoridated water
discovered.
If you are not the one to ask about fluoridation then could you
please forward this request to whomever is.

Yours faithfully,

P Maddison