Here’s something to think about – What is the main source of contamination of our drinking water with arsenic?
Well, in the Waikato it is the Waikato river – the source water. Here are the figures,
The maximum safety limit for As in drinking water is set at 0.01 ppm As.
The concentration of As in the Waikato river varies from about 0.02 – 0.03 ppm As!
So the source water is already 2 or 3 times over the recommended safe level for As.
80% of this is removed during water treatment (by addition of a toxic, corrosive coagulant) – so the final water may have an As concentration of about 0.005 ppm As – about half the recommended maximum safe level.
When our water was fluoridated the fluorosilicic acid had a concentration of about 2 ppm As in the concentrated chemical (my own data but corresponds to certificates of analysis). Dilution at the recommended dosage produces a concentration of 0.0001 ppm As.
0.0001 ppm As from fluorosilicic acid and 0.005 ppm As from the source water itself!
The anti-fluoridation activists have complained about the wrong chemical – they should have complained about the H2O used as the source water.