Recently I discussed the fluoridation issue with a self-diagnosed sufferer from fluoride sensitivity. He claimed to have irritable bowel syndrome (IBS) brought on by fluoride in drinking water. His doctor didn’t believe him but he knew better – every time he left his hometown (which is unfluoridated) for fluoridated areas his IBS returned. He assured me that the water in his city is “fluoride-free.”
I checked the published data for his city and found the natural levels of fluoride in the tap water is 0.4 ppm – not too much less than the recommended 0.7 ppm where community water fluoridation is used. He didn’t respond to my comment passing on this information – maybe it brought on an attack of IBS as stress is one of the known factors causing this.
This issue came up again at a recent Auckland City Council meeting which considered a request for fluoridation of the Onehunga water supply. Unlike most of Auckland Onehunga’s water is pumped from the Onehunga springs and is not fluoridated. In fact, a referendum in 2001 voted against a proposal to fluoridate.
But what struck me is the argument presented by one councillor that some resident of Onehunga moved there because the water is “fluoride-free” and it would violate their rights if the water supply is now fluoridated. That seems a very poor argument as anyone with a hangup about fluoride can buy and use a cheap water filter – far cheaper than shifting house. But the claim that Onehunga’s water is “fluoride-free” motivated me to check out the published data for fluoride in the Onehunga water.
So, Onehunga water is not “fluoride-free.” The average concentration is about 0.2 ppm (not too unusual for ground-water sources in New Zealand) but the actual concentrations can vary a lot. Customers would have occasionally been drinking water with a concentration as high as 0.9 or 1.1 ppm F during that time period.
Surely this would occasionally send any fluoride sensitive person into a bout of IBS, skin rash, or one of the myriads of other symptoms propagandists against community water fluoridation claim. Or perhaps only if they had been told about the high concentrations (see Fluoride sensitivity – all in the mind?).
Fluorine is the 13th most common element in the earth’s crust so it is inevitable that our food and drink contain traces derived from natural sources. In the real world, there is no such thing as “fluoride-free.”
Note: I don’t know if such variation is common with underground freshwater sources. The Onehunga aquifer derives from rainwater soaking through lava flows around One Tree Hill. It could well be prone influences from historical industrial or other sources in the locality. Apparently it has high nitrogen levels and may also be influenced by broken sewer pipes.
- Auckland Water Quality Report 2010
Auckland Water Quality Report 2011-2012
Auckland Water Quality Report 2013
Auckland Water Quality Report 2014