Fluoridation of Whanganui's water is a topic for debate again.
On Friday, American professor Paul Connett will present a talk about the dangers of adding fluoride to the water supply.
Author of the book The Case Against Fluoride, he has given more than 2000 lectures in 52 countries and was invited to New Zealand for a nationwide speaking tour by Fluoride Free NZ.
In the lead-up to Professor Connett's visit, local activist Lucy McDougall has been lobbying for support on what she describes as "the biggest health issue of all time".
"It's all quite scary and horrible that people aren't aware of the damage fluoride can cause.
"Professor Connett's talk is an opportunity for our community to hear exactly what risks fluoride poses on our health and environment."
For more than 60 years New Zealand has been debating the oral health effects of adding fluoride to water.
The Ministry of Health says fluoride is a natural substance that helps protect teeth by making them stronger and reducing tooth decay.
Of the 67 district councils in New Zealand, 23 have fluoridated water supplies; Whanganui does not.
In November 2016, a law was introduced to give district health boards (DHBs) the power to decide on fluoride in drinking water supplies.
This means DHBs would not have to consult the public and would be required to follow the directive of the Minister of Health, via the Crown Entities Act.
Like National, the Labour-led Government has plans to see fluoridation extended via the Health (Fluoridation of Drinking Water) Amendment Bill.
The Whanganui District Health Board has yet to make a public stance on fluoridating Whanganui's water supply.
Health board chief executive Russell Simpson said board members had not discussed fluoride and, until they did, he was unable to comment.
Mrs McDougall said that last year she gathered 700 signatures in Whanganui against fluoridated water, and she had written to all MPs.
"Everybody should have a choice over what goes into their body," she said. "When a town is fluoridated, it becomes inescapable, not only to our bodies but to our environment — no more organic gardening."
She said of the fluoride ingested only half is excreted — "the other 50 per cent accumulates in our arteries, bones and organs."
Mrs McDougall said studies showed fluoride carried major health risks, particularly for infants, children and elderly.
"It's a contributing factor in ADHD, dementia, osteoporosis, arthritis, bone cancer, and — despite what we are told by health professionals — it damages the teeth."
Professor Connett is a Cambridge graduate and has a PhD in chemistry.
His talk is at the Davis Lecture Theatre from 7pm to 9pm tomorrow and is open to the public
Dentist believes in benefits of fluoride
Whanganui dental surgeon and local councillor Hadleigh Reid supports fluoridation as a means of combating tooth decay.
But he will attend Professor Paul Connett's talk in Whanganui tomorrow because he acknowledges some people are genuinely concerned about any adverse health effects of fluoride.
Mr Reid said claims that water fluoridation could lead to cancer, bone fractures and other serious conditions were not supported by evidence.
"Often the evidence quoted by opponents has been derived from studies where the levels of naturally occurring fluoride are so high and need to be reduced, such as some parts of China and the United States."
Mr Reid said fluoride was toxic in high concentrations, a bit like chloride, but in very low concentrations both were safe and beneficial.
"At an observational level, I see a significant increase of dental decay in patients who choose to switch to a non-fluoride toothpaste."
His position on community water fluoridation is the same as the Ministry of Health's — that it makes teeth stronger and healthier.
"Water fluoridation (0.7-1 parts per million) poses no health risks, and that there is
compelling evidence of dental health benefits for all New Zealanders."