THE history of fluoridation is a tale of discovery, experimentation and controversy.
• 1805 – Experiments by Italian chemist Domenico Morichini and Frenchman Joseph Gay Lussac lead to the conclusion that in certain cases calcium fluoride seems to able to substitute for calcium phosphate in bones and teeth.
* 1840 – Under the influence of Morichini and Gay-Lussac’s work, German physician and chemist Justus von Liebig becomes the father of the phosphate fertiliser industry by recommending spraying fields with powdered bones and dilute sulfuric acid to replenish soil.
• 1909 – Dr Frederick McKay calls for an investigation of “Colorado brown stain” (now known as fluorosis) which affected the appearance of the teeth of children who, he noted, also had fewer cavities than average.
• 1931 – Researchers from the Aluminum Company of America (ALCOA) conclude the cause of the Colorado stain was a high concentration of fluoride ions in the region’s drinking water (ranging from 2ppm to 13.7ppm).
• 1954 – The first New Zealand experiment with topping up fluoride in drinking water begins in Hastings.
• 1957 – A New Zealand commission of inquiry is held into the effectiveness of fluoridation, resulting in its rapid expansion in the 1960s.
• 1967 – A Dunedin referendum rejects fluoridation but the city proceeds with dosing the water.
• 1980 – Auckland’s principal dental officer and staunch fluoridation advocate Dr John Colquhoun is sent on a world study tour by the Ministry of Health and returns to New Zealand opposed to fluoridation.
• 1999 – The trade union representing scientists working for the United States Environmental Protection Agency declares its opposition to fluoridation.
• Today – Fluoridation is recommended by the World Health Organisation and is used in 40 countries including New Zealand where 57 per cent of population drinks fluoridated water.