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Fluorine - F


Fluoride (F)Fluorine is a natural element present in the earth crust. It is the most reactive of all elements and no chemical substance is capable of freeing fluorine from any of its compounds. For this reason, fluorine does not occur free in nature and it was extremely difficult for scientists to isolate.


The first recorded use of a fluorine compound dates to around 1670 to a set of instructions for etching glass that called for Bohemian emerald (CaF2). Chemists attempted to identify the material that was capable of etching glass and George Gore was able to produce a small amount of fluorine through an electrolytic process in 1869. Unknown to Gore, fluorine gas explosively combines with hydrogen gas. That is exactly what happened in Gore's experiment when the fluorine gas that was formed on one electrode combined with the hydrogen gas that was formed on the other electrode.


Today, fluorine is still produced through the electrolysis of potassium fluoride and hydrofluoric acid as well as through the electrolysis of molten potassium acid fluoride (KHF2).


Hydrogen fluoride and to some extend also some particules containing fluoride cause environmental problems. Some plant species belonging to Liliaceae such as gladiolus, tulips,... are extremely sensitive to HF. Fruit trees do not show much effects on their leaves but there can be a dramatic negative effect on fruits (peach, plum, apple, pear,...). Grass species are less sensitive but accumulate easily fluorides in their tissues. Moreover ruminants as very sensitive to fluoride intoxication that is causing teeth mottling, osteoporosis, lameness and death.


Fortunately, fluorides are less toxic to humans and fluoride accumulation in vegetables is of minor importance.Fluoride (F)


Maximum levels for fluoride in feed
There is a European regulation for feed: Guideline 2002/32/EG of 7 May 2002 in the Journal of the European Union EG L 140/10.


The Trace Element Unit at CODA-CERVA is mainly dedicated to scientific research and services in the field of food safety, public and animal health. It provides analytical facilities for third parties by the determination of trace elements in food and animal feed.


Fluorides are determined with a semi automatic analytical device (Metrohm). Fluoride analysis of food and feed were done since the early seventies. Many studies have been carried out around brickworks, fertilizer factories, glass factories,...

Nadia Waegeneers