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Fluorides - total as F

including fluorine

SPRI Emission Reporting Threshold
2,000 Kg/yr Pollutant Emissions to Land
2,000 Kg/yr Pollutant Emissions to Water
2,000 Kg/yr Pollutant Emissions to Waste Water
This sheet is a generic summary, designed to give the reader a basic level of background information about the substance in question. Great care has been taken to represent as effectively and correctly as possible the broad range of (not necessarily consistent) information which is available from a variety of sources. The reader must accept therefore that this sheet has no legal status and cannot be relied upon in any legal proceedings. SEPA disclaims any responsibility or liability whatsoever for errors and omissions in this sheet.
What is it?
Fluorine is a reactive gas which is usually found in combination with metals or hydrogen in the form of fluoride salts. The properties of these salts vary. For example: sodium and calcium fluorides are both white solids, but while the former dissolves easily in water the latter does not; hydrogen fluoride is a colourless gas which readily dissoves in water to form the extremely corrosive hydrofluoric acid.
What is it used for?
Hydrogen fluoride is used in the synthesis of a variety of chemicals, for the refining of uranium to be used as a nuclear fuel and in metal processing. Hydrofluoric acid is used for ceramic and glass etching and in the manufacture of light bulbs. Sodium fluoride is added to drinking water to prevent tooth decay and is used as a preservative in glues, in glass and enamel production, in metal processing, as an insecticide and as a wood preservative. More generally, fluorides are also used as additives in dental products to prevent decay, as lubricants, in dyes, plastics and ceramic production and in some other medical applications (such as drugs to treat cancer).
Where does it come from?
The majority of fluorides in the environment are released from man's activities: coal combustion, industrial processes (particularly from the chemical and metal processing sectors) and from their application as pesticides and as additives in drinking water. Fluorides are also released naturally from the earth's crust, from volcanoes and from sea spray.
How might it affect the environment?
Fluoride compounds are found naturally at low levels throughout the environment and this does not harm wildlife or plants. However, where higher levels are found due to releases from man's activities, fluorides can be toxic. They can accumulate in both terrestrial and aquatic organisms and concentrate through the food chain. Fluorides are not thought to pose significant risks to the environment at a global level.
How might exposure to it affect human health?
Exposure to low levels of fluorides from natural sources are unlikely to harm health. Indeed, low levels are intentionally added to drinking waters to prevent dental decay. Exposure to high levels of fluorides is rare - and usually only occurs as a result of accidental spillage or in occupational settings. In some cases, even low level exposure to fluorine gas or hydrogen fluoride can cause irritation to the eyes, skin and lungs. High levels can harm the heart, lungs and even cause death. Long-term exposure to excessive amounts of fluorides has occurred in some developing countries and has resulted in widespread bone and skeletal damage. Contact with the highly corrosive hydrofluoric acid will cause severe burns.
What steps are being taken to limit the potential impacts?
The UK (including Scottish) legislation controlling releases of fluorides are the Pollution Prevention and Control (PPC) regulations. European Directives controlling emissions of fluorides include those concerned with the treatment of hazardous wastes (91/689/EEC); and pollution of aquatic environments (76/464/EEC).