Flouride

What is Fluoride?
Fluoride can occur naturally in some water sources however it is mostly found in drinking water due to Fluoride being added as part of the treatment process. Public water supplies in Ireland and in many other countries add fluoride, typically in the form of Hydrofluorosilicic acid (H2SiF6), to drinking water to reduce cavities in teeth. In the Drinking Water Regulations, it is defined as a Chemical parameter.
What is an exceedance for Fluoride?
The drinking water directive outlines 2 limits for the fluoride parameter: (a) in supplies where Fluoride is added the limit is 0.8 mg/l (b) in supplies with naturally occurring fluoride, not needing further fluoridation the limit is 1.5 mg/l. Therefore, any results above these levels defined by supply source or treatment type is an exceedance for Fluoride.
How would an exceedance for Fluoride occur?
Fluoride exceedances in supplies where Fluoride is not added indicates that the source has naturally-occurring high levels. However, if an exceedance occurs in a supply where Fluoride is added to the water then it suggests that an issue has occurred with the dosing system at the treatment plant.