Fluoride (F-) Posted on 11th November 201531st August 2020 by ThePD (The Project Definition) Fluoride (F-) is a chemical substance that is naturally present in many drinking water sources and is said to prevent levels of tooth decay. Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window) Related Posted in Substance and tagged chemical, health. ThePD (The Project Definition) ThePD has been developing the Preferred Project Definitions based on the actual project execution and operation experiences and knowledge with the Project Language, and sharing with you daily basis.